Two novel brain proteins, CaBP33 and CaBP37, are calcium-dependent phospholipid- and membrane-binding proteins.
Two acidic Ca2(+)-binding proteins (CaBP33 and CaBP37) purified from bovine brain have been characterized in terms of immunological properties, heat-sensitivity, electrophoretic mobility, and Ca2(+)-dependent binding to negatively charged phospholipids and to brain membranes. They were induced to bind to membranes by homogenization of brain tissue in the presence of CaCl2. The membrane-bound CaBP33/CaBP37 mixture resisted extraction with detergents and was solubilized with high concentrations of EGTA/KCl. However, apparent Ca2(+)-independent binding of the two proteins to membranes seemed to occur as well. This latter fraction of membrane-bound CaBP33 and CaBP37 could be solubilized with Triton X-100, indicating that brain membranes normally contain the two proteins as intrinsic components.
Donato
R
R
Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy.
Giambanco
I
I
Pula
G
G
Bianchi
R
R
D000818:Animals; D001923:Brain Chemistry; D002118:Calcium / Q000494:pharmacology*; D002135:Calcium-Binding Proteins / Q000032:analysis / Q000276:immunology / Q000302:isolation & purification*; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism; D004533:Egtazic Acid / Q000494:pharmacology; D008970:Molecular Weight; D010743:Phospholipids / Q000378:metabolism*
D002135:Calcium-Binding Proteins; D010743:Phospholipids; D004533:Egtazic Acid; D002118:Calcium