Jiang Yan-Zhi, Li Xue-Wei
College of Animal Science and Technology, Sichuan Agricultural University, Ya'an 625014, China.
Yi Chuan Xue Bao. 2006 Feb;33(2):125-32. doi: 10.1016/S0379-4172(06)60031-0.
The intestinal fatty acid-binding protein (I-FABP) shows binding specificity for long-chain fatty acids and is proposed to be involved in the uptake of dietary fatty acids and their intracellular transport. In this study, the full-length cDNA of I-FABP was cloned from pig intestine by homology cloning approach combined with 3' and 5' RACE. Sequence analysis and bioinformatics study showed that this cDNA contained 614 nucleotides, with a 399 bp open reading frame (ORF) flanked by a 43 bp 5' UTR and a 172 bp 3' UTR. The encoded 132 amino acids of pig I-FABP with a molecular weight of approximately 15 kDa shared a high sequence identity of 68%-85% with those of other species. In addition, the phylogenetical analysis also indicated that the pig I-FABP was in the same branch with those of other species. The tissue-specific expression of pig I-FABP was measured by Northern hybridization and semi-quantitative RT-PCR. The results demonstrated that pig I-FABP mRNA was extensively present in various tissues, but I-FABP transcript of approximately 620 bp was more abundant in intestine than in other tissues.
肠脂肪酸结合蛋白（I-FABP）对长链脂肪酸具有结合特异性，被认为参与膳食脂肪酸的摄取及其细胞内运输。在本研究中，采用同源克隆方法结合3'和5' RACE从猪肠道中克隆了I-FABP的全长cDNA。序列分析和生物信息学研究表明，该cDNA包含614个核苷酸，具有一个399 bp的开放阅读框（ORF），两侧分别是43 bp的5'非翻译区（UTR）和172 bp的3' UTR。猪I-FABP编码的132个氨基酸，分子量约为15 kDa，与其他物种的氨基酸序列具有68%-85%的高度同一性。此外，系统发育分析还表明，猪I-FABP与其他物种的I-FABP处于同一分支。通过Northern杂交和半定量RT-PCR检测了猪I-FABP的组织特异性表达。结果表明，猪I-FABP mRNA广泛存在于各种组织中，但约620 bp的I-FABP转录本在肠道中比在其他组织中更丰富。
