Once an activated signaling pathway has elicited the proper changes in target gene expression, the pathway must be inactivated. Otherwise, pathological consequences may result, as exemplified by persistent growth factor initiated signaling in many cancers. Many signaling pathways possess intrinsic negative feedback by which a downstream event in a pathway turns off an upstream event. Describe the negative feedback that down-regulates signals induced by (a) erythropoietin and (b) TGF-β.

Q: 1) One cell-signaling pathway implicated in the regulation of cell division is the mTOR/Akt pathway.…

A: mTOR/Akt pathway involved in cell division.

Q: Which of the following signaling pathways use conventional molecular activation cascades (signaling…

A: Signaling pathways are a series of chemical reactions within a cell that occur in response to a…

Q: Cancers are often caused by overactive growth factor receptor signaling (remember growth factor…

A: Cancer is a disease which is caused by the uncontrolled growth of the cells, without regulation of…

Q: The MARCH-1 E3-ubiquitin ligase is expressed in B cells, dendritic cells, and macrophages. The…

A: Pathogens have evolved various mechanisms to evade the host immune system. One such mechanism is to…

Q: a. A typical cellular response of a mammary epithelial cell to EGF signal is proliferation. the Kd…

A: Proliferation is the cellular response.

Q: Tumor necrosis factor alpha (TNF-α) is an important cytokine used by immune cells to initiate and…

A: We are given a receptor ligand interaction as shown below.T + R  C'T' is the ligand (TNF-), 'R' is…

Q: In this mechanim of receptor regulation, there is uncoupling of the signaling pathway. Even though…

A: Introduction   Receptor regulation is the homeostatic increase or decrease in receptor activity/…

Q: Metabolic syndrome is a clustering of various conditions including high blood pressure, high blood…

A: Metabolic syndrome is a group of disorders that occur in tandem and increase your risk of heart…

Q: a) What purpose does this forward reaction serve in that pathway?  b) Does the reverse reaction…

A: The Hippo signaling pathway is an evolutionarily conserved signaling pathway that is the latest…

Q: Use the SGF-signaling pathway image as a reference, to answer the following questions. Use the data…

A: ANSWER;-

Q: Receptor, especially growth factor receptor signaling is deregulated in cancer cells, which results…

A: Growth Factor Receptors- These growth factors in cancer cells are also known as polypeptides which…

Q: Non-canonical Hedgehog signaling results in actin cytoskeleton rearrangements, leading to cell…

A: Hedgehog is a protein present on the cell membrane which helps in the changing the cell movement and…

Q: T-cell receptor signaling leads to enhanced integrin-mediated cell adhesion.  T-Cell Receptor…

A: According to the question, a graph has been displayed which demonstrates that T cell Receptor…

Q: RAS is a signal transducer that acts as a switch for turning on cell division. Drag the descriptions…

A: Cells communicate with each other through specific chemical signaling pathways that are known as…

Q: Describe the functions of various components of intracellular signaling pathways with diagrams.…

A: The cell signaling is the process of cell communication within the body. It is the ability of cells…

Q: Explain how expression of a dominant-negative mutant of JAK blocks the erythropoietin (Epo)-cytokine…

A: Cytokine receptors include the receptor proteins for cytokines and some hormones.

Q: TSC acts as a tumor suppressor by continually suppressing mTOR and must be inhibited in order for…

A: TSC (Tuberous Sclerosis Complex) acts as a negative regulator of the mTOR (mechanistic target of…

Q: TLRs activate NFkB, AP-1, and IRF transcription factors to induce the expression of inflammatory…

A: The activation of transcription factor such as NFkB, AP-1, and IRF is a complex mechanism involving…

Q: Describe the relationship between Insulin Growth Factor (IGF) and aging.  What role does IGF play in…

A: Insulin Growth Factor IGF is also called somatomedin C. It is structurally similar to the hormone…

Q: Consider the following simplified diagram of a signal transduction pathway that regulates…

A: Apoptosis, or programmed cell death, is a tightly controlled process that is essential for the…

Q: Consider the mTOR pathway described below. Which of the following would be an example of negative…

A: The mTOR (mammalian target of rapamycin) signaling pathway is a critical cellular pathway that…

