MED27 explained

Symbol:	Med27
Med27
Pfam:	PF11571
Interpro:	IPR021627

Mediator of RNA polymerase II transcription subunit 27 is an enzyme that in humans is encoded by the MED27 gene.^{[1] [2]} It forms part of the Mediator complex.

The ubiquitous expression of Med27 mRNA suggests a universal requirement for Med27 in transcriptional initiation. Loss of Crsp34/Med27 decreases amacrine cell number, but increases the number of rod photoreceptor cells.^[3]

The activation of gene transcription is a multistep process that is triggered by factors that recognize transcriptional enhancer sites in DNA. These factors work with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The protein encoded by this gene is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, along with TFIID, is required for efficient activation by SP1. This protein is also a component of other multisubunit complexes e.g. thyroid hormone receptor-(TR-) associated proteins which interact with TR and facilitate TR function on DNA templates in conjunction with initiation factors and cofactors.

See also

• Mediator complex

Further reading

• Roth J, Krause M . [Relation between manifest bronchial obstruction and bronchial hyperreactivity (author's transl)] . Zeitschrift für Erkrankungen der Atmungsorgane . 146 . 1 . 12–6 . 1977 . 1020353 .
• Gress TM, Müller-Pillasch F, Geng M, etal . A pancreatic cancer-specific expression profile. . Oncogene . 13 . 8 . 1819–30 . 1996 . 8895530 .
• Malik S, Gu W, Wu W, etal . The USA-derived transcriptional coactivator PC2 is a submodule of TRAP/SMCC and acts synergistically with other PCs. . Mol. Cell . 5 . 4 . 753–60 . 2000 . 10882111 . 10.1016/S1097-2765(00)80254-3 . free .
• Strausberg RL, Feingold EA, Grouse LH, etal . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . free .
• Sato S, Tomomori-Sato C, Banks CA, etal . Identification of mammalian Mediator subunits with similarities to yeast Mediator subunits Srb5, Srb6, Med11, and Rox3. . J. Biol. Chem. . 278 . 17 . 15123–7 . 2003 . 12584197 . 10.1074/jbc.C300054200 . free .
• Sato S, Tomomori-Sato C, Banks CA, etal . A mammalian homolog of Drosophila melanogaster transcriptional coactivator intersex is a subunit of the mammalian Mediator complex. . J. Biol. Chem. . 278 . 50 . 49671–4 . 2004 . 14576168 . 10.1074/jbc.C300444200 . free .
• Tomomori-Sato C, Sato S, Parmely TJ, etal . A mammalian mediator subunit that shares properties with Saccharomyces cerevisiae mediator subunit Cse2. . J. Biol. Chem. . 279 . 7 . 5846–51 . 2004 . 14638676 . 10.1074/jbc.M312523200 . free .
• Ota T, Suzuki Y, Nishikawa T, etal . Complete sequencing and characterization of 21,243 full-length human cDNAs. . Nat. Genet. . 36 . 1 . 40–5 . 2004 . 14702039 . 10.1038/ng1285 . free .
• Humphray SJ, Oliver K, Hunt AR, etal . DNA sequence and analysis of human chromosome 9. . Nature . 429 . 6990 . 369–74 . 2004 . 15164053 . 10.1038/nature02465 . 2734081 . 2004Natur.429..369H .
• Sato S, Tomomori-Sato C, Parmely TJ, etal . A set of consensus mammalian mediator subunits identified by multidimensional protein identification technology. . Mol. Cell . 14 . 5 . 685–91 . 2004 . 15175163 . 10.1016/j.molcel.2004.05.006 . free .
• Gerhard DS, Wagner L, Feingold EA, etal . The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 .

Notes and References

1. Ryu S, Zhou S, Ladurner AG, Tjian R . The transcriptional cofactor complex CRSP is required for activity of the enhancer-binding protein Sp1 . Nature . 397 . 6718 . 446–50 . Feb 1999 . 9989412 . 10.1038/17141 . 1999Natur.397..446R . 4405569 . 11858/00-001M-0000-0019-A36A-8 . free .
2. Web site: Entrez Gene: CRSP8 cofactor required for Sp1 transcriptional activation, subunit 8, 34kDa.
3. Dürr K, Holzschuh J, Filippi A, Ettl AK, Ryu S, Shepherd IT, Driever W . Differential roles of transcriptional mediator complex subunits Crsp34/Med27, Crsp150/Med14 and Trap100/Med24 during zebrafish retinal development . Genetics . 174 . 2 . 693–705 . October 2006 . 16582438 . 1602071 . 10.1534/genetics.105.055152 .