Editing Transcription factor (section)

== Mechanism ==
Transcription factors bind to either [[enhancer (genetics)|enhancer]] or [[promoter (biology)|promoter]] regions of DNA adjacent to the genes that they regulate based on recognizing specific DNA motifs.  Depending on the transcription factor, the transcription of the adjacent gene is either [[Downregulation and upregulation|up- or down-regulated]].  Transcription factors use a variety of mechanisms for the regulation of gene expression.<ref name="pmid11758455">{{Cite journal |vauthors=Gill G |year=2001 |title=Regulation of the initiation of eukaryotic transcription |journal=Essays in Biochemistry |volume=37 |pages=33–43 |doi=10.1042/bse0370033 |pmid=11758455}}</ref>  These mechanisms include:
* stabilize or block the binding of RNA polymerase to DNA{{cn|date=March 2024}}
* catalyze the [[acetylation]] or deacetylation of [[histone]] proteins.  The transcription factor can either do this directly or recruit other proteins with this catalytic activity.  Many transcription factors use one or the other of two opposing mechanisms to regulate transcription:<ref name="pmid11909519">{{Cite journal |vauthors=Narlikar GJ, Fan HY, Kingston RE |date=February 2002 |title=Cooperation between complexes that regulate chromatin structure and transcription |journal=Cell |volume=108 |issue=4 |pages=475–87 |doi=10.1016/S0092-8674(02)00654-2 |pmid=11909519 |s2cid=14586791 |doi-access=free}}</ref>
** [[histone acetyltransferase]] (HAT) activity – acetylates [[histone]] proteins, which weakens the association of DNA with [[histone]]s, which make the DNA more accessible to transcription, thereby up-regulating transcription
** [[histone deacetylase]] (HDAC) activity – deacetylates [[histone]] proteins, which strengthens the association of DNA with histones, which make the DNA less accessible to transcription, thereby down-regulating transcription
* recruit [[coactivator (genetics)|coactivator]] or [[corepressor (genetics)|corepressor]] proteins to the transcription factor DNA complex<ref name="pmid10322133">{{Cite journal |vauthors=Xu L, Glass CK, Rosenfeld MG |date=April 1999 |title=Coactivator and corepressor complexes in nuclear receptor function |journal=Current Opinion in Genetics & Development |volume=9 |issue=2 |pages=140–7 |doi=10.1016/S0959-437X(99)80021-5 |pmid=10322133}}</ref>