ARL13B

ARL13B is a member of the ADP-ribosylation factor-like family. The encoded protein is a small GTPase that contains both N-terminal and C-terminal guanine nucleotide-binding motifs. This protein is localized in the cilia and plays a role in cilia formation

Full Name

ADP-ribosylation factor-like 13B

Function

Cilium-specific protein required to control the microtubule-based, ciliary axoneme structure. May act by maintaining the association between IFT subcomplexes A and B. Binds GTP but is not able to hydrolyze it; the GTPase activity remains unclear. Required to pattern the neural tube. Involved in cerebral cortex development: required for the initial formation of a polarized radial glial scaffold, the first step in the construction of the cerebral cortex, by regulating ciliary signaling. Regulates the migration and placement of postmitotic interneurons in the developing cerebral cortex. May regulate endocytic recycling traffic; however, additional evidence is required to confirm these data.

Biological Process

Aggrephagy Source: Reactome
Cilium assembly Source: UniProtKB
Formation of radial glial scaffolds Source: UniProtKB
Interneuron migration from the subpallium to the cortex Source: UniProtKB
Neural tube patterning Source: UniProtKB
Non-motile cilium assembly Source: UniProtKB
Receptor localization to non-motile cilium Source: GO_Central
Smoothened signaling pathway Source: UniProtKB

Cellular Location

Cilium membrane; Cilium. Associates to the cilium membrane via palmitoylation. Localizes to proximal ciliary membranes, to an inversin-like subciliary membrane compartment, excluding the transition zone.

Involvement in disease

Joubert syndrome 8 (JBTS8): A disorder presenting with cerebellar ataxia, oculomotor apraxia, hypotonia, neonatal breathing abnormalities and psychomotor delay. Neuroradiologically, it is characterized by cerebellar vermian hypoplasia/aplasia, thickened and reoriented superior cerebellar peduncles, and an abnormally large interpeduncular fossa, giving the appearance of a molar tooth on transaxial slices (molar tooth sign). Additional variable features include retinal dystrophy and renal disease.

PTM

Sumoylation is required for PKD2 entry into cilium.