Analysis of the fatty acid components in a perchloric acid-soluble protein.
We had previously found that a perchloric acid-soluble protein (PSP1) occurs in rat liver, and that this novel protein inhibits protein synthesis in a rabbit reticulocyte lysate system (T. Oka, H. Tsuji, C. Noda, K. Sakai, Y.-H. Hong, I. Suzuki, S. Muñoz, Y. Natori, J. Biol. Chem. 270 (1995) 30060-30067). In the present study, we analyzed lipid components bound to PSP1. Native PSP1 was purified from rat liver using Sephadex G-75, DE-52 cellulose and IgGPSP-affinity chromatography, and the lipid components were extracted. The components obtained from the purified PSP1 were shown to be free fatty acids by thin-layer chromatography. By GC-MS, six major fatty acids were identified as 14:0, 16:0, 18:0, 18:1, 18:2 and 20:4. 1 mol of PSP1 contained 1.26 mol of total fatty acid components. The fatty acid-binding assay of PSP1 showed that the Bmax was 1.25 mol fatty acid/mol PSP1 and the Kd value for palmitic acid was 6.03 microM. The concentration of PSP1 mRNA in rat liver increased 2.3-fold by the administration of peroxisome proliferator, bezafibrate. These findings show that PSP1 is a fatty acid-binding protein-like protein, which is involved in the intracellular metabolism of fatty acid and is quite different from the known fatty acid-binding proteins.
Sasagawa
T
T
Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Okayama 719-1197, Japan.
Oka
T
T
Tokumura
A
A
Nishimoto
Y
Y
Muñoz
S
S
Kuwahata
M
M
Okita
M
M
Tsuji
H
H
Natori
Y
Y
D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000032:analysis*; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D008099:Liver / Q000378:metabolism; D008297:Male; D018996:Myelin P2 Protein / Q000737:chemistry; D009206:Myocardium / Q000378:metabolism; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D011500:Protein Synthesis Inhibitors / Q000737:chemistry; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000737:chemistry; D012260:Ribonucleases
D002352:Carrier Proteins; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D006360:Heat-Shock Proteins; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D011500:Protein Synthesis Inhibitors; D012333:RNA, Messenger; D011994:Recombinant Proteins; C097211:Rida protein, rat; D012260:Ribonucleases; C490788:RIDA protein, human