MCDB 418- Midterm Exam Guide - Comprehensive Notes for the exam ( 18 pages long!)

• School: U of M
• Department: Molecular, Cellular and Developmental Biology
• Course: MCDB 418
• Professor: Cunming Duan

Document Summary

What are second messengers: criteria of second messengers. 1970s, sutherland demonstrated that hormone treatments increase production of intracellular camp. This seminal finding led to birth of 2nd messenger theory. Sutherland suggested the following criteria for second messengers: The mediator or its analog must mimic the action of the hormone. The levels of mediator should be altered by the hormone. There should be an appropriate temporal relationship among hormone, the mediator and the biological response. Amplification of the hormonal signal by enzyme cascades. G-proteins signal transducers couples membrane receptor to specific enzymes and ion channels. Called g-proteins because they bind to gtp (guanosine triphosphate) and act as gtpase: camp & cgmp in cytosol, they"re generated by cyclases, phospholipids, ca+, others. Gtpase: g protein is a molecular switch with a built-in automatic timer. When bound to gdp, the switch is in the off position; when bound to atp, the switch is on .