| Term | Definition |
|---|
| 2 main types of regulation | 1) modulate protein amounts 2) modulate protein activity |
| protein activity | inactivate or activate a protein that was already made - ex's are allosteric inhib, phosphorylation, covalent modification, methylation, acetylation, protein degradation |
| protein amounts | cell control of synthesis or degradation of the protein - many variables to control the quantity |
| lac operon enzyme regulation | modulate protein amounts; encode enzymes for lactose utilization and catabolism. Regulation is for efficiency and energy conservation because lactose isn't a common sugar |
| kinase | enzymes that phosphorylate other proteins/acceptor molecules |
| phosphatases | enzymes that remove other phosphate groups, regulate signal transduction pathways too |
| lacZYA | genes encoding enzymes for lactose metabolism |
| LacI | lac repressor protein, produced constitutively |
| promoter | DNA region where DNA pol binds |
| operator | DNA region where lac repressor protein binds |
| (allo)lactose | inducer protein that binds the lac repressor |
| regulations that decrease amounts of enzyme | transcriptional repression, attenuation, translational repression |
| regulations that increase amounts of enzyme | transcriptional activation, promoter recognition, transcriptional enhancement |
| attenuation | specific type of allosteric inhibition that prematurely terminates transcription once product is abundant; specific to prokaryotes, |
| trp operon | trpA-E genes encode enzymes to synthesize tryptophan |
| trpL | leader peptide 14 aa long, upstream to trpA-E, has 2 adjacent trps. |
| attenuation process of trp operon | when tryptophan is scarce, ribosome stalls/pauses, antiterminator signals to RNA pol to keep transcribing. If trp is abundant, ribosome won't pause and terminator structure forms, signalling RNA pol to stop transcription and fall off |
| secondary regulation of attenuation in trp operon | regulate amino acid biosynthesis operons in addition to trp |
| three most commonly observed regulations for protein amounts | transcription regulation, transcriptional fusion, post-transcriptional regulation - mRNA stability, post-translational regulation - enzyme stability |
Combine with other sets
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