For each element in the list that follows, indicate what kind of molecule it is (DNA, RNA, protein, small molecule), whether it acts as a positive or negative regulator, what stage of gene expression it affects, and whether it acts in cis or in trans . (In its most general sense, the term cis describes elements that affect the function of the molecule of which it is a part, while trans describes elements on one molecule that affect the function of a different molecule.) a. Lac repressor b. lac operator c. CRP d. CRP-binding site e. Trp repressor f. charged tRNA Trp (in terms of its function at the Trp trp operon) g. the antiterminator at the trp operon h. a terminator in the expression platform of a riboswitch i. an sRNA that blocks mRNA translation

Question

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Answer 1

Textbook Question

Chapter 15, Problem 26P

For each element in the list that follows, indicate what kind of molecule it is (DNA, RNA, protein, small molecule), whether it acts as a positive or negative regulator, what stage of gene expression it affects, and whether it acts in cis or in trans. (In its most general sense, the term cis describes elements that affect the function of the molecule of which it is a part, while trans describes elements on one molecule that affect the function of a different molecule.)

a. Lac repressor

b. lac operator

c. CRP

d. CRP-binding site

e. Trp repressor

f. charged tRNA^Trp (in terms of its function at the Trp trp operon)

g. the antiterminator at the trp operon

h. a terminator in the expression platform of a riboswitch

i. an sRNA that blocks mRNA translation

Expert Solution

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Expert Solution

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Expert Solution

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Expert Solution

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Expert Solution

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Expert Solution

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Expert Solution

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.

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Answer 2

Textbook Question

Chapter 15, Problem 26P

For each element in the list that follows, indicate what kind of molecule it is (DNA, RNA, protein, small molecule), whether it acts as a positive or negative regulator, what stage of gene expression it affects, and whether it acts in cis or in trans. (In its most general sense, the term cis describes elements that affect the function of the molecule of which it is a part, while trans describes elements on one molecule that affect the function of a different molecule.)

a. Lac repressor

b. lac operator

c. CRP

d. CRP-binding site

e. Trp repressor

f. charged tRNA^Trp (in terms of its function at the Trp trp operon)

g. the antiterminator at the trp operon

h. a terminator in the expression platform of a riboswitch

i. an sRNA that blocks mRNA translation

Expert Solution

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Expert Solution

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Expert Solution

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Expert Solution

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Expert Solution

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Expert Solution

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Expert Solution

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.

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Answer 3

Textbook Question

Chapter 15, Problem 26P

For each element in the list that follows, indicate what kind of molecule it is (DNA, RNA, protein, small molecule), whether it acts as a positive or negative regulator, what stage of gene expression it affects, and whether it acts in cis or in trans. (In its most general sense, the term cis describes elements that affect the function of the molecule of which it is a part, while trans describes elements on one molecule that affect the function of a different molecule.)

a. Lac repressor

b. lac operator

c. CRP

d. CRP-binding site

e. Trp repressor

f. charged tRNA^Trp (in terms of its function at the Trp trp operon)

g. the antiterminator at the trp operon

h. a terminator in the expression platform of a riboswitch

i. an sRNA that blocks mRNA translation

Expert Solution

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Expert Solution

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Expert Solution

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Expert Solution

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Expert Solution

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Expert Solution

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Expert Solution

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.

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Answer 4

Textbook Question

Chapter 15, Problem 26P

For each element in the list that follows, indicate what kind of molecule it is (DNA, RNA, protein, small molecule), whether it acts as a positive or negative regulator, what stage of gene expression it affects, and whether it acts in cis or in trans. (In its most general sense, the term cis describes elements that affect the function of the molecule of which it is a part, while trans describes elements on one molecule that affect the function of a different molecule.)

a. Lac repressor

b. lac operator

c. CRP

d. CRP-binding site

e. Trp repressor

f. charged tRNA^Trp (in terms of its function at the Trp trp operon)

g. the antiterminator at the trp operon

h. a terminator in the expression platform of a riboswitch

i. an sRNA that blocks mRNA translation

Expert Solution

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Expert Solution

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Expert Solution

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Expert Solution

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Expert Solution

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Expert Solution

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Expert Solution

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.

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Answer 5

Textbook Question

Answer 6

Textbook Question

Answer 7

Expert Solution

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Expert Solution

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Expert Solution

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Expert Solution

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Expert Solution

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Expert Solution

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Expert Solution

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.

Answer 8

Expert Solution

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Answer 9

Expert Solution

Answer 10

Expert Solution

Answer 11

Expert Solution

Answer 12

Summary Introduction

a.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Lac repressor.

Introduction:

Lac repressor is involved in inhibiting the transcription of the lac operon. In unavailability of lactose, the lac repressor binds to the operator tightly and inhibits transcription.

Answer 13

Explanation of Solution

Lac repressor is a protein molecule, and it acts as a trans element. Lac repressor acts as a negative regulator of genes. The repressor protein that is synthesized by the gene i of lac operon binds to the operator to inhibit transcription. When lactose is present in high concentration in the cell, it binds to the repressor and makes it unfit for binding. In this case, the RNA polymerase transcribes the structural genes.

Answer 14

Expert Solution

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Answer 15

Expert Solution

Answer 16

Expert Solution

Answer 17

Expert Solution

Answer 18

Summary Introduction

b.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of lac operator.

Introduction:

The operator is basically a small region of DNA that is partially present within the promoter. It interacts with the regulatory protein and controls the transcription of the lac operon.

Answer 19

Explanation of Solution

The lac operator is a DNA molecule, and it acts as a cis element. It is considered to be a positive regulator. The gene O of the lac operon is the site of the operator, where the repressor protein tends to bind.

