TOP2A

Topoisomerase (DNA) II alpha 170kDa
PDB rendering based on 1zxm.
Available structures PDB 1LWZ, 1ZXM, 1ZXN
Identifiers
Symbols	TOP2A; TOP2; TP2A
External IDs	OMIM: 126430 MGI: 98790 HomoloGene: 830 GeneCards: TOP2A Gene
EC number	5.99.1.3
Gene Ontology Molecular function • nucleotide binding • DNA binding • chromatin binding • sequence-specific DNA binding transcription factor activity • DNA topoisomerase (ATP-hydrolyzing) activity • protein kinase C binding • protein binding • ATP binding • protein C-terminus binding • DNA-dependent ATPase activity • drug binding • enzyme binding • protein homodimerization activity • histone deacetylase binding • ubiquitin binding • sequence-specific DNA binding • structure-specific DNA binding • protein heterodimerization activity Cellular component • nuclear chromosome • condensed chromosome • synaptonemal complex • nucleus • nucleoplasm • nucleolus • nucleolus • cytoplasm • centriole • DNA topoisomerase complex (ATP-hydrolyzing) • viral integration complex • protein complex Biological process • resolution of meiotic recombination intermediates • sister chromatid segregation • DNA replication • DNA-dependent DNA replication • DNA topological change • DNA ligation • DNA repair • mitotic recombination • response to DNA damage stimulus • chromosome segregation • aging • apoptotic chromosome condensation • embryonic cleavage • response to drug • positive regulation of apoptosis • positive regulation of viral genome replication • positive regulation of retroviral genome replication • positive regulation of transcription from RNA polymerase II promoter • phosphatidylinositol-mediated signaling • mitotic cell cycle G2/M transition decatenation checkpoint • response to parathyroid hormone stimulus Sources: Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	7153	21973
Ensembl	ENSG00000131747	ENSMUSG00000020914
UniProt	P11388	Q3TTG4
RefSeq (mRNA)	NM_001067.3	NM_011623.2
RefSeq (protein)	NP_001058.2	NP_035753.2
Location (UCSC)	Chr 17: 38.54 – 38.57 Mb	Chr 11: 98.85 – 98.89 Mb
PubMed search	[1]	[2]

DNA topoisomerase 2-alpha is an enzyme that in humans is encoded by the TOP2A gene.

This gene encodes a DNA topoisomerase, an enzyme that controls and alters the topologic states of DNA during transcription. This nuclear enzyme is involved in processes such as chromosome condensation, chromatid separation, and the relief of torsional stress that occurs during DNA transcription and replication. It catalyzes the transient breaking and rejoining of two strands of duplex DNA which allows the strands to pass through one another, thus altering the topology of DNA. Two forms of this enzyme exist as likely products of a gene duplication event. The gene encoding this form, alpha, is localized to chromosome 17 and the beta gene is localized to chromosome 3. The gene encoding this enzyme functions as the target for several anticancer agents and a variety of mutations in this gene have been associated with the development of drug resistance. Reduced activity of this enzyme may also play a role in ataxia-telangiectasia.

Interactions

TOP2A has been shown to interact with HDAC1, CDC5L, Small ubiquitin-related modifier 1 and P53.

Further reading

• Watt PM, Hickson ID (1994). "Structure and function of type II DNA topoisomerases.". Biochem. J. 303 (3): 681–95. PMC 1137600. PMID 7980433. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1137600. 
• Bronner C, Hopfner R, Mousli M (2002). "Transcriptional regulation of the human topoisomerase IIalpha gene.". Anticancer Res. 22 (2A): 605–12. PMID 12014628. 
• Järvinen TA, Liu ET (2004). "Topoisomerase IIalpha gene (TOP2A) amplification and deletion in cancer--more common than anticipated.". Cytopathology 14 (6): 309–13. doi:10.1046/j.0956-5507.2003.00105.x. PMID 14632727.