SPTBN5

Cilia effects upon perturbation of SPTBN5

Cilia number / % ciliated:

Decreased cilia number

Loss-of-function effect:

Shorter cilia

Ciliogenesis screen results (2 screens)

• Breslow et al. 2018 (CRISPR) [CRISPR]: No Significant Effect PMID:29459680
• Roosing et al. 2015 (siRNA) [siRNA]: No effect PMID:26595381

Ciliopathy associations

• Nonsyndromic Tetralogy of Fallot

Subcellular localization

cilia

Functional category

• Ciliary assembly/disassembly

Function

Sptbn5 colocalized with both acetylated 伪-tubulin and 纬-tubulin along the entire cilia.Immunofluorescence examination of E13.5 OFTs revealed significantly reduced cilia number and shorter lengths in homozygous mice compared with wild-type littermates (P < 0.05)(PMID: 41071877). We first examined the subcellular localization of these ciliary genes in both mouse embryonic fibroblasts (MEFs) and E10.5 mouse OFTs. Immunofluorescence staining analysis revealed that Mlf1 and Pkhd1l1 colocalized with acetylated α-tubulin and specifically accumulated in cilia axonemes, Sptbn5 colocalized with both acetylated α-tubulin and γ-tubulin along the entire cilia, Ppef2 and Tekt3 were localized to basal bodies of cilia, and Agbl2 was located at the base of cilia and overlapped with Nek2, a marker of centriole (Fig. 5A and fig. S16). However, because of the polygenic genetic architecture and low penetrance of nonsyndromic TOF, it was impossible to construct mouse models for each candidate ciliary gene to verify its pathogenic role in TOF. We therefore selected six previously unidentified genes (namely AGBL2, MLF1, PKHD1L1, PPEF2, SPTBN5, and TEKT3) with recurrent mutations for mouse models construction and phenotype validation, both to illustrate the reliability of our screening strategy and to provide in vivo evidence supporting the contribution of ciliary gene variants to TOF pathogenesis. (41071877)