HOOK2

Cilia effects upon perturbation of HOOK2

Cilia number / % ciliated:

Severe reduction/essentially none

Loss-of-function effect:

Ciliogenesis blocked

Ciliogenesis screen results (3 screens)

• Wheway et al. 2015 (siRNA) [siRNA]: No effect PMID:26167766
• Breslow et al. 2018 (CRISPR) [CRISPR]: No Significant Effect PMID:29459680
• Roosing et al. 2015 (siRNA) [siRNA]: No effect PMID:26595381

Subcellular localization

basal body, centrosome

Functional category

• Ciliary assembly/disassembly
• Trafficking (BBSome, small GTPases, vesicular transport, ATPases)
• Actin & cytoskeleton regulation
• Protein processing & maturation

Function

Hook2 localized to the centrosome through all phases of the cell cycle, its C-term domain directly binds to centriolin/CEP110, and it was demonstrated to contribute to the establishment and mainte nce of centrosomal structure and function (17140400). Hook2 depletion prevents ciliogenesis initiation, and this defect can be overcome by overexpression of murine Hook2 or Rab8a. Hook2 interacts with and regulates the expression of PCM1 that controls Rab8a recruitment to the primary cilium. The existence of a functio l complex containing Rab8a and Hook2 in association with PCM1, where Hook2 could play a role as an adaptor in the attachment of post-Golgi vesicles to the mother centriole during the formation of the ciliary sheath(21998199). Hook2 is involved in the morphogenesis of the primary cilium … Hook2 depletion disrupts ciliogenesis at a stage before the formation of the ciliary vesicle at the distal tip of the mother centriole. (21998199) Hook2 interacts with PCM1 in a complex that also contains Rab8a and regulates a limiting step required for further initiation of ciliogenesis after centriole maturation. (21998199) Hook2 binds aPKC-binding domain of PAR6α … depletion of Hook2 in ARPE-19 cells leads to loss of peri-centriolar material and blocks ciliogenesis. (27624926)

Model organism evidence