Prokaryotic and Eukaryotic gene regulation Flashcards
cis-regulating factors
are DNA sequences on the same DNA strand as the gene they regulate
trans-regulating factors
are proteins that bind to cis-element DNA sequences
what are the different proteins involved in prokaryotic gene regulation and what do they do?
there are activators and repressors that control the rate of RNA synthesis (transcription)
what do activators do and what type of control do they have?
they recruit RNA polymerase and increase transcription with a positive control
what are repressors and what type of control do they have?
they block RNA polymerase and inhibit transcription with a negative control
what is the role of small effector molecules in transcriptional regulation, and the 3 different types
they exert the effects by binding to activator or repressor.
inducers, corepressors, inhibitors
what do inducers do
they either:
- bind to activators and cause them to bind to DNA
- bind to repressors and prevent them from binding to DNA
what do corepressors do
they bind to activators and cause them to bind to DNA
what do inhibitors do
bind to activators and prevent them from binding to DNA
what is an operon
a regulatory unit containing multiple genes under the control of a single promoter
the parts of lac operon
promoter, CAP site, operator, protein-encoding genes ( lacZ, lacY, lacA), terminator
encodes for a repressor protein
Lacl
why cant RNA polymerase reach the promoter when the repressor is bound
repressor prevents the RNA polymerase to continue transcription because of its lack of small effector molecules binding to repressor
what are eukaryotic transcription factors
they are proteins that aid in regulating RNA polymerase’s ability to transcribe a gene
general transcription factors are required for?
binding of RNA polymerase to the core promoter
