POLRMT explained
DNA-directed RNA polymerase, mitochondrial is an enzyme that in humans is encoded by the POLRMT gene.[1] [2]
Function
This gene encodes a mitochondrial DNA-directed RNA polymerase. The gene product is responsible for mitochondrial gene expression as well as for providing RNA primers for initiation of replication of the mitochondrial genome. Although this polypeptide has the same function as the three nuclear DNA-directed RNA polymerases, it is more closely related to RNA polymerases of bacteriophage (including T7 RNA polymerase), mitochondrial polymerases of lower eukaryotes as well as chloroplastic RpoT polymerases.[2]
Structure
The structure of the enzyme has been solved. It exhibits an overall structure similar to that of phage RNAP, but the initiation mechanism is different in that it requires initiation factors TFAM (only in mammals) and TFB2M.[3] Elongation requires the elongation factor TEFM.[4] The exact termination process is less understood, but MTERF1 is thought to play a role.[5]
Further reading
- Maruyama K, Sugano S . Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides. . Gene . 138 . 1–2 . 171–4 . 1994 . 8125298 . 10.1016/0378-1119(94)90802-8 .
- Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, etal . Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library . Gene . 200 . 1–2 . 149–56 . 1997 . 9373149 . 10.1016/S0378-1119(97)00411-3 .
- Maria Falkenberg . Falkenberg M, Gaspari M, Rantanen A, etal . Mitochondrial transcription factors B1 and B2 activate transcription of human mtDNA . Nat. Genet. . 31 . 3 . 289–94 . 2002 . 12068295 . 10.1038/ng909 . 11164308 .
- 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 .
- McCulloch V, Shadel GS . Human mitochondrial transcription factor B1 interacts with the C-terminal activation region of h-mtTFA and stimulates transcription independently of its RNA methyltransferase activity . Mol. Cell. Biol. . 23 . 16 . 5816–24 . 2003 . 12897151 . 10.1128/MCB.23.16.5816-5824.2003 . 166325 .
- Grimwood J, Gordon LA, Olsen A, etal . The DNA sequence and biology of human chromosome 19 . Nature . 428 . 6982 . 529–35 . 2004 . 15057824 . 10.1038/nature02399 . 2004Natur.428..529G . free .
- Graziewicz MA, Longley MJ, Bienstock RJ, etal . . Nat. Struct. Mol. Biol. . 11 . 8 . 770–6 . 2004 . 15258572 . 10.1038/nsmb805 . 12460199 .
- Gaspari M, Falkenberg M, Larsson NG, Gustafsson CM . The mitochondrial RNA polymerase contributes critically to promoter specificity in mammalian cells . EMBO J. . 23 . 23 . 4606–14 . 2005 . 15526033 . 10.1038/sj.emboj.7600465 . 533051 .
- Kravchenko JE, Rogozin IB, Koonin EV, Chumakov PM . Transcription of mammalian messenger RNAs by a nuclear RNA polymerase of mitochondrial origin . Nature . 436 . 7051 . 735–9 . 2005 . 16079853 . 10.1038/nature03848 . 1352165 . 2005Natur.436..735K .
- Wang Z, Cotney J, Shadel GS . Human mitochondrial ribosomal protein MRPL12 interacts directly with mitochondrial RNA polymerase to modulate mitochondrial gene expression . J. Biol. Chem. . 282 . 17 . 12610–8 . 2007 . 17337445 . 10.1074/jbc.M700461200 . 2606046 . free .
Notes and References
- Tiranti V, Savoia A, Forti F, D'Apolito MF, Centra M, Rocchi M, Zeviani M . Identification of the gene encoding the human mitochondrial RNA polymerase (h-mtRPOL) by cyberscreening of the Expressed Sequence Tags database . Hum Mol Genet . 6 . 4 . 615–25 . Jul 1997 . 9097968 . 10.1093/hmg/6.4.615 . free .
- Web site: Entrez Gene: POLRMT polymerase (RNA) mitochondrial (DNA directed).
- Hillen . HS . Morozov . YI . Sarfallah . A . Temiakov . D . Cramer . P . Structural Basis of Mitochondrial Transcription Initiation. . Cell . 16 November 2017 . 171 . 5 . 1072–1081.e10 . 10.1016/j.cell.2017.10.036 . 29149603. 6590061 .
- Hillen . Hauke S. . Parshin . Andrey V. . Agaronyan . Karen . Morozov . Yaroslav I. . Graber . James J. . Chernev . Aleksandar . Schwinghammer . Kathrin . Urlaub . Henning . Anikin . Michael . Cramer . Patrick . Temiakov . Dmitry . Mechanism of Transcription Anti-termination in Human Mitochondria . Cell . November 2017 . 171 . 5 . 1082–1093.e13 . 10.1016/j.cell.2017.09.035 . 29033127 . 5798601.
- D'Souza . AR . Minczuk . M . Mitochondrial transcription and translation: overview. . Essays in Biochemistry . 20 July 2018 . 62 . 3 . 309–320 . 10.1042/EBC20170102 . 30030363. 6056719 .