BIO 1140 Lecture Notes - Lecture 6: Vascular Endothelial Growth Factor, Platelet-Derived Growth Factor, Phospholipid

40 views2 pages
Topic 6 - Signal Transduction (Part 2)
Cell Biology
Kristen Batten, 8616820
Thursday, February 16th, 2017
- Membrane Potential:
o The uneven distribution of ions creates potential energy: it can be measure in
mV (milliVolts)
o When channels open/close. Changing this ionic distribution, potential energy,
and hence the membrane potential, changes
o Can lead to action potentials
- Ion-Channel-Coupled Receptors:
o They regulate the flow of ions across the cell membrane
o Different receptors regulate different ions
o They are quite varied in shape
o Composed of multiple subunits that surround a central channel through while
the ions flow
- TM receptors 1: ligand gated ion channels:
o Very important for the nervous system used by many NTs
o Some channels are specific to certain ions, others are less discerning
o Voltage-gated ion channels: are similar. They rely on change in voltage to
open/close rather than ligand binding
- Acetylcholine:
o Ach is a very important neurotransmitter
o Can be excitatory or inhibitory (depending on receptor/cascade)
o Can use 2 types of receptors (AChR) (ionotropic or metabotropic):
Ligand-gated ion channels (nicotinic receptors) or..
GPCR’s uscariic receptors
o Ach ligand-gated ion channels:
When both binding sites are filled, conformation changes, pore opens
and lets ions through, mostly Na+ and Ca2+ into the cell, some K+ goes
out
This changes the electrochemical gradient or membrane potential and
can lead to an Action Potential
- TM receptors 2: Receptor enzymes:
o Intracellular catalytic domain acts as an enzyme
o Initiates a cascade of phosphorylation-deposphorylation that amplifies the
ligands impact on a target cell
o 3 main classes focus on Tyrosine Kinase receptors
- Tyrosine kinase receptors (Tyr-K; RTK)
o Largest family of enzyme receptors (over 20 types)
o Involved in pathways linked to survival, growth, proliferation and metabolism
o Activation requires dimerization and auto-phosphorylation
o Signaling is initiated via an area called an SH2 domain (Src homology)
find more resources at oneclass.com
find more resources at oneclass.com
Unlock document

This preview shows half of the first page of the document.
Unlock all 2 pages and 3 million more documents.

Already have an account? Log in

Document Summary

Membrane potential: the uneven distribution of ions creates potential energy: it can be measure in mv (millivolts, when channels open/close. Changing this ionic distribution, potential energy, and hence the membrane potential, changes: can lead to action potentials. Ion-channel-coupled receptors: they regulate the flow of ions across the cell membrane, different receptors regulate different ions, they are quite varied in shape, composed of multiple subunits that surround a central channel through while the ions flow. Tm receptors 1: ligand gated ion channels: very important for the nervous system used by many nts, some channels are specific to certain ions, others are less discerning, voltage-gated ion channels: are similar. They rely on change in voltage to open/close rather than ligand binding. Acetylcholine: ach is a very important neurotransmitter, can be excitatory or inhibitory (depending on receptor/cascade, can use 2 types of receptors (achr) (ionotropic or metabotropic): Gpcr"s (cid:894)(cid:373)uscari(cid:374)ic receptors(cid:895: ach ligand-gated ion channels:

Get access

Grade+
$10 USD/m
Billed $120 USD annually
Homework Help
Class Notes
Textbook Notes
40 Verified Answers
Study Guides
Booster Classes
Class+
$8 USD/m
Billed $96 USD annually
Homework Help
Class Notes
Textbook Notes
30 Verified Answers
Study Guides
Booster Classes