In
gene expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. ...
, DSIF (
DRB
Deshastha Brahmin is a Hindu Brahmin subcaste mainly from the Indian state of Maharashtra and northern area of the state of Karnataka. Other than these states, according to authors K. S. Singh, Gregory Naik and Pran Nath Chopra, Deshastha Bra ...
Sensitivity Inducing Factor) is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
that can either negatively or positively affect transcription by
RNA polymerase II
RNA polymerase II (RNAP II and Pol II) is a multiprotein complex that transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA. It is one of the three RNAP enzymes found in the nucleus of eukary ...
(Pol II). In one case of negative regulation, it can interact with
negative elongation factor (NELF) to promote the stalling of Pol II at some genes. This stalling is relieved by
P-TEFb
The positive transcription elongation factor, P-TEFb, is a multiprotein complex that plays an essential role in the regulation of transcription by RNA polymerase II (Pol II) in eukaryotes. Immediately following initiation Pol II becomes trapped in ...
. In humans, DSIF is composed of
hSPT4 and
hSPT5 (SPT4 and SPT5 are homologs in yeast).
The complex locks the RNAP clamp into a closed state to prevent the elongation complex (EC) from dissociating. The Spt5
NGN domain
NGN can refer to :
* Neurogenins, a family of bHLH transcription factors involved in specifying neuronal differentiation
* Nigerian naira, currency by ISO 4217 code
* Noida Greater Noida Expressway, in Delhi, India
;Telecommunications
* Next G ...
helps anneal the two strands of DNA upstream. The single
KOW domain
Kow or KOW may refer to:
* Kow (bull), a legendary bull in Meitei mythology of Manipur
* Ganzhou Huangjin Airport, IATA code KOW
* Ganzhou Huangjin Airport (former), IATA code KOW until replaced by new airport in 2008
* Kow Swamp, Victoria, ...
in bacteria and archaea anchors a
ribosome to the RNAP.
In bacteria, the homologous complex only contains ''NusG'', a Spt5 homolog. Archaea have both proteins.
References
{{Reflist
Gene expression