Q: Basal cell carcinoma arises from inappropriate activation of the Hedgehog pathway. Which of the…

A: Basal cell carcinoma is a type of skin cancer. Basal cell carcinoma begins in the basal cells is a…

Q: Which of the following statements regarding signaling in normal cells and cancer cells is false? a.…

A: Mutations in signaling pathways cause cancer cells to proliferate uncontrollably, defy apoptosis,…

Q: The small fragments of some complement proteins initiate a local inflammatory response.  Recent…

A: In the body, there are certain plasma proteins seen, known as complement proteins. They are…

Q: Most mammalian cells have a single immobile cilium called the primary cilium, in which…

A: Intraflagellar transport (IFT) is the process by which proteins are transported into cilia. It…

Q: Aberrant signaling through the Ras-BRaf-MAPK signal transduction pathway drives many cancers. This…

A: Ras-BRaf-MAPK signal transduction pathway is well characterized pathway and known to transduce…

Q: Practice ques tion 1A Mutations in the signalling pathways depicted above have been associated with…

A: For cancer to be triggered in any higher organism generally and mammals specifically, the need is to…

Q: How ion channels will specifically target the cancer cell and not the normal cells or the cells…

A: Apoptosis also known as organized cell death is a mechanism through which a cell, which is no longer…

Q: Briefly describe how inflammation can contribute to carcinogenesis and disease progression through…

A: Tumors are heterotypic collections of many cell types including cancer stem cells, progeny tumor…

Q: Which of the following modifications of the Epithelial Growth Factor Receptor (EGFR) would be…

A: Epidermal growth factor receptor is a transmembrane protein that spans the length of the cell…

Q: Binding of TGF-β to its receptors can elicit a variety of responses in different cell types. For…

A: TGF-1–3 are multifunctional growth factors that are exclusively found in mammals and are released…

Q: The output of RTK pathways is often the activation of MAP Kinase. Explain how MAPK can lead to…

A: There are many intercellular signaling pathways processing in the cells. RTK pathway is a…

Q: Signaling pathways often require receptor dimers to become active. What would be an advantage of the…

A: Most receptors dimerize during their association with their ligands. This dimerization provides them…

Q: TCR and CD28 signaling together leads to maximal production of IL-2 by the activated T cell.…

A: Costimulation may cause the increased production of cytokines by increasing the formation of mRNA.…

Q: Lactase can be classified as which type of enzyme? O A. Isomerase O B. Hydrolase O c. Transferase…

A: Enzymes are categorized into 6 main…

Q: hich of the following statements is true?   Question 2 options:   a)  All cells will respond to…

A: paracrine signaling is a fundamental cellular communication process that allows cells to interact…

Q: how is sustained proliferative signaling necessarry for cancer development and how is it a driving…

A: Cancer is when abnormal cells divide in an uncontrolled way.  Abnormalities are generally due to…

Q: A cell signaling molecule that triggers an effect only in the vicinity of the cell secreting is is…

A: In multicellular organisms, cells can send and receive chemical messages constantly to coordinate…

Q: Describe the effects of the over-expression of mdm2 on cell proliferation and apoptosis on cell…

A: Mouse double minute 2 homolog (MDM2) is a gene isolated from a mouse chromosome and is encodes MDM2…

Q: Vitamin A, retinoids, plays critical roles in development. Explain the molecular mechanism through…

A: Dietary vitamin A and its active metabolites are essential nutrients for many functions as well as…

Q: Give an overview of the pathway and what it does, and explain the nature of the TNF ligand and the…

A: Tumor necrosis factor-alpha (TNF) is a cytokine that affects nearly every cell type.  It causes…

Q: that binds Fsh3 is a receptor tyrosine kinase (RTK) and there are numerous fish tumor cell lines…

A: Answer. Enzyme-linked receptors are a second major type of cell surface receptors. Like…

Cell Signaling

It allows cells to perform various cellular activities, coordinate, and interact with other cells. All cells of an organism receive signals from their environments and respond accordingly. Even the unicellular eukaryotes receive signals secreted by other cells and respond. In the case of yeast, mating takes place by signaling between the yeast cells. Communication by cell signaling in a multicellular organism has become a vast and important part of various fields of biology.