Protein SFI1 homolog (SFI1)

Protein SFI1 homolog (SFI1) is a conserved centrin-binding protein present in eukaryotes from yeast to humans[1][3][7]. In humans, SFI1 localizes at the distal end of centrioles where it forms a complex with centrin proteins and plays a critical role in centriole assembly, the recruitment and localization of centrin, and ciliogenesis[3]. Its depletion disrupts the formation and function of cilia, underscoring its structural importance. In yeast, SFI1 is essential for duplication of the spindle pole body (SPB), with repeated centrin-binding motifs facilitating its role as a molecular scaffold within centrosomes[1][7]. SFI1 is not an enzyme, receptor, or transporter, and there are no known drugs targeting it. Though some aliases listed—like "protein phosphatase 1, regulatory subunit 139" (PPP1R139) and "PISD"—are unrelated genes, SFI1 should be restricted to Protein SFI1 homolog, a centrin-binding protein located in centrosomal structures[6][7]. Its operational defects may contribute to cellular architecture problems but not to specific recognized diseases.

Other names

SFI1 centrin binding proteinKIAA0542hSFI1PISDPPP1R139protein phosphatase 1, regulatory subunit 139hSfi1pSfi1 homologspindle assembly associatedhomolog of yeast Sfi1

None known; not currently considered a therapeutic drug target.