MNAT1 explained

CDK-activating kinase assembly factor MAT1 is an enzyme that in humans is encoded by the MNAT1 gene.^[1]

Function

Cyclin-dependent kinases (CDKs), which play an essential role in cell cycle control of eukaryotic cells, are phosphorylated and thus activated by the CDK-activating kinase (CAK). CAK is a multisubunit protein that includes CDK7 (MIM 601955), cyclin H (CCNH; MIM 601953), and MAT1. MAT1 (for 'ménage à trois-1') is involved in the assembly of the CAK complex.[supplied by OMIM]^[2]

Interactions

MNAT1 has been shown to interact with:

• Cyclin H,^[3]
• Cyclin-dependent kinase 7,^[4]
• Estrogen receptor alpha,
• MCM7,^[5]
• MTA1,^[6]
• P53,^[7] and
• POU2F1.^[8]

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 . free . 1998CBio....8.R447Y .
• Le Goff P, Montano MM, Schodin DJ, Katzenellenbogen BS . Phosphorylation of the human estrogen receptor. Identification of hormone-regulated sites and examination of their influence on transcriptional activity . J. Biol. Chem. . 269 . 6 . 4458–66 . 1994 . 10.1016/S0021-9258(17)41801-1 . 8308015 . free .
• Yee A, Nichols MA, Wu L, Hall FL, Kobayashi R, Xiong Y . Molecular cloning of CDK7-associated human MAT1, a cyclin-dependent kinase-activating kinase (CAK) assembly factor . Cancer Res. . 55 . 24 . 6058–62 . 1995 . 8521393 .
• Tassan JP, Jaquenoud M, Fry AM, Frutiger S, Hughes GJ, Nigg EA . In vitro assembly of a functional human CDK7-cyclin H complex requires MAT1, a novel 36 kDa RING finger protein . EMBO J. . 14 . 22 . 5608–17 . 1995 . 8521818 . 394676 . 10.1002/j.1460-2075.1995.tb00248.x.
• Blau J, Xiao H, McCracken S, O'Hare P, Greenblatt J, Bentley D . Three functional classes of transcriptional activation domain . Mol. Cell. Biol. . 16 . 5 . 2044–55 . 1996 . 8628270 . 231191 . 10.1128/MCB.16.5.2044.
• Reardon JT, Ge H, Gibbs E, Sancar A, Hurwitz J, Pan ZQ . Isolation and characterization of two human transcription factor IIH (TFIIH)-related complexes: ERCC2/CAK and TFIIH . Proc. Natl. Acad. Sci. U.S.A. . 93 . 13 . 6482–7 . 1996 . 8692841 . 39049 . 10.1073/pnas.93.13.6482 . 1996PNAS...93.6482R . free .
• Drapkin R, Le Roy G, Cho H, Akoulitchev S, Reinberg D . Human cyclin-dependent kinase-activating kinase exists in three distinct complexes . Proc. Natl. Acad. Sci. U.S.A. . 93 . 13 . 6488–93 . 1996 . 8692842 . 39050 . 10.1073/pnas.93.13.6488 . 1996PNAS...93.6488D . free .
• 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 .
• 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 .
• Richard Gaynor . 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 .
• Marinoni JC, Roy R, Vermeulen W, Miniou P, Lutz Y, Weeda G, Seroz T, Gomez DM, Hoeijmakers JH, Egly JM . Cloning and characterization of p52, the fifth subunit of the core of the transcription/DNA repair factor TFIIH . EMBO J. . 16 . 5 . 1093–102 . 1997 . 9118947 . 1169708 . 10.1093/emboj/16.5.1093 .
• Cujec TP, Cho H, Maldonado E, Meyer J, Reinberg D, Peterlin BM . The human immunodeficiency virus transactivator Tat interacts with the RNA polymerase II holoenzyme . Mol. Cell. Biol. . 17 . 4 . 1817–23 . 1997 . 9121429 . 232028 . 10.1128/mcb.17.4.1817.
• Rossignol M, Kolb-Cheynel I, Egly JM . Substrate specificity of the cdk-activating kinase (CAK) is altered upon association with TFIIH . EMBO J. . 16 . 7 . 1628–37 . 1997 . 9130708 . 1169767 . 10.1093/emboj/16.7.1628 .
• García-Martínez LF, Mavankal G, Neveu JM, Lane WS, Ivanov D, Gaynor RB . Purification of a Tat-associated kinase reveals a TFIIH complex that modulates HIV-1 transcription . EMBO J. . 16 . 10 . 2836–50 . 1997 . 9184228 . 1169892 . 10.1093/emboj/16.10.2836 .
• Nekhai S, Shukla RR, Kumar A . A human primary T-lymphocyte-derived human immunodeficiency virus type 1 Tat-associated kinase phosphorylates the C-terminal domain of RNA polymerase II and induces CAK activity . J. Virol. . 71 . 10 . 7436–41 . 1997 . 9311822 . 192089 . 10.1128/JVI.71.10.7436-7441.1997.
• Cujec TP, Okamoto H, Fujinaga K, Meyer J, Chamberlin H, Morgan DO, Peterlin BM . The HIV transactivator TAT binds to the CDK-activating kinase and activates the phosphorylation of the carboxy-terminal domain of RNA polymerase II . Genes Dev. . 11 . 20 . 2645–57 . 1997 . 9334327 . 316603 . 10.1101/gad.11.20.2645 .
• Inamoto S, Segil N, Pan ZQ, Kimura M, Roeder RG . The cyclin-dependent kinase-activating kinase (CAK) assembly factor, MAT1, targets and enhances CAK activity on the POU domains of octamer transcription factors . J. Biol. Chem. . 272 . 47 . 29852–8 . 1997 . 9368058 . 10.1074/jbc.272.47.29852 . free .
• Ko LJ, Shieh SY, Chen X, Jayaraman L, Tamai K, Taya Y, Prives C, Pan ZQ . p53 is phosphorylated by CDK7-cyclin H in a p36MAT1-dependent manner . Mol. Cell. Biol. . 17 . 12 . 7220–9 . 1997 . 9372954 . 232579 . 10.1128/mcb.17.12.7220.

