BIO 3153 Lecture Notes - Lecture 19: Adenylyl Cyclase, Long-Term Potentiation, Calmodulin

• School: University of Ottawa
• Department: Biology
• Course: BIO 3153
• Professor: Michael Jonz

Document Summary

Lecture 19 cell communication/signaling iii: four other forms of signaling. 1) ca2+ signaling (cicr: 3 mechanisms to release ca2+ from intracellular *important for muscle contractions, secretion from vesicles. 2) calmodulin activation: calmodulin is a ca-binding protein and transducer of ca signals, modifies activity of target enzymes (ex. adenylyl cyclase) - binds to ca when cytosolic ca reaches 10-6m and releases when 10-7m, steps: 1) 2 ca2+ ions bind to 2 hand regions (aspartic and glutamic acid) 3) hands bind to calmodulin binding sites to modify activity. 3) cam-kinase ii activation: large enzyme of 12 subunits, activity dependent on ca/cam binding, has autophosphorylation activity, important in long term potentiation (learning, steps: 1) interaction between catalytic and regulatory domains make it inactive. 2) binding of ca/cam leads to partial activation. Phosphorylation of non-nmda receptors & increased activity. Mobilization of more non-nmda receptors to plasma membrane. 4) ca independent activation continues until deactivation by protein phosphatase.