e) xtended, 17. Which of the following mechanisms of activation is characteristic of tyrosine kinase receptor activation? a) ion conductance b) dissociation of repressor protein c) G-protein signalling d) Receptor internalization e) None of the above

Please give the answers only

Q30

The p75 receptor differs from Trk receptors in that it a) can promote cell death. b) has high affinity for all neurotrophins. c) only binds a particular type of neurotrophin. d) can bind NGF to promote cell survival.

Sort the following steps of GPCR signal propagation (you may not use all the steps): A) Dephosphorylation of GPCR B) G protein dissociation to adenylate cyclase and GTP binds to the G protein C) Ligand binding to GPCR D) G protein dissociation from GPCR and GDP binds to the G protein E) Synthesis of CAMP F) Activation of PKA G) G protein association to adenylate cyclase H) G protein dissociation from GPCR and GTP binds to the G protein O F, C, H, F, B OC OB, D, A, E, H O C, H, G, E, F OA, G, H, B, E

22. Xenobiotics Y & Z are agonists for a G-protein coupled receptor and tyrosine kinase receptor, rerspectively. When combined, cross-talk between activated signaling pathways can lead to which of the following types of interaction? a) Additive effects b) Antagonistic effects c) Synergistic effects d) b & c e) all of the above

12. Which statement regarding cell-surface receptors is correct? A) lon-channel-coupled receptors alter the membrane potential directly by changing the permeability of the plasma membrane. B) G-protein-coupled receptors are polypeptides with seven transmembrane domains. C) After binding their ligand, G-protein-coupled receptors interact with intracellular GTP-binding proteins, later initiating signal transduction events. D) All of the above E) None of the above Answer: Explanation:

Signaling by tyrosine kinase receptors is generally associated with all of the following except: OA) receptor dimerization B) growth factor responses C) heterotrimeric G proteins OD) cross phosphorylation E) generating protein binding sites due to phosphorylation

Nerve growth factor binds to which type of receptor? a.) Receptor tyrosine phosphatases b.) Receptor Serine/Threonine Kinase c.) Receptor guanylyl cyclase d.) Receptor tyrosine kinase

The transforming growth factory beta (TGF-b) family of hormones / growth factors are dimers and they interact with specific receptors. Which of the following statements about these receptors is correct?   a)   A receptor complex is formed from a type 1 and a type 2 receptor  b)   A receptor complex is formed between the ligand and the receptor  c)   This family interacts with a single serine- threonine kinase receptor  d)   The major receptor is intracellular  e)   The receptor is a G-protein receptor