Kinetics of the reaction of a myelin basic protein peptide with soluble IAu.
The kinetics of formation and dissociation of IAu-peptide complexes have been examined in the absence of detergent, using a glycosylphosphatidylinositol (GPI)-linked form of IAu. The GPI-linked form contains a lipid membrane anchor which can be specifically cleaved by phosphatidylinositol-specific phospholipase C to yield a water-soluble form of IAu. We find rapid binding of the myelin basic protein (MBP) peptide analogue Ac(1-14)A4C15 to IAu, as well as rapid dissociation of IAu-MBP peptide complexes at neutral pH in the absence of detergent. The reaction kinetics of the water-soluble and detergent-solubilized complexes are the same to within experiment error. In the presence of this MBP peptide, Ac(1-14)A4C15, cells transfected with native IAu as well as cells transfected with a GPI-linked form of IAu are functional in stimulating T-helper hybridoma cells.
Mason
K
K
Department of Chemistry, Stanford University, California 94305, USA.
Denney
D W
DW
McConnell
H M
HM
D000595:Amino Acid Sequence; D000818:Animals; D003902:Detergents / Q000494:pharmacology; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D000949:Histocompatibility Antigens Class II / Q000276:immunology / Q000378:metabolism*; D006825:Hybridomas; D007700:Kinetics; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D004676:Myelin Basic Protein / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012995:Solubility; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014162:Transfection
D003902:Detergents; D017261:Glycosylphosphatidylinositols; D000949:Histocompatibility Antigens Class II; D004676:Myelin Basic Protein; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase