Top3b

Symbol: Top3b
Name: Topoisomerase (DNA) III beta
Entrez gene ID: 21976
Ensembl gene ID: ENSMUSG00000022779
Species: Mouse (Taxid: 10090)

Functional description:
Releases the supercoiling and torsional tension of DNA introduced during the DNA replication and transcription by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-OH DNA strand. The free DNA strand than undergoes passage around the unbroken strand thus removing DNA supercoils. Finally, in the religation step, the DNA 3'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone (By similarity). Possesses negatively supercoiled DNA relaxing activity. [UniProt]

Observation:

Homozygous disruption of Top3b results in a normal development but a shorter lifespan (by approximately 70%) accompanied by lesions in multiple organs in C57BL/6 [11331780].

Yeast Top3 physically interacts with Sgs1 [7969174]. Human TOP3A interacts with BLM [10734115; 10728666] and both TOP3A and TOP3B interact with RECQ5 [10710432].



Interventions:
  • Top3b knockout -70%

  • Assays: Organismal Lifespan

    Classification:
  • Aging-Suppressor
  • Negative Aging-Suppressor


  • Aging Relevance Analysis/Source:
  • GenAge
  • GenDR

  • Homologs
  • TOP3B (9606)
  • TOP3B (9598)
  • TOP3B (9615)
  • TOP3B (9913)
  • Top3b (10090)
  • Top3b (10116)
  • TOP3B (9031)
  • LOC100329289 (7955)
  • Top3beta (7227)
  • Y48C3A.14 (6239)
  • AT2G32000 (3702)
  • Os09g0500600 (4530)



  • Edit \ Update (Admin) | Delete

    Comment on This Data Unit