Concept explainers
To review:
Three essential posttranslational steps are mentioned in figure
a. A research scientist is intent to produce human insulin in the bacterial species E. coli. Whether the genetic code permits the production of human proteins from bacterial cells? Explain with reason.
b. Describe why it is not feasible to insert the complete human insulin gene E. coli and anticipate the production of insulin.
c. Recombinant human insulin that is prepared by inserting human DNA encoding insulin into E. coli, is one the most extensively used recombinant in pharmaceutical products in the world. Recognize the part of the human insulin gene used to generate recombinant bacteria that produce human insulin.
Introduction:
Preproinsulin is the primary translational product of the Insulin gene. It is made up of
The post translational modifications include cleavage of N terminal amino acids, Chemical modification of internal amino acids, and polypeptide cleavage.
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Genetic Analysis: An Integrated Approach (3rd Edition)
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- You are given 3 tubes of RNA and asked by your supervisor to clone the gene encoding the proinsulin C-peptide that will be used later to produce insulin. The first tube contains purified mRNA isolated from pancreatic β-cells from a patient in a postabsorptive state. The second tube contains purified mRNA isolated from pancreatic α-cells from a patient during absorptive state. The third tube contains purified mRNA isolated from pancreatic β-cells from a patient during absorptive state. In not more than 2 pages (using 1.5 line space of Arial or Times New Roman fonts) provide answers for the following questions? 1) Which tube from the three is the most appropriate to use and why? 2) Describe the primary procedure (key steps no details) that you will follow to clone the Cpeptide gene from the RNA above into the only vector you have, a pUC expression vector cut open using EcoR1 which has a 5recognition site and a 3HindIII in the MCS? 3) How can you guarantee a high expression of your…arrow_forwardMature human insulin is synthesized from a single Gene but contains two polypeptide chains (A and B) linked by disulfide bonds. Which of the following statements about the A and B chains provides the best explanation for the production of human insulin? a. They are identical and combine to form the mature insulin b. They are produced by proteolytic processing of a single translation product d. c. They are the products of alternative translation-initiation sites on a single mRNA They are the product of a separate A- and B-chain mRNA produced by alternative splicing e. They are the products of separate A- and B-chain mRNA synthesized from alternative promotersarrow_forwardYou are given 3 tubes of RNA and asked by your supervisor to clone the gene encoding the proinsulin C-peptide that will be used later to produce insulin. The first tube contains purified mRNA isolated from pancreatic β-cells from a patient in a post-absorptive state. The second tube contains purified mRNA isolated from pancreatic α-cells from a patient during absorptive state. The third tube contains purified mRNA isolated from pancreatic β-cells from a patient during absorptive state. 1) Which tube from the three is the most appropriate to use and why? 2) Describe the primary procedure (key steps no details) that you will follow to clone the C-peptide gene from the RNA above into the only vector you have, a pUC expression vector cut open using EcoR1 which has a 5¢-recognition site and a 3¢- HindIII in the MCS? 3) How can you guarantee a high expression of your protein in any expression vector?arrow_forward
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning