Evaluate how regulation is accomplished through intracellular signalling:

Signalling involves transduction steps that can alter enzymatic activity: e.g. GP, the binding properties of an effector protein: e.g calmodulin, or the assembly of a protein complex: e.g. trimeric G-protein

Understand some important principles of signalling:

Second messengers are small molecules that are produced or released to transiently activate proteins. E.g. cAMP is generated downstream of adrenaline signalling and activates PKA. There are many different GPCRs, these couple to a variety of G-proteins, different cells use this for different functional outputs

Define how signalling pathways can modulate important physiological functions, and how these are involved in diseases:

Glycogen metabolism is regulated by adrenaline signalling (fight or flight response) Adrenaline can activate different types of responses dependent on the available downstream signalling components, and cAMP can have different functions in tissues depending on the targets available in each cell

Describe the major constituents of signaling cascades and their mode of action:

Second messengers are small molecules signal transducers. GPCRs are major cell surface receptors. G-proteins are molecular switches. Kinases (e.g. PKA) phosphorylate target proteins to alter their activities – e.g. GPK, GS, PP

	Created by Chloe Cavarretta over 5 years ago

Cell Biology Lectures 5-7

3. Signalling