The coxsackie B virus and adenovirus receptor resides in a distinct membrane microdomain.
The coxsackie B virus and adenovirus receptor (CAR) is a member of the immunoglobulin superfamily. In addition to activity as a viral receptor, it may play a role in cellular adhesion. We asked what determines the cell membrane microdomain of CAR. We found that CAR is localized to a novel lipid-rich microdomain similar to that of the low-density lipoprotein receptor (LDLR) but distinct from that of a CAR variant that exhibited traditional lipid raft localization via fusion to a glycosylphosphatidylinositol (GPI) tail. The cytoplasmic tail determines its membrane localization, since deletion of this domain resulted in mislocalization. Results indicate that CAR, CAR-LDLR, and LDLR reside in a novel lipid raft that is distinct from caveolin-1-containing caveolae and GPI-linked proteins. Residence in a lipid-rich domain provides a mechanism that allows CAR to interact with other cell adhesion proteins and yet function as an adenovirus receptor.
Ashbourne Excoffon
Katherine J D
KJ
Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
Moninger
Thomas
T
Zabner
Joseph
J
D000256:Adenoviridae / Q000378:metabolism / Q000472:pathogenicity*; D000818:Animals; D016466:CHO Cells; D019556:COS Cells; D002462:Cell Membrane / Q000378:metabolism*; D002966:Clathrin / Q000494:pharmacology; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein; D006224:Cricetinae; D004705:Endocytosis; D006801:Humans; D021962:Membrane Microdomains / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008854:Microscopy, Electron; D011973:Receptors, LDL / Q000378:metabolism; D011991:Receptors, Virus / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
C568771:CLMP protein, human; D002966:Clathrin; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein; D011973:Receptors, LDL; D011991:Receptors, Virus