Notes and References

1. Eki T, Okumura K, Abe M, Kagotani K, Taguchi H, Murakami Y, Pan ZQ, Hanaoka F . Mapping of the human genes encoding cyclin H (CCNH) and the CDK-activating kinase (CAK) assembly factor MAT1 (MNAT1) to chromosome bands 5q13.3-q14 and 14q23, respectively . Genomics . 47 . 1 . 115–20 . April 1998 . 9465303 . 10.1006/geno.1997.5053 .
2. Web site: Entrez Gene: MNAT1 menage a trois homolog 1, cyclin H assembly factor (Xenopus laevis).
3. Ewing RM, Chu P, Elisma F, Li H, Taylor P, Climie S, McBroom-Cerajewski L, Robinson MD, O'Connor L, Li M, Taylor R, Dharsee M, Ho Y, Heilbut A, Moore L, Zhang S, Ornatsky O, Bukhman YV, Ethier M, Sheng Y, Vasilescu J, Abu-Farha M, Lambert JP, Duewel HS, Stewart II, Kuehl B, Hogue K, Colwill K, Gladwish K, Muskat B, Kinach R, Adams SL, Moran MF, Morin GB, Topaloglou T, Figeys D . Large-scale mapping of human protein-protein interactions by mass spectrometry . Mol. Syst. Biol. . 3 . 89 . 2007 . 17353931 . 1847948 . 10.1038/msb4100134 .
4. Yee A, Nichols MA, Wu L, Hall FL, Kobayashi R, Xiong Y . Molecular cloning of CDK7-associated human MAT1, a cyclin-dependent kinase-activating kinase (CAK) assembly factor . Cancer Res. . 55 . 24 . 6058–62 . December 1995 . 8521393 .
5. Wang Y, Xu F, Hall FL . The MAT1 cyclin-dependent kinase-activating kinase (CAK) assembly/targeting factor interacts physically with the MCM7 DNA licensing factor . FEBS Lett. . 484 . 1 . 17–21 . October 2000 . 11056214 . 10.1016/s0014-5793(00)02117-7. 44625458 .
6. Talukder AH, Mishra SK, Mandal M, Balasenthil S, Mehta S, Sahin AA, Barnes CJ, Kumar R . MTA1 interacts with MAT1, a cyclin-dependent kinase-activating kinase complex ring finger factor, and regulates estrogen receptor transactivation functions . J. Biol. Chem. . 278 . 13 . 11676–85 . March 2003 . 12527756 . 10.1074/jbc.M209570200 . free .
7. Ko LJ, Shieh SY, Chen X, Jayaraman L, Tamai K, Taya Y, Prives C, Pan ZQ . p53 is phosphorylated by CDK7-cyclin H in a p36MAT1-dependent manner . Mol. Cell. Biol. . 17 . 12 . 7220–9 . December 1997 . 9372954 . 232579 . 10.1128/mcb.17.12.7220.
8. Inamoto S, Segil N, Pan ZQ, Kimura M, Roeder RG . The cyclin-dependent kinase-activating kinase (CAK) assembly factor, MAT1, targets and enhances CAK activity on the POU domains of octamer transcription factors . J. Biol. Chem. . 272 . 47 . 29852–8 . November 1997 . 9368058 . 10.1074/jbc.272.47.29852. free .