BIO 327 Chapter Notes - Chapter 5: Dna Replication, Transcription Factor Ii D, Heterotetramer
Document Summary
Combinations of regulation on synthesis points and post-translational modifications are one way that eukaryotes can make complicated tissues/organisms without needing more genes combinatorial control: ex. Once gtp is hydrolyzed to gdp, the activities of gtp binding proteins are recycled because gdp is released and gtp is rebound. Proteasomes: multi-protein complexes found in cytosol and nucleus. Made of regulatory subunits and proteolytic enzymes. Function to receive and degrade cellular proteins that are damaged or that have been targeted for degradation by modification by ubiquitin. Dedicated to degradation of proteins found in membranes or soluble proteins imported into the cell. Involved localization, some transcription factors are held in the cytosol until signals cause modifications that allow their entry into the nucleus where they can function. Assembly: proteins are typically not active until they have assembled into quaternary structures. Hemoglobin alpha and beta subunits are non-functional along until they assemble into the heterotetramer. Lipid addition: anchors or localizes proteins to different membranes.
