CSPP1

Cilia effects upon perturbation of CSPP1

Cilia number / % ciliated:

Decreased cilia number

Loss-of-function effect:

Shorter cilia

Overexpression effect:

longer cilia

Ciliogenesis screen results (2 screens)

• Wheway et al. 2015 (siRNA) [siRNA]: Ciliogenesis Defect (z=-2.90) PMID:26167766
• Breslow et al. 2018 (CRISPR) [CRISPR]: No Significant Effect PMID:29459680

Phenotypes

Mouse phenotype:

decreased circulating creatinine level, abnormal vocalization, decreased bone mineral content, abnormal coat/hair pigmentation

Human ciliopathy phenotype:

Joubert syndrome; Joubert syndrome 21; Meckel syndrome; Joubert syndrome with Jeune asphyxiating thoracic dystrophy

Ciliopathy associations

• Joubert Syndrome

Subcellular localization

basal body, centrosome, cilia, microtubules, transition zone

Functional category

• Ciliary assembly/disassembly
• Actin & cytoskeleton regulation
• Signaling (Hedgehog, GPCRs, ion channels)
• Transition zone

Function

CSPP proteins may be involved in cytoskeletal organization and for correct localisation of NPHP8 to the tip of the basal body that is forming the transition zone (20519441). Interacts with CEP104 at for the regulation of axoneme length and Hedgehog pathway stimulation (31412255). CSPP1 is required for localization of axonemal proteins, such as ARL13B and AC3, loss of CSPP1 is a cause of Joubert syndrome (24360808). The decreased cilium number and length in cell lines with CSPP1 mutations.