Transcription factor II D

RNA polymerase II holoenzyme is a form of eukaryotic RNA polymerase II that is recruited to the promoters of protein-coding genes in living cells. It consists of RNA polymerase II, a subset of general transcription factors, and regulatory proteins known as SRB proteins. Transcription factor II D (TFIID) is one of several general transcription factors that make up the RNA polymerase II preinitiation complex.[1] Before the start of transcription, the transcription Factor II D (TFIID) complex, binds to the TATA box in the core promoter of the gene.

TFIID is itself composed of several subunits called TBP-associated factors (TAFs, of which there are 16) and the TATA Binding Protein (TBP). In a test tube, only TBP is necessary for transcription at promoters that contain a TATA box.[2] TAFs, however, add promoter selectivity, especially if there is no TATA box sequence for TBP to bind to. TAFs are included in two distinct complexes, TFIID and B-TFIID.[3] The TFIID complex is composed of TBP and more than eight TAFs. But, the majority of TBP is present in the B-TFIID complex, which is composed of TBP and TAFII170 (BTAF1) in a 1:1 ratio.[4]

TFIID (GTF2D)

  1. coordinates the activities of more than 70 polypeptides required for initiation of transcription by RNA polymerase II,
  2. binds to the core promoter to position the polymerase properly,
  3. serves as the scaffold for assembly of the remainder of the transcription complex, and
  4. acts as a channel for regulatory signals.

Subunits in the TFIID complex include:[2]

See also

References

  1. ^ Lewin, Benjamin (2004). Genes VIII. Upper Saddle River, NJ: Pearson Prentice Hall. pp. 636–637. ISBN 0-13-144946-X. 
  2. ^ a b Lee TI, Young RA (2000). "Transcription of eukaryotic protein-coding genes". Annu. Rev. Genet. 34: 77–137. doi:10.1146/annurev.genet.34.1.77. PMID 11092823. 
  3. ^ "NCBI Entrez GeneID: 9044 BTAF1 BTAF1 RNA polymerase II, B-TFIID transcription factor-associated, 170kDa (Mot1 homolog, S. cerevisiae)". http://www.ncbi.nlm.nih.gov/sites/entrez. 
  4. ^ Timmers HTM, Meyers RE, Sharp PA (Sep 1992). "Composition of transcription factor B-TFIID". Proc Natl Acad Sci USA. 89 (17): 8140–4. doi:10.1073/pnas.89.17.8140. PMC 49872. PMID 1387711. http://www.pnas.org/content/89/17/8140.full.pdf+html. 

External links

Signaling pathways
Agents
By location
Other concepts
B trdu: iter (nrpl/grfl/cytl/horl), csrc (lgic, enzr, gprc, igsr, intg, nrpr/grfr/cytr), itra (adap, gbpr, mapk), calc, lipd; path (hedp, wntp, tgfp+mapp, notp, jakp, fsap, hipp, tlrp)