Transcript BIO131 Exam 3 Results

Cell to Cell Communication
John Ireland
Cell Signaling Overview
Exterior of Cell
Interior of Cell
Cellular
Response
Membrane Receptor
Signal
Transduction
Pathway
Intracellular Receptor
Types of Cell-Cell Signaling
Direct Contact
Paracine Signaling
Endocrine Signaling
Synaptic Signaling
How does signaling happen?
Phosphorylation
Unactivated Protein
Activated Protein
Phosphorylation actives Proteins
Phosphates are added to amino
acids.
Specifically either
Serine/Threonine or Tyrosine
Phosphates are added by Protein
Kinases (specific enzymes)
Dephosphorylation by
Phosphotases deactivate the
proteins
Types of Receptors in Cells
Intracellular
Chemically Gated
Ion Channels
Enzymatic
G-Protein
Coupled
Intracellular Receptors
Triggered by Hydrophobic
Ligands (i.e. Hormones)
Complex Proteins with
Multiple Domains.
Blocked by an Inhibitor till
Activation
Mechanism
Exterior
Cytoplasm
Receptor
w/
Inhibitor
Nucleus
Hormone
Inhibitor
Gene
Activation
Protein Kinase Receptors
Binding of external ligands
causes internal phosphorylation
Phosphorylation actives adapter
proteins
Adapter Proteins activate
response.
Insulin Receptor Mechanism
Exterior
Cytoplasm
Insulin
Response
Protein
Insulin
Insulin
Receptor
Glucose
Glycogen
Synthase
Glycogen
G-Protein Coupled Receptor
cAMP Signal Pathway
Exterior
Adenylate
Cyclase
GPCR
G Protein
w/
GDP
(inactive)
G Protein
Α Subunit
w/
GTP
(active)
ATP
cAMP
Cytoplasm