Answer 20

Expert Solution

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Answer 21

Expert Solution

Answer 22

Expert Solution

Answer 23

Expert Solution

Answer 24

Summary Introduction

c.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP.

Introduction:

CRP or cAMP Receptor Protein consists of cAMP. It is involved in binding next to the promoter region and then helps the RNA polymerase to bind to the promoter. CRP protein plays a role in upregulating the transcription of the lac operon.

Answer 25

Explanation of Solution

CRP is a protein molecule, and it acts as a trans element. It is known as the positive regulator. As the bacteria utilize glucose more as compared to the lactose, the attachment of RNA polymerase to the promoter needs the presence of CAP (catabolite gene activator protein) or CRP (cAMP receptor protein) bound to the cyclic AMP. The presence of glucose lowers the concentration of cAMP, which, as a result, lowers the formation of CAP-cAMP. As a result RNA polymerase does not bind to DNA in the presence of glucose. As a result, after the addition of glucose, the transcription of the lac operon is decreased.

Answer 26

Expert Solution

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Answer 27

Expert Solution

Answer 28

Expert Solution

Answer 29

Expert Solution

Answer 30

Summary Introduction

d.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of CRP-binding site.

Introduction:

The CRP binding site is the site present on the lac operon, where the CRP protein binds. The CRP protein is involved in upregulating the process of transcription of lac genes

Answer 31

Explanation of Solution

The CRP binding site is a type of DNA molecule, and it acts as a cis element. It is known to act as a positive regulator. The CRP-binding site is the DNA region, where the CRP binds.

Answer 32

Expert Solution

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Answer 33

Expert Solution

Answer 34

Expert Solution

Answer 35

Expert Solution

Answer 36

Summary Introduction

e.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of Trp repressor.

Introduction:

The trp repressor is a type of transcription factor that is involved in controlling the metabolism of tryptophan. When trp repressor is bound to tryptophan, the complex attaches to the operator and blocks the RNA polymerase from binding to the promoter and preventing the transcription of the operon.

Answer 37

Explanation of Solution

The trp repressor is a protein molecule, and it acts as a cis element. This protein is known to act as a negative regulator. The trp repressor is produced by trpR gene, which is present in upstream to the promoter. In the presence of tryptophan, the trpR protein binds to the operator and prevents the RNA polymerase from binding and transcribing the operon. As a result, tryptophan is not synthesized from the precursor. In the absence of tryptophan, the repressor gets unable to bind to the operator, and the transcription is continued.

Answer 38

Expert Solution

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Answer 39

Expert Solution

Answer 40

Expert Solution

Answer 41

Expert Solution

Answer 42

Summary Introduction

f.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of charged tRNA^Trp.

Introduction:

When tryptophan is present in limiting concentration, the tRNA^Trp will also be present in insufficient amount. As a result, the translation will pause at the tryptophan codon.

Answer 43

Explanation of Solution

The charged tRNA^Trp is a type of protein molecule, and it acts as a trans element. It is considered as a positive regulator. The ribosomes bind to mRNA and recruit the tRNA molecules bound with tRNA specific amino acids. This tRNA contains anticodons that are complementary to the codon sequence of mRNA.

Answer 44

Expert Solution

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Answer 45

Expert Solution

Answer 46

Expert Solution

Answer 47

Expert Solution

Answer 48

Summary Introduction

g.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of the antiterminator at the trp operon.

Introduction:

When the charged tryptophanyl tRNA is present in a deficient concentration, the ribosome that is involved in translating the leader peptide sequence stalls and the antiterminator structure forms.

Answer 49

Explanation of Solution

The antiterminator at the trp operon is a RNA molecule, and it acts as a trans element. It acts as a positive regulator. The Trp operon is known to be regulated by a process known as attenuation. The occurrence of this process is only possible in the presence of a leader sequence coding for a leader peptide. The peptide consists of two trp codons lying adjacent to each other. The attenuator RNA, which is also known as antiterminator structure, consists of four short sequences, which form three distinct secondary structures. This formation of stem-loop structure functions as an antiterminator.

Answer 50

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Answer 51

Expert Solution

Answer 52

Expert Solution

Answer 53

Expert Solution

Answer 54

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of a terminator in the expression platform of a riboswitch.

Introduction:

The riboswitches are known as the regulatory segment present in the mRNA molecule that has the tendency to bind to a small molecule. This binding results in the change in the production of proteins that are coded by mRNA.

Answer 55

Explanation of Solution

A riboswitch is a protein molecule, and it acts as a cis-element. Riboswitches act as a negative regulator. These riboswitches are located in the untranslated regions of mRNA. The metabolites that bind to riboswitches send a feedback signal to regulate the transcription of RNA or the initiation of translation.

Answer 56

Expert Solution

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.

Answer 57

Expert Solution

Answer 58

Expert Solution

Answer 59

Expert Solution

Answer 60

Summary Introduction

h.

To determine:

The type of molecule (DNA, RNA, protein, small molecule), type of regulation (Positive or negative), the stage of gene expression affected, and the mode of action (cis or trans) of an sRNA that blocks mRNA translation.

Introduction:

The sRNA are the small bacterial RNA that are 50-500 nucleotides long non-coding RNA molecules.

Answer 61

Explanation of Solution

sRNA is an RNA molecule, which acts as either cis and trans molecule depending on the target mRNA. It is considered as a negative regulator. The sRNA are known as the posttranscriptional regulators because they regulate gene expression on base pairing to target mRNAs.