Glyceraldehyde-3-phosphate dehydrogenase is a major protein associated with the plasma membrane of retinal photoreceptor outer segments

• Published in: The Journal of biological chemistry Vol. 265; no. 22; pp. 13308 - 13313
• Main Authors: SHU-CHAN HSU, MOLDAY, R. S
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Biochemistry and Molecular Biology 05.08.1990
• Subjects: Amino Acid Sequence; Animals; Biological and medical sciences; Cattle; Cell Membrane - enzymology; Cell physiology; Chymotrypsin - pharmacology; Erythrocyte Membrane - enzymology; Fundamental and applied biological sciences. Psychology; Glyceraldehyde-3-Phosphate Dehydrogenases - genetics; Glyceraldehyde-3-Phosphate Dehydrogenases - isolation & purification; Glyceraldehyde-3-Phosphate Dehydrogenases - metabolism; Humans; Kinetics; Molecular and cellular biology; Molecular Sequence Data; Molecular Weight; Photoreceptor Cells - enzymology; photoreceptors; plasma membranes; Protein Binding; retina; Rod Cell Outer Segment - enzymology; Sequence Homology, Nucleic Acid; Trypsin - pharmacology; Vision, photoreception; Purification; Bovine; Enzyme; Rod; Retina; Vertebrata; Mammalia; Enzymatic activity; Affinity chromatography; Glyceraldehyde-phosphate dehydrogenase; Plasma membrane; Artiodactyla; Ungulata
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(19)38299-7

A major 38-kDa protein associated with bovine rod outer segment plasma membranes, but not disk membranes, has been identified as glyceraldehyde-3-phosphate dehydrogenase on the basis of its N-terminal sequence and specific enzyme activity. This enzyme was extracted from lysed rod outer segments or isolated rod outer segment plasma membrane with 0.15 M NaCl and purified to homogeneity by affinity chromatography on a NAD(+)-agarose column. A specific activity of 90-100 units/mg of protein is within the range of activity obtained for glyceraldehyde-3-phosphate dehydrogenase isolated from other mammalian cells. Enzyme activity measurements indicate that this enzyme makes up approximately 2% of the total rod outer segment protein and over 11% of the plasma membrane protein. Protease digestion and binding studies on purified rod outer segment plasma and disk membranes suggest that glyceraldehyde-3-phosphate dehydrogenase reversibly interacts with a protease-sensitive plasma membrane-specific protein of rod outer segments. The finding that glyceraldehyde-3-phosphate dehydrogenase is present in large quantities in rod outer segments suggests that at least some of the energy required for the synthesis of ATP and GTP for phototransduction and other processes of the outer segment is derived from glycolysis which takes place within this organelle.