Downstream effector for Rab11 which regulates Rab11 intracellular membrane trafficking functions such as endocytic recycling, intracellular ciliogenesis and protein export (, ). ATK1-mediated phosphorylation of WDR44 induces binding to Rab11 which activates endocytic recycling of transferrin receptor back to the plasma membrane . When bound to Rab11, prevents the formation of the ciliogenic Rab11-Rabin8/RAB3IP-RAB11FIP3 complex, therefore inhibiting preciliary trafficking and ciliogenesis . Participates in neo-synthesized protein export by connecting the endoplasmic reticulum (ER) with the endosomal tubule via direct interactions with the integral ER proteins VAPA or VAPB and the endosomal protein GRAFs (GRAF1/ARHGAP26 or GRAF2/ARHGAP10), which facilitates the transfer of proteins such as E-cadherin, MPP14 and CFTR into a Rab8-Rab10-Rab11-dependent export route .
Subcellular locations: Cytoplasm, Cytosol, Cytoplasm, Perinuclear region, Endosome membrane, Golgi apparatus, Trans-Golgi network
Colocalized with RAB11A, RAB8A, RAB10 and MICAL1 on endosomal tubules . Colocalized with RAB11A along microtubules oriented toward lamellipodia.