Suppose a researcher discovers a new growth-factor signal-transduction pathway. When the researcher adds the nonhydrolyzable GTP analog GTPYS, the duration of the hormonal response increases. Why does the hormonal response last longer in the presence of GTPYS? O The Ga-GTPYS complex has higher affinity for GB and Gy than for adenylate cyclase. Ga binds covalently to adenylate cyclase in the presence of GTPYS. O The G protein in this signal-transduction pathway is defective for nucleotide binding. GTPYS prolongs the Ga-adenlylate cyclase association because GDP formation cannot occur. Adenylate cyclase binds to GTPYS independently of the G protein.

Suppose a researcher discovers a new growth-factor signal-transduction pathway. When the researcher adds the nonhydrolyzable GTP analog GTPYS, the duration of the hormonal response increases. Why does the hormonal response last longer in the presence of GTPYS? O The Ga-GTPYS complex has higher affinity for GB and Gy than for adenylate cyclase. Ga binds covalently to adenylate cyclase in the presence of GTPYS. O The G protein in this signal-transduction pathway is defective for nucleotide binding. GTPYS prolongs the Ga-adenlylate cyclase association because GDP formation cannot occur. Adenylate cyclase binds to GTPYS independently of the G protein.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 5TAHL

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