Problem Set 5 Q&A

Problem Set 5 Q&A - BIPN 140 Fall 2008 Problem Set 5 1....

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
BIPN 140 Fall 2008 Problem Set 5 1. Assuming that action potentials reach the presynaptic membrane, what are three Ca 2+ -related manipulations that can be done to prevent vesicle release? > use dihydropyridine to block voltage-gated Ca 2+ channels, preventing Ca 2+ from entering the presynaptic terminal. > remove extracelluar calcium, no Ca 2+ enters the presynaptic membrane when the channels open. >alter the sequence encoding synaptotagmin so that it can’t bind Ca 2+ . 2. If the intracellular and extracellular concentrations of Na+ were reversed, would AMPA still be an excitatory receptor? Why or why not? If the intracellular and extracellular concentrations of Na+ were reversed, both the electrical and chemical gradient would favor the efflux of Na+ from the cell; thus the reversal potential would be below threshold, making it an inhibitory receptor. 3. Give all the steps in vesicle trafficking cycle, the main players that are responsible for each step and the function of each player. 1. Reserve pool - actin and synapsins are holding the vesicles for preparation of docking 2. Mobilization - phosphorylation of synapsin by CaMKII allows synapsin to dissociate from the reserve pool. The vesicles are now free to dock. 3. Priming - snare complex (the interaction between synaptobrevin from the vesicle and SNAP - 25 and syntaxin from the plasma membrane) forms, pulling the vesicle membrane close to the plasma membrane. 4. Fusion - Calcium binds to the synaptotagmin on the vesicle triggering the release of neurotranmitters. 5.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Problem Set 5 Q&A - BIPN 140 Fall 2008 Problem Set 5 1....

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online