FSIP2

fibrous sheath interacting protein 2

Tier: Gold Standard Ciliary Genes

Ensembl:
ENSG00000188738
UniProt:
Q5CZC0
OMIM:
615796
Synonyms:
FLJ34780

Cilia effects upon perturbation of FSIP2

Loss-of-function effect:
Shorter (sperm flagella, MMAF)

Ciliogenesis screen results (3 screens)

  • Breslow et al. 2018 (CRISPR) [CRISPR]: No Significant Effect PMID:29459680
  • Roosing et al. 2015 (siRNA) [siRNA]: No effect PMID:26595381
  • Elliott et al. 2025 (CRISPRa) [CRISPRa]: Disassembly Trigger (casTLE Effect=-2.86) PMID:41160700

Subcellular localization

basal body, cilia

References: PMID:41005307, PMID:30137358

Functional category

  • Ciliary assembly/disassembly
  • Actin & cytoskeleton regulation
  • Reproduction & sperm
  • Cell migration & adhesion

Function

Major structural protein of the fibrous sheath (FS) shown to bind to AKAP4, required for FS assembly. Regulaties PKA anchoring to AKAP4. Involved in the control of sperm flagellum elasticity and signaling pathways that regulate sperm motility. Mutations in FSIP2 are a recurrent cause of multiple morphological abnormalities of the sperm flagella. All spermatozoa from patients FSIP2_3 and FSIP2_4 have shorter flagella than controls. (30137358)