Topological analysis of peripherin/rds and abnormal glycosylation of the pathogenic Pro216-->Leu mutation.
Peripherin/ rds is an integral membrane glycoprotein found in the rim regions of vertebrate photoreceptor cell discs. The protein is believed to be involved in both formation and maintenance of the characteristic flattened morphology of the outer segment discs and its essential nature is demonstrated by the wide range of retinal degenerative disorders in which the protein has an involvement. Little structural data has been determined for peripherin/ rds, but a topological model of the protein has been proposed. In this paper, we present the first direct evidence for the topology of the protein through the use of scanning glycosylation mutagenesis. Both the topological data and the observation that only the Asn(229) site is efficiently glycosylated in this in vitro transcription/translation system support the common hypotheses. Additionally, expression of the Pro(216)-->Leu mutant demonstrates an abnormal glycosylation pattern, which may explain the mechanism by which this mutation precipitates a retinal degenerative phenotype.
School of Biochemistry and Molecular Biology, University of Leeds, Mount Preston Street, Leeds LS2 9JT, U.K.
Jonathan D J
JD
Wrigley
Claire L
CL
Nevett
John B C
JB
Findlay
D000595:Amino Acid Sequence; D000818:Animals; D001216:Asparagine / Q000235:genetics; D006031:Glycosylation; D007381:Intermediate Filament Proteins / Q000235:genetics* / Q000378:metabolism*; D007930:Leucine / Q000235:genetics*; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism*; D064531:Peripherins; D017354:Point Mutation; D011392:Proline / Q000235:genetics*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012162:Retinal Degeneration / Q000235:genetics / Q000503:physiopathology
D007381:Intermediate Filament Proteins; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D064531:Peripherins; D011994:Recombinant Proteins; D001216:Asparagine; D011392:Proline; D007930:Leucine