Isolation and partial characterization of a fatty acid binding protein in rat liver plasma membranes.
Isolation and partial characterization of a fatty acid binding protein in rat liver plasma membranes.
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DOI：
10.1073/pnas.82.1.4
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发表时间：
1985
影响因子：
11.1
通讯作者：
W. Stremmel;G. Strohmeyer;F. Borchard;S. Kochwa;P. Berk
中科院分区：
文献类型：
--
作者：
W. Stremmel;G. Strohmeyer;F. Borchard;S. Kochwa;P. Berk
当[14C]油酸-牛血清白蛋白复合体与大鼠肝细胞质膜(LPM)体外孵育时，观察到油酸与膜的特异性饱和结合。最大热敏(即特异性)结合量为3.2nmol/mg膜蛋白。利用Triton X-100溶解的LPM的油酸-琼脂糖亲和层析分离出与油酸具有高亲和力的单一40 kDa蛋白。在凝胶过滤中，蛋白质与各种脂肪酸共迁移，但不与[14C]胆红素、[35S]磺基溴邻苯二甲酸、[14C]牛磺胆酸盐、[14C]磷脂酰胆碱或[14C]油酸胆固醇共迁移。该膜脂肪酸结合蛋白的兔抗体与该抗原呈单一沉淀线，但与浓缩胞浆蛋白、LPM胆红素/磺基溴化邻苯二甲酸结合蛋白、大鼠白蛋白或其他大鼠血浆蛋白无反应。该抗体选择性地抑制[14C]油酸盐与LPM的热敏结合。免疫荧光研究将该抗原定位于肝细胞质膜以及其他主要的脂肪酸转运部位。这些数据与该蛋白可能在肝细胞摄取脂肪酸机制中作为受体的假设是一致的。
When [14C]oleate-bovine serum albumin complexes were incubated in vitro with rat liver plasma membranes (LPM), specific, saturable binding of oleate to the membranes was observed. Maximal heat-sensitive (i.e., specific) binding was 3.2 nmol/mg of membrane protein. Oleate-agarose affinity chromatography of Triton X-100-solubilized LPM was used to isolate a single 40-kDa protein with high affinity for oleate. On gel filtration, the protein comigrated with various fatty acids but not with [14C]bilirubin, [35S]sulfobromophthalein, [14C]taurocholate, [14C]phosphatidylcholine, or [14C]cholesteryloleate. A rabbit antibody to this membrane fatty acid-binding protein gave a single precipitin line with the antigen but no reactivity with concentrated cytosolic proteins, LPM bilirubin/sulfobromophthalein-binding protein, or rat albumin or other rat plasma proteins. The antibody selectively inhibited heat-sensitive binding of [14C]oleate to LPM. Immunofluorescence studies localized the antigen in liver-cell plasma membranes as well as in other major sites of fatty acid transport. These data are compatible with the hypothesis that this protein may act as a receptor in a hepatocellular uptake mechanism for fatty acids.