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Subcellular localization

cilia, Nucleoli fibrillar center, Cytosol

Functional category

• Metabolism
• Motors (dynein/kinesin)
• Ciliary assembly/disassembly

Function

We establish interactions between DNAAF9 (human Shulin) and mammalian ODA subunits, IFT proteins and the ciliary small guanosine triphosphatase (GTPase) ARL3 using proteomics and in vitro reconstitutions. Mutagenesis combined with biochemical and structural studies reveal that DNAAF9 and Shulin preferentially bind active Arl3-GTP highlighting a cross-species conservation of this interaction. GTP-loaded Arl3 can access, bind and displace Shulin from the packaged ODA-Shulin complex. We propose that, once the inhibited ODA complex enters growing cilia, Arl3-GTP displaces Shulin (DNAAF9) and sequesters it away from ODAs, promoting activation of their motility specifically inside cilia(41023246).