@article{HankeGogokhiaZhangFredericketal.2016, author = {Hanke-Gogokhia, Christin and Zhang, Houbin and Frederick, Jeanne M. and Baehr, Wolfgang}, title = {The Function of Arf-like Proteins ARL2 and ARL3 in Photoreceptors}, series = {Retinal Degenerative Diseases : Mechanisms and Experimental Therapy}, volume = {854}, journal = {Retinal Degenerative Diseases : Mechanisms and Experimental Therapy}, editor = {Rickman, CB and LaVail, MM and Anderson, RE and Grimm, C and Hollyfield, J and Ash, J}, publisher = {Springer International Publishing AG}, address = {Cham}, isbn = {978-3-319-17121-0; 978-3-319-17120-3}, issn = {0065-2598}, doi = {10.1007/978-3-319-17121-0_87}, pages = {655 -- 661}, year = {2016}, abstract = {Arf-like proteins (ARLs) are ubiquitously expressed small G proteins of the RAS superfamily. In photoreceptors, ARL2 and ARL3 participate in the trafficking of lipidated membrane-associated proteins and colocalize in the inner segment with UNC119A and PDE delta. UNC119A and PDE delta are acyl-and prenyl-binding proteins, respectively, involved in trafficking of acylated (transducin-alpha subunit, nephrocystin NPHP3) and prenylated proteins (GRK1, PDE6). Germline Arl3 knockout mice do not survive beyond postnatal day 21 and display ciliary defects in multiple organs (kidney, liver and pancreas) as well as retinal degeneration. Conditional knockouts will be necessary to delineate mechanisms of protein transport in retina disease.}, language = {en} } @article{HankeGogokhiaWuGerstneretal.2016, author = {Hanke-Gogokhia, Christin and Wu, Zhijian and Gerstner, Cecilia D. and Frederick, Jeanne M. and Zhang, Houbin and Baehr, Wolfgang}, title = {Arf-like Protein 3 (ARL3) Regulates Protein Trafficking and Ciliogenesis in Mouse Photoreceptors}, series = {The journal of biological chemistry}, volume = {291}, journal = {The journal of biological chemistry}, publisher = {American Society for Biochemistry and Molecular Biology}, address = {Bethesda}, issn = {0021-9258}, doi = {10.1074/jbc.M115.710954}, pages = {7142 -- 7155}, year = {2016}, abstract = {Arf-like protein 3 (ARL3) is a ubiquitous small GTPase expressed in ciliated cells of plants and animals. Germline deletion of Arl3 in mice causes multiorgan ciliopathy reminiscent of Bardet-Biedl or Joubert syndromes. As photoreceptors are elegantly compartmentalized and have cilia, we probed the function of ARL3 (ADP-ribosylation factor (Arf)-like 3 protein) by generating rod photoreceptor-specific (prefix (rod)) and retina-specific (prefix (ret)) Arl3 deletions. In predegenerate (rod)Arl3(-/-) mice, lipidated phototransduction proteins showed trafficking deficiencies, consistent with the role of ARL3 as a cargo displacement factor for lipid-binding proteins. By contrast, (ret)Arl3(-/-) rods and cones expressing Cre recombinase during embryonic development formed neither connecting cilia nor outer segments and degenerated rapidly. Absence of cilia infers participation of ARL3 in ciliogenesis and axoneme formation. Ciliogenesis was rescued, and degeneration was reversed in part by subretinal injection of adeno-associated virus particles expressing ARL3-EGFP. The conditional knock-out phenotypes permitted identification of two ARL3 functions, both in the GTP-bound form as follows: one as a regulator of intraflagellar transport participating in photoreceptor ciliogenesis and the other as a cargo displacement factor transporting lipidated protein to the outer segment. Surprisingly, a farnesylated inositol polyphosphate phosphatase only trafficked from the endoplasmic reticulum to the Golgi, thereby excluding it from a role in photoreceptor cilia physiology.}, language = {en} }