A critical site in the cell surface receptor for ecotropic murine retroviruses required for amino acid transport but not for viral reception.
The cell surface receptor (ecoR) for ecotropic host-range murine retroviruses is a Na(+)-independent transporter for cationic amino acids that is distantly related to yeast transporters for arginine, histidine, and choline. All members of this transporter family contain a conserved glutamic acid that occurs in a hydrophobic presumptive transmembrane region of ecoR at position 107. To address the function of this site, we conservatively mutated ecoR by substituting aspartic acid at this position. The mutant protein was processed to cell surfaces where it bound the ecotropic virus envelope glycoprotein and functioned as a viral receptor, but it lacked amino acid transport activity. Functional transporter cycling is not required for viral reception by ecoR.
Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland 97201-3098.
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D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000737:chemistry* / Q000378:metabolism; D017931:DNA Primers / Q000737:chemistry; D008562:Membrane Glycoproteins; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011991:Receptors, Virus / Q000737:chemistry* / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
D000596:Amino Acids; D002352:Carrier Proteins; D017931:DNA Primers; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D011991:Receptors, Virus; C070506:ecotropic murine leukemia virus receptor