title: Mosaic Eyes is a novel component of the Crumbs complex and negatively regulates photoreceptor apical size.
abstract: Establishment of apical-basal cell polarity has emerged as an important process during development, and the Crumbs complex is a major component of this process in Drosophila. By comparison, little is known about the role of Crumbs (Crb) proteins in vertebrate development. We show that the FERM protein Mosaic Eyes (Moe) is a novel regulatory component of the Crumbs complex. Moe coimmunoprecipitates with Ome/Crb2a and Nok (Pals1) from adult eye and in vitro interaction experiments suggest these interactions are direct. Morpholino knockdown of ome/crb2a phenocopies the moe mutations. Moe and Crumbs proteins colocalize apically and this apical localization requires reciprocal protein function. By performing genetic mosaic analyses, we show that moe- rod photoreceptors have greatly expanded apical structures, suggesting that Moe is a negative regulator of Crumbs protein function in photoreceptors. We propose that Moe is a crucial regulator of Crumbs protein cell-surface abundance and localization in embryos.
authors.affiliation: Department of Biology, University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Ya-Chu
authors.initials: YC
authors.lastname: Hsu
authors.forename: John J
authors.initials: JJ
authors.lastname: Willoughby
authors.forename: Arne K
authors.initials: AK
authors.lastname: Christensen
authors.forename: Abbie M
authors.initials: AM
authors.lastname: Jensen
mesh_terms: D000818:Animals; D005136:Eye Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D006162:Guanylate Cyclase / Q000032:analysis / Q000378:metabolism; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D009024:Morphogenesis; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D011493:Protein Kinase C / Q000032:analysis / Q000378:metabolism; D017948:Retinal Rod Photoreceptor Cells / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics; D029961:Zebrafish Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D000099293:Protein Kinase C-lambda
chemical_list: D005136:Eye Proteins; D006162:Guanylate Cyclase; D007527:Isoenzymes; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011493:Protein Kinase C; D029961:Zebrafish Proteins; D000099293:Protein Kinase C-lambda; C517151:Crb1 protein, zebrafish; C513142:crb2b protein, zebrafish; C420034:epb41l5 protein, zebrafish; C501511:mpp5a protein, zebrafish