Transcription Regulation (Eukaryotes) Flashcards
Core Promoter
Basal transcription factors that bind RNAPii and indicate non-sequence specific starting point for transcription.
Proximal Promoter
Sequence specific binding site for regulatory factors of transcription.
TATA Boxes
Sequence in core promoter that binds TFIID
TFIID
Composed of 15 different polypeptides, one of which binds TATA sequence (TBP) and 14 other TAFs that bind initiator and downstream promoter elements to recruit PIC assembly.
Mediator
Intermediate helper that binds to UNPHOSPHORYLATED RNAPii c-terminal domain in formation of the PIC.
When CTD is phosphorylated, RNAPii is signaled to begin transcription cycle and it unbinds mediator so it can move off the promoter.
CTD
Seven amino acid motif pseudo repeat containing 3 Ser residues available for phosphorylation. Change in phosphorylation status of varying residues indicates where in the gene RNAP is and helps transition from initiation to elongation to termination.
Ex: capping enzymes –> change in phosphorylation status replaces them with splicing machinery –> change in phosphorylation status replaces them with cleavage and polyadenylation machinery
Capping enzymes are additive, elongation enzymes are synergistic.
HPA Axis
Hypothalamus sends CRH to pituitary –> Pituitary sends ACTH to adrenal cortex –> release of cortisol which acts as TF in liver and pancreas to increase gluconeogenesis and glycogen metabolism through change in gene expression.
Glucocorticoid Receptor
Cortisol binds chaperone proteins to make it soluble and diffuses across membrane –> binds GR steroid hormone receptor in cytoplasm NOT membrane –> enters nucleus
RNA-Seq
Reverse transcriptase makes DNA from RNA template, provides gene expression data in specific cell types.
Tells you both if levels of RNA are correct AND is RNA sequence is correct.
