BI110 Chapter Notes - Chapter 20: Cell Division, Cell Adhesion Molecule, Dna-Binding Domain
Document Summary
Intracellular nuclear and cytoplasmic receptors directly bind smaller, lipid soluble molecules that readily diffuse through the cell membrane. Enzyme linked receptors: dimerize to transmit a signal, contains extracellular domain that binds ligands, binds to two receptors, dimerize and form a complex, allows phosphorylation, phosphorylation leads to a signal transduction. Facilitates inactive exchange of gdp for gtp: g protein, now activated, diffuses along the membrane and activated enzymes to trigger the next signal transduction event. Signal transduction- overall process by which cells respond to extracellular signaling molecules or other stimuli by executing a physiological response. Phases of cell signaling: reception, ligand binds to receptor, transduction, receptor activated signal transduction molecule, response, signal transduction molecule initiates signaling cascade. Signal molecules: usually hydrophilic that cant cross pm, hormones, neurotransmitters, receptors. Integral membrane glycoproteins: responses usually rapid, short lived events. Integral membrane proteins-->glycoproteins: binding of a signalling molecule, specific fit, just like an enzyme binding substrate.
