[Topoisomerase II catalyzes relaxation of supercoiled DNA molecules, catenation, decatenation, knotting, and unknotting of circular DNA. The topoisomerase II reaction appears to involve crossing-over of two DNA segments. Human cells contain two topoisomerase II isozymes: alpha and beta from distinct genes. DNA topoisomerase II alpha is associated with the Pol II holoenzyme and is required for chromatin-dependent co-activation. Transcription results in superhelical tension; topoisomerase II relaxation activity is essential for productive RNA synthesis on nucleosomal DNA. (from OMIM 126430 and NCI) ( NCI )]
UMLS (CSP) C0012863 - Amino Acid, Peptide, or Protein
- Enzyme
home 
Armenian-English 
top