title: Modification of plasma membrane protein cysteine residues by ADP-ribose in vivo.
abstract: Proteins can be post-translationally modified by ADP-ribose. Previously, two classes of ADP-ribosyl protein linkages have been detected in vivo which have chemical properties indistinguishable from ADP-ribosyl arginine and ADP-ribosyl glutamate or aspartate. Reported here is the detection of a third class of endogenous ADP-ribosyl protein linkage. This class is chemically indistinguishable from ADP-ribose linked to cysteine residues by a thioglycosidic bond. The distribution of ADP-ribosyl cysteine residues was studied in subcellular fractions of rat liver. Proteins modified on cysteine were detected only in the plasma membrane fraction. Pertussis toxin is known to disrupt signal transduction of ADP-ribosylation of cysteine residues of plasma membrane GTP binding proteins. The results described here raise the interesting possibility that the endogenous modification of plasma membrane protein cysteine residues may be involved in signal transduction.
authors.affiliation: Department of Biochemistry, Texas College of Osteopathic Medicine, University of North Texas, Forth Worth 76107.
authors.forename: M K
authors.initials: MK
authors.lastname: Jacobson
authors.forename: P T
authors.initials: PT
authors.lastname: Loflin
authors.forename: N
authors.initials: N
authors.lastname: Aboul-Ela
authors.forename: M
authors.initials: M
authors.lastname: Mingmuang
authors.forename: J
authors.initials: J
authors.lastname: Moss
authors.forename: E L
authors.initials: EL
authors.lastname: Jobson
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003545:Cysteine / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism; D008099:Liver / Q000648:ultrastructure; D008565:Membrane Proteins / Q000378:metabolism*; D037342:Pertussis Toxin; D011499:Protein Processing, Post-Translational; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D008565:Membrane Proteins; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D003545:Cysteine