id: Pfam:PF09431
pfam_id: PF09431
name: SPIN90/Ldb17, leucine-rich domain
short_name: SPIN90_LRD
seed_status: EX_DUF
characterization_status: UNSCORED
curation_status: SEEDED
source_url: https://www.ebi.ac.uk/interpro/api/entry/pfam/PF09431
counters:
  proteins: 3159
  matches: 3169
  proteomes: 2626
  taxa: 6971
  structures: 7
  alphafold_models: 2686
  domain_architectures: 55
provenance:
  snapshot_id: interpro-pfam-duf-2026-10-10
  path: data/worklists/interpro-pfam-duf-2026-10-10.json
  sha256: 17fb625876c9326ed284263a47bcd84e0d7844a31c040dc06cd2260c36f1c383
  generated_at: '2026-10-10T07:44:21.614711Z'
  source_url: https://www.ebi.ac.uk/interpro/api/entry/pfam/
interpro_id: InterPro:IPR018556
description: This is the conserved leucine-rich domain (LRD) within the C-terminal domain of SPIN90 (also
  known as NCK interacting protein with SH3 domain (NCKIPSD)) from animals, Ldb17 from budding yeasts
  and Dip1 from fission yeasts [[cite:PUB00098231]]. Ldb17 is involved in the regulation of endocytosis
  in yeast [[cite:PUB00054166]]. SPIN90 is an F-actin binding protein that regulates actin polymerization
  and endocytosis [[cite:PUB00085468]]. It associates with and activates the Arp2/3 complex, without requiring
  a preformed actin filament [[cite:PUB00054166],[cite:PUB00033588],[cite:PUB00054167]]. This LRD, within
  the C-terminal armadillo repeat (ARM) domain of SPIN90, is important for activation of Arp2/3 complex
  [[cite:PUB00098231]].