module: dmel_tdrd3_top3b_complex
title: Tdrd3-Top3beta topoisomerase complex in Drosophila melanogaster
label: Tdrd3-Top3beta complex
module_type: PROTEIN_COMPLEX
description: >-
  Topoisomerase 3-beta (TOP3B) is a type IA topoisomerase that can act on both
  DNA and RNA. It forms a conserved complex with the Tudor-domain protein TDRD3,
  which stimulates its activity, recruits it to messenger ribonucleoprotein
  complexes and links it to the fragile X protein FMRP. In Drosophila, Top3beta
  and Tdrd3 associate with each other and with Fmr1, and the complex has been
  implicated in synapse formation and in mRNA translation.
summary: >-
  Type IA topoisomerase Top3beta with its Tudor-domain partner Tdrd3, acting on
  RNA and DNA.
concepts:
  - {id: GO:0140225, label: DNA topoisomerase III-beta-TDRD3 complex}
notes: >-
  Modelled one part per subunit. Top3beta is given DNA topoisomerase activity;
  RNA topoisomerase activity has been reported for TOP3B including in flies but
  is not asserted here. Fmr1 is a partner, not a FlyBase member, and is not a
  part.
parts:
- id: top3beta_subunit
  label: Top3beta subunit
  role: catalytic type IA topoisomerase
  genes: [Top3beta]
  function: {id: 'GO:0003917', label: 'DNA topoisomerase type I (single strand cut, ATP-independent) activity'}
- id: tdrd3_subunit
  label: Tdrd3 subunit
  role: Tudor-domain scaffold and stimulatory subunit
  genes: [Tdrd3]
group: TDRD3-TOP3B