ISOLATION AND CHARACTERIZATION OF FATTY-ACID BINDING-PROTEINS FROM MAMMARY TISSUE OF LACTATING RATS
ISOLATION AND CHARACTERIZATION OF FATTY-ACID BINDING-PROTEINS FROM MAMMARY TISSUE OF LACTATING RATS
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DOI：
10.1042/bj2510919
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发表时间：
1988-05-01
影响因子：
4.1
通讯作者：
GRIGOR, MR
中科院分区：
文献类型：
--
作者：
JONES, PD;CARNE, A;GRIGOR, MR
从哺乳期大鼠的乳腺组织中分离出一种具有脂肪酸结合活性的蛋白质组分，分离过程包括DEAE-纤维素离子交换层析、热处理、CM-纤维素离子交换层析和最后的硫酸铵沉淀。纯化的组分在SDS/聚丙烯酰胺凝胶电泳上迁移为单一条带，表观分子量为14，400。然而，当在非解离条件下对该蛋白质级分进行分离时，观察到两种物质的比例为4：1。采用高效液相色谱法分离两种组分。两者都结合脂肪酸，似乎具有相似的氨基酸组成，但表现出不同的pI值为4.8和4.9。根据电泳迁移率和氨基酸组成，乳腺脂肪酸结合蛋白似乎与从大鼠心脏分离的脂肪酸结合蛋白非常相似。已对主要乳房形式（pI 4.9）进行了部分测序，所得氨基酸序列可与修订的大鼠心脏氨基酸序列的67个残基进行比对[Heuckeroth，Birkenmeier，Levin和Gordon（1987）J.Biol.Chem.262，9709-9717]。当使用抗心脏蛋白的抗血清进行检测时，两种乳腺物种也显示出对大鼠心脏脂肪酸结合蛋白的免疫化学特性。针对小乳腺形式（pI 4.8）产生的抗血清在非变性条件下特异性沉淀该形式，但两种形式都在变性后沉淀。定量免疫测定使用的抗（心脏脂肪酸结合蛋白）血清表明，在哺乳期增加，并进一步增加喂养高脂肪饮食后，乳腺细胞质中存在的脂肪酸结合蛋白的浓度。
A protein fraction with fatty acid binding activity has been isolated from mammary tissue from lactating rats by a process involving DEAE-cellulose ion-exchange chromatography, heat treatment, CM-cellulose ion-exchange chromatography and finally ammonium sulphate precipitation. The purified fraction migrated as a single band on SDS/polyacrylamide-gel electrophoresis with an apparent molecular mass of 14,400. However, when this protein fraction was electrophoresed under non-dissociating conditions, two species was observed in a 4:1 ratio. The two components were separated using h.p.l.c. Both bind fatty acids and appear to have similar amino acid compositions although exhibiting different pI values of 4.8 and 4.9. The mammary fatty acid binding proteins appear to be very similar to the fatty acid binding protein isolated from rat heart based on the electrophoretic mobilities and amino acid composition. The major mammary form (pI 4.9) has been partially sequenced and the amino acid sequences obtained can be aligned with 67 residues of the revised rat heart amino acid sequence [Heuckeroth, Birkenmeier, Levin and Gordon (1987) J. Biol. Chem. 262, 9709-9717]. Both mammary species also showed immunochemical identity to rat heart fatty acid binding protein when tested using an anti-serum raised against the heart protein. Anti-sera raised against the minor mammary form (pI 4.8) specifically precipitated this form under non-denaturing conditions but both forms after they had been denatured. Quantitative immunoassays using the anti-(heart fatty acid binding protein) serum showed that concentrations of the fatty acid binding proteins present in mammary cytosols increase during lactation and increase further after feeding a high-fat diet.