TOP3B explained

DNA topoisomerase 3-beta-1 is an enzyme that in humans is encoded by the TOP3B gene.^{[1] [2] [3]}

This gene encodes a DNA topoisomerase, an enzyme that controls and alters the topologic states of DNA during transcription. This enzyme catalyzes the transient breaking and rejoining of a single strand of DNA which allows the strands to pass through one another, thus relaxing the supercoils and altering the topology of DNA. The enzyme interacts with DNA helicase SGS1 and plays a role in DNA recombination, cellular aging and maintenance of genome stability. Alternative splicing of the C-terminus of this gene results in three transcript variants which have distinct tissue specificity; however, not all variants have been fully described.

Further reading

• Andersson B, Wentland MA, Ricafrente JY, etal . A "double adaptor" method for improved shotgun library construction . Anal. Biochem. . 236 . 1 . 107–13 . 1996 . 8619474 . 10.1006/abio.1996.0138 .
• Yu W, Andersson B, Worley KC, etal . Large-scale concatenation cDNA sequencing . Genome Res. . 7 . 4 . 353–8 . 1997 . 9110174 . 10.1101/gr.7.4.353. 139146 .
• Seki T, Seki M, Onodera R, etal . Cloning of cDNA encoding a novel mouse DNA topoisomerase III (Topo IIIbeta) possessing negatively supercoiled DNA relaxing activity, whose message is highly expressed in the testis . J. Biol. Chem. . 273 . 44 . 28553–6 . 1998 . 9786843 . 10.1074/jbc.273.44.28553 . free .
• Ng SW, Liu Y, Hasselblatt KT, etal . A new human topoisomerase III that interacts with SGS1 protein . Nucleic Acids Res. . 27 . 4 . 993–1000 . 1999 . 9927731 . 10.1093/nar/27.4.993 . 148278 .
• Shimamoto A, Nishikawa K, Kitao S, Furuichi Y . Human RecQ5beta, a large isomer of RecQ5 DNA helicase, localizes in the nucleoplasm and interacts with topoisomerases 3alpha and 3beta . Nucleic Acids Res. . 28 . 7 . 1647–55 . 2000 . 10710432 . 10.1093/nar/28.7.1647 . 102787 .
• Kobayashi M, Hanai R . M phase-specific association of human topoisomerase IIIbeta with chromosomes . Biochem. Biophys. Res. Commun. . 287 . 1 . 282–7 . 2001 . 11549288 . 10.1006/bbrc.2001.5580 .
• 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 .
• 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 .
• Lehner B, Sanderson CM . A protein interaction framework for human mRNA degradation . Genome Res. . 14 . 7 . 1315–23 . 2004 . 15231747 . 10.1101/gr.2122004 . 442147 .
• Cho YH, Park JY, Han SY, Chung IK . Identification of the functional elements in the promoter region of human DNA topoisomerase IIIbeta gene . Biochim. Biophys. Acta . 1679 . 3 . 272–8 . 2004 . 15358519 . 10.1016/j.bbaexp.2004.08.001 .
• Collins JE, Wright CL, Edwards CA, etal . A genome annotation-driven approach to cloning the human ORFeome . Genome Biol. . 5 . 10 . R84 . 2005 . 15461802 . 10.1186/gb-2004-5-10-r84 . 545604 . 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 .
• Rual JF, Venkatesan K, Hao T, etal . Towards a proteome-scale map of the human protein-protein interaction network . Nature . 437 . 7062 . 1173–8 . 2005 . 16189514 . 10.1038/nature04209 . 2005Natur.437.1173R . 4427026 .

Notes and References

1. Tang D, Kidd VJ . Cleavage of DFF-45/ICAD by multiple caspases is essential for its function during apoptosis . J Biol Chem . 273 . 44 . 28549–52 . Dec 1998 . 9786842 . 10.1074/jbc.273.44.28549 . free .
2. Kawasaki K, Minoshima S, Nakato E, Shibuya K, Shintani A, Schmeits JL, Wang J, Shimizu N . One-megabase sequence analysis of the human immunoglobulin lambda gene locus . Genome Res . 7 . 3 . 250–61 . May 1997 . 9074928 . 10.1101/gr.7.3.250 . free .
3. Web site: Entrez Gene: TOP3B topoisomerase (DNA) III beta.