BISC207 Lecture Notes - Lecture 16: G Protein–Coupled Receptor, Autocrine Signalling, Paracrine Signalling

• School: University of Delaware
• Department: Biological Sciences
• Course: BISC207
• Professor: Nauen Jennifer

Document Summary

Signal transduction (=conversion to a dif form) Cell response to the signal- enzyme activation, cytoskeletal change, or transcription. Nonpolar signals diffuse through the membrane, bind to intracellular receptors, Polar molecules interact with transmembrane receptors since they can transfuse into the cell. Ligand binds noncovalently; activates receptor, ligand is unchanged. Signalling cell lacks receptors; target cells are local. Juxtacrine signaling is contact dependent both signal and receptor are bound to the plasma membrane. G protein coupled receptors associate with other proteins when activated. Gpcr is associated with inactive g protein. G protein releases gdp and binds to gtp; splits apart and away from the gpcr. When gtp binds to a protein, the protein changes shape. When activated, they often phosphorylate themselves themselves or other proteins. Signal/ ligand (1st messenger ) binds to receptor. Small molecules or ions (=2nd messengers) are produced which convey info in cell. 2nd messengers allow signal amplification and speedy response. Receptor required for a cell to respond.