RNA polymerase II subunit B4 explained

DNA-directed RNA polymerase II subunit RPB4 is an enzyme that in humans is encoded by the POLR2D gene.^[1]

This gene encodes the fourth-largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. In yeast, this polymerase subunit is associated with the polymerase under suboptimal growth conditions and may have a stress protective role. A sequence for a ribosomal pseudogene is contained within the 3' untranslated region of the transcript from this gene.^[2]

Further reading

• Jeang KT . Tat, Tat-associated kinase, and transcription. . J. Biomed. Sci. . 5 . 1 . 24–7 . 1998 . 9570510 . 10.1007/BF02253352 .
• Yankulov K, Bentley D . Transcriptional control: Tat cofactors and transcriptional elongation. . Curr. Biol. . 8 . 13 . R447–9 . 1998 . 9651670 . 10.1016/S0960-9822(98)70289-1 . 15480646 . free . 1998CBio....8.R447Y .
• Romano G, Kasten M, De Falco G, etal . Regulatory functions of Cdk9 and of cyclin T1 in HIV tat transactivation pathway gene expression. . J. Cell. Biochem. . 75 . 3 . 357–68 . 2000 . 10536359 . 10.1002/(SICI)1097-4644(19991201)75:3<357::AID-JCB1>3.0.CO;2-K . 43685090 .
• Marcello A, Zoppé M, Giacca M . Multiple modes of transcriptional regulation by the HIV-1 Tat transactivator. . IUBMB Life . 51 . 3 . 175–81 . 2002 . 11547919 . 10.1080/152165401753544241 . 10931640 . free .
• Stevens M, De Clercq E, Balzarini J . The regulation of HIV-1 transcription: molecular targets for chemotherapeutic intervention. . Med Res Rev . 26 . 5 . 595–625 . 2007 . 16838299 . 10.1002/med.20081 . 7168390 .
• Harrich D, McMillan N, Munoz L, etal . Will diverse Tat interactions lead to novel antiretroviral drug targets? . Current Drug Targets . 7 . 12 . 1595–606 . 2007 . 17168834 . 10.2174/138945006779025338 .
• Kato H, Sumimoto H, Pognonec P, etal . HIV-1 Tat acts as a processivity factor in vitro in conjunction with cellular elongation factors. . Genes Dev. . 6 . 4 . 655–66 . 1992 . 1559613 . 10.1101/gad.6.4.655 . free .
• Southgate C, Zapp ML, Green MR . Activation of transcription by HIV-1 Tat protein tethered to nascent RNA through another protein. . Nature . 345 . 6276 . 640–2 . 1990 . 2190099 . 10.1038/345640a0 . 1990Natur.345..640S . 4233742 .
• Richard Gaynor . Wu-Baer F, Sigman D, Gaynor RB . Specific binding of RNA polymerase II to the human immunodeficiency virus trans-activating region RNA is regulated by cellular cofactors and Tat. . Proc. Natl. Acad. Sci. U.S.A. . 92 . 16 . 7153–7 . 1995 . 7638159 . 10.1073/pnas.92.16.7153 . 41297 . 1995PNAS...92.7153W . free .
• Herrmann CH, Rice AP . Lentivirus Tat proteins specifically associate with a cellular protein kinase, TAK, that hyperphosphorylates the carboxyl-terminal domain of the large subunit of RNA polymerase II: candidate for a Tat cofactor. . J. Virol. . 69 . 3 . 1612–20 . 1995 . 7853496 . 10.1128/JVI.69.3.1612-1620.1995. 188757 .
• Keen NJ, Gait MJ, Karn J . Human immunodeficiency virus type-1 Tat is an integral component of the activated transcription-elongation complex. . Proc. Natl. Acad. Sci. U.S.A. . 93 . 6 . 2505–10 . 1996 . 8637904 . 10.1073/pnas.93.6.2505 . 39827 . 1996PNAS...93.2505K . free .
• Yang X, Herrmann CH, Rice AP . The human immunodeficiency virus Tat proteins specifically associate with TAK in vivo and require the carboxyl-terminal domain of RNA polymerase II for function. . J. Virol. . 70 . 7 . 4576–84 . 1996 . 8676484 . 10.1128/JVI.70.7.4576-4584.1996. 190394 .
• Agostini I, Navarro JM, Rey F, etal . The human immunodeficiency virus type 1 Vpr transactivator: cooperation with promoter-bound activator domains and binding to TFIIB. . J. Mol. Biol. . 261 . 5 . 599–606 . 1996 . 8800208 . 10.1006/jmbi.1996.0485 .
• Zhou Q, Sharp PA . Tat-SF1: cofactor for stimulation of transcriptional elongation by HIV-1 Tat. . Science . 274 . 5287 . 605–10 . 1996 . 8849451 . 10.1126/science.274.5287.605 . 1996Sci...274..605Z . 13266489 .
• Okamoto H, Sheline CT, Corden JL, etal . Trans-activation by human immunodeficiency virus Tat protein requires the C-terminal domain of RNA polymerase II. . Proc. Natl. Acad. Sci. U.S.A. . 93 . 21 . 11575–9 . 1996 . 8876177 . 10.1073/pnas.93.21.11575 . 38099 . 1996PNAS...9311575O . free .
• Chun RF, Jeang KT . Requirements for RNA polymerase II carboxyl-terminal domain for activated transcription of human retroviruses human T-cell lymphotropic virus I and HIV-1. . J. Biol. Chem. . 271 . 44 . 27888–94 . 1996 . 8910388 . 10.1074/jbc.271.44.27888 . free .
• Parada CA, Roeder RG . Enhanced processivity of RNA polymerase II triggered by Tat-induced phosphorylation of its carboxy-terminal domain. . Nature . 384 . 6607 . 375–8 . 1996 . 8934526 . 10.1038/384375a0 . 1996Natur.384..375P . 4278432 .
• García-Martínez LF, Ivanov D, Gaynor RB . Association of Tat with purified HIV-1 and HIV-2 transcription preinitiation complexes. . J. Biol. Chem. . 272 . 11 . 6951–8 . 1997 . 9054383 . 10.1074/jbc.272.11.6951 . free .
• Cujec TP, Cho H, Maldonado E, etal . The human immunodeficiency virus transactivator Tat interacts with the RNA polymerase II holoenzyme. . Mol. Cell. Biol. . 17 . 4 . 1817–23 . 1997 . 9121429 . 10.1128/mcb.17.4.1817. 232028 .
• García-Martínez LF, Mavankal G, Neveu JM, etal . Purification of a Tat-associated kinase reveals a TFIIH complex that modulates HIV-1 transcription. . EMBO J. . 16 . 10 . 2836–50 . 1997 . 9184228 . 10.1093/emboj/16.10.2836 . 1169892 .

Notes and References

1. Khazak V, Estojak J, Cho H, Majors J, Sonoda G, Testa JR, Golemis EA . Analysis of the interaction of the novel RNA polymerase II (pol II) subunit hsRPB4 with its partner hsRPB7 and with pol II . Mol Cell Biol . 18 . 4 . 1935–45 . May 1998 . 9528765 . 121423 . 10.1128/mcb.18.4.1935.
2. Web site: Entrez Gene: POLR2D polymerase (RNA) II (DNA directed) polypeptide D.