Intercellular Communication Overview
Autocrine AKA: Juxtacrine
Endocrine
Paracrine, Autocrine Nervous Juxtacrine
Same signal Many different effects Different Receptors Different Intracellular Events Same signal Many different effects
ACTIVITY
Signaling Through Intracellular Receptors Hydrophobic Signaling Molecules
nitric oxide
Transcription Factor
Enzyme
Signaling Through Surface Receptors Hydrophilic Signaling Molecules
epidermal growth factor peach lactone histamine insulin acetylcholine
messengers
Amplify Signal Transduction
Ligand-gated channels
Enzyme & Enzyme-linked Receptors Receptor Tyrosine Kinases
(Receptor Tyrosine Kinase) E.g., Epidermal Growth Factor (EGF) Insulin IGF, FGF, HGF, PDGF P Cross-Phosphorylation (Receptor Tyrosine Kinase)
Protein Domain Binding Partner Structure SH2 (Src Homology 2) Phosphotyrosine SH3 (Src Homology 3) Poly-Proline PH (Plekstrin Homology) Phospho-Phosphotidylinositol (PI2P, PI3P) PTB (Phosphotyrosine Binding)
Ras Activation
EGF SH2 SH3 Son of Sevenless (SOS; a GNEF for Ras) Grb2 (an adapter protein) Son of Sevenless (SOS; a GNEF for Ras)
Cell Division
PI Kinase Activation
Phosphatidylinositol Kinase
PH PH
PH PH
AKT
G-Protein Linked Receptors GPCRs
Extracellular Space
Ion Channel Activation bg
Adenylyl Cyclase Activation
adenylyl cyclase
adenylyl cyclase ATP cAMP
(protein kinase A)
Phospholipase C Activation