Molecular cloning and characterization of Pals, proteins associated with mLin-7

Citation
E. Kamberov et al., Molecular cloning and characterization of Pals, proteins associated with mLin-7, J BIOL CHEM, 275(15), 2000, pp. 11425-11431
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
JOURNAL OF BIOLOGICAL CHEMISTRY
ISSN journal
0021-9258 → ACNP
Volume
275
Issue
15
Year of publication
2000
Pages
11425 - 11431
Database
ISI
SICI code
0021-9258(20000414)275:15<11425:MCACOP>2.0.ZU;2-H
Abstract
In Caenorhabditis elegans, three PDZ domain proteins, Lin-2, Lin-7, and Lin -10, are necessary for the proper targeting of the Let-23 growth factor rec eptor to the basolateral surface of epithelial cells. It has been demonstra ted that homologues of Lin-2, Lin-7, and Lin-10 form a heterotrimeric compl ex in mammalian brain. Using Far Western overlay assay, we have identified additional proteins that can bind to the amino terminus of mLin-7 and clone d the genes encoding these proteins using bacterial expression cloning. We call these proteins Pals, for proteins associated with Lin-7. These protein s, which include mammalian Lin-2, contain a conserved mLin-7 binding domain in addition to guanylate kinase, PDZ (postsynaptic density 95/discs large/ zona occludens-1), and Src homology 3 domains. Using site-directed mutagene sis, we have identified the conserved residues among these proteins crucial for mLin-7 binding. Two of these proteins, Pals1 and Pals2, are newly desc ribed. Pals1 consists of 675 amino acids and maps to mouse chromosome 12. P als2 was found to exist in two splice forms of 539 and 553 amino acids and maps to mouse chromosome 6. Like mLin-2, Pals1 and Pals2 localize to the la teral membrane in Madin-Darby canine kidney cells. Pals proteins represent a new subfamily of membrane-associated guanylate kinases that allow for mul tiple targeting complexes containing mLin-7.