regulation of transcription factor activity Flashcards
how can transcription factor activities be directly regulated?
by lipid hormones
how can transcription factor activities be indirectly regulated?
by cell surface receptors and intracellular signal transduction cascades
when cells send signals to other cells when directly regulating transcription factor activities, what is expressed?
lipid-soluble hormone
when cells send signals to other cells when indirectly regulating transcription factor activities, what is expressed?
lipid-insoluble peptide hormone
where do lipid soluble hormones diffuse? through what? bind to?
into the cell through cell membrane, bind to lipid hormone receptors/transcription activators
true or false. consensus sequences have variability.
true
what is the transactivation domain of GR replaced by?
g-galactosidase
what needs to be present for the GR to translocate to the nucleus?
hormone-binding domain
where does TAT bind? what does it prevent?
binds to the 5’ end of paused mRNA
prevents PTEFb from phosphorylating
after eukaryotic activators/repressors bind to DNA elements in promoters, how do they affect gene expression?
they recruit multi-subunit co-activator/co-repressor complexes that modulate chromatin structure.
what do activators and co-activators stimulate?
the assembly of pre initiation complexes, and move nucleosomes away from the promoters.
what makes up a nucleosome? what are they called
8 histones
2 each of H2A, H2B, H3 and H4
which part of the histones makes up the highly structured nucleosome?
core domains
do histone N-termini protrude away or towards from the histone core?
away
what are the n-termini modified by?
post-transcriptional modifications
