Foundations of Biology Exam 4: Control of Gene Expression I- Prokaryotes

differential gene expression

a biochemical process that determines which genes respond to which signals or triggers depending on the condition

transcription factors

recognize a specific sequence of bases in DNA based on shape and partial charge to make hydrogen bonds; the main thing that controls how DNA in transcribed

transcriptional control

level of gene expression regulation in bacteria; changes the frequency of transcription initiation

translational control

level of gene expression regulation in bacteria; change the mRNA lifespan (stability) or change the translation rate, or how often translation begins

post-translational control

level of gene expression regulation in bacteria; change protein activity by chemical modifications

negative control

regulatory protein shuts down transcription; blocks RNA polymerase

positive control

regulatory protein triggers transcription

operon

a group of genes that are transcribed together and regulated by a shared promoter and operator

inducer

a small molecule that triggers transcription of a gene; works with a transcription factor

operator

a sequence of DNA that a transcription factor binds to

activator

transcription factor protein that promotes transcription

repressor

transcription factor protein that decreases transcription

regulon

a set of separate genes and operons that contain the same regulatory sequences and are controlled by a single type of regulatory protein; the cell only need to make one TF that will repress and activate all the genes

SOS regulon

when DNA is damaged; repressors are cleaved of many operators at once to create a fast response