EHBP-1 functions with RAB-10 during endocytic recycling in Caenorhabditis elegans.
Caenorhabditis elegans RAB-10 functions in endocytic recycling in polarized cells, regulating basolateral cargo transport in the intestinal epithelia and postsynaptic cargo transport in interneurons. A similar role was found for mammalian Rab10 in MDCK cells, suggesting that a conserved mechanism regulates these related pathways in metazoans. In a yeast two-hybrid screen for binding partners of RAB-10 we identified EHBP-1, a calponin homology domain (CH) protein, whose mammalian homolog Ehbp1 was previously shown to function during endocytic transport of GLUT4 in adipocytes. In vivo we find that EHBP-1-GFP colocalizes with RFP-RAB-10 on endosomal structures of the intestine and interneurons and that ehbp-1 loss-of-function mutants share with rab-10 mutants specific endosome morphology and cargo localization defects. We also show that loss of EHBP-1 disrupts transport of membrane proteins to the plasma membrane of the nonpolarized germline cells, a defect that can be phenocopied by codepletion of RAB-10 and its closest paralog RAB-8. These results indicate that RAB-10 and EHBP-1 function together in many cell types and suggests that there are differences in the level of redundancy among Rab family members in polarized versus nonpolarized cells.
Shi
Anbing
A
Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854, USA.
Chen
Carlos Chih-Hsiung
CC
Banerjee
Riju
R
Glodowski
Doreen
D
Audhya
Anjon
A
Rongo
Christopher
C
Grant
Barth D
BD
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D004705:Endocytosis / Q000235:genetics / Q000502:physiology*; D011992:Endosomes / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D011485:Protein Binding; D021381:Protein Transport; D034622:RNA Interference; D018091:Receptors, AMPA / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
D029742:Caenorhabditis elegans Proteins; C555715:EHBP-1 protein, C elegans; D018091:Receptors, AMPA; D033921:Vesicular Transport Proteins; C096470:glr-1 protein, C elegans; D049452:Green Fluorescent Proteins; D000255:Adenosine Triphosphate; C510977:RAB-10 protein, C elegans; D020691:rab GTP-Binding Proteins