Ch 14 Regulation of Cellular Processes

Gene that is expressed at equal levels at all times

Genes whose expression can be increased by a regulatory molecule

Small molecule that stimulates the syn of an inducible enzyme

Gene whose product is a protein whose level drops in the presence of a small repressor molecule. If part of biosyn pathway——> repressor is usually the product of that pathway

Small molecule that binds a transcription repressor protein, activating it and inhibiting enzyme production

Proteins that bind near promoter region to help initiate and/or prevent transcription of a gene. (Usually dimers)

Part of a protein with specific shape and function

Reg of transcription by repressor protein. When bound, trans repressed

Control of transcription by activator protein. When bound level of trans increased

Area of DNA that repressor binds to (overlaps or downstream of promoter) prevents RNA pol binding or movement

DNA seq where activators bind (usually upstream of promoter) allows RNA pol to bind

Related structural genes, a promoter, an operator and/or activator binding site that controls expression of the operon

Catabolite activator protein. Regulates the lac operon in regards to the presence of glucose (Will repress if glucose is present)

Collection of related operons controlled by activator proteins

Regulatory mech that suppresses the expression and activity of metabolic systems of a secondary C source when preferred source is present

When transcription is stopped within the leader

Repressor does not block transcription——> trans begins and leader is translated.——> if trp present the two trp codons filled trans proceeds to stop codon——> 3-4 loop (term loop) forms RNA pol booted from DNA

Repressor does not bind,trans begins——> as translation begins not enough charged trp tRNA to fill 2 codons, Ribosome pauses——> b/c of pause 2-3 loop forms——> blocks formation of 3-4 term loop——> transcription of trp operon proceeds

Small RNA. Binds to mRNA to act in regulation. Can be inhibiting or inducing

SsRNA with bases complimentary to a segment of a target RNA molecule. Usual alters target when bound

Allolactose binds repressor protein, inactivating it——> CAP activated with cAMP bound binds CAP site——> RNA pol binds promoter stabilized by bound CAP and transcription proceeds

Allolactose binds regulator protein and inactivates it——> cAMP does not bind and activate CAP——> CAP does not bind CAP site, RNA pol can not bind——> no transcription

Repressor remains activated since no Allolactose to bind it——> CAP is activated by cAMP, binds CAP site——> RNA pol can bind but can not proceed with transcription b/c blocked by repressor protein