*nlm.life
			PubMed Journals: Gene

  Source:		PMID: 12527193


    		Gene. 2003 Jan 2;302(1-2):21-9.
     
			Mammalian Crumbs3 is a small transmembrane
			protein linked to protein associated with
			Lin-7 (Pals1).

			Makarova O(1), Roh MH, Liu CJ, Laurinec
			S, Margolis B.

			Author Information
			(1) Howard Hughes Medical Institute,
			University of Michigan Medical School,
			4570 MSRB II, Box 0650, 1150 W. Medical
			Center Drive, Ann Arbor, MI 48109-0650,
			USA.

			Drosophila Crumbs is a transmembrane protein
			that plays an important role in epithelial
			cell polarity and photoreceptor development.
			Overexpression of Crumbs in Drosophila epithelia
			expands the apical surface and leads to
			disruption of cell polarity. Drosophila
			Crumbs also interacts with two other polarity
			genes, Stardust and Discs Lost. Recent work
			has identified a human orthologue of Drosophila
			Crumbs, known as CRB1, that is mutated in
			the eye disorders, retinitis pigmentosa
			and Leber congenital amaurosis. Our work
			has demonstrated that human CRB1 can form
			a complex with mammalian orthologues of
			Stardust and Discs Lost, known as protein
			associated with Lin-7 (Pals1) and Pals1
			associated tight junction (PATJ), respectively.
			In the current report we have cloned a full
			length cDNA for a human paralogue of CRB1
			called Crumbs3 (CRB3). In contrast to Drosophila
			Crumbs and CRB1, CRB3 has a very short extracellular
			domain but like these proteins it has a
			conserved intracellular domain that allows
			it to complex with Pals1 and PATJ. Mouse
			and human CRB3 have identical intracellular
			domains but divergent extracellular domains
			except for a conserved N-glycosylation site.
			CRB3 is localized to the apical surface
			and tight junctions but the conserved N
			linked glycosylation site does not appear
			to be necessary for CRB3 apical targeting.
			CRB3 is a specialized isoform of the Crumbs
			protein family that is expressed in epithelia
			and can tie the apical membrane to the tight
			junction.

			PMID: 12527193 [Indexed for MEDLINE]

     			                         Tweet       Print