Alternative splicing in lecithin:cholesterol acyltransferase mRNA: an evolutionary paradigm in humans and great apes.
Alternative splicing in lecithin:cholesterol acyltransferase mRNA: an evolutionary paradigm in humans and great apes.
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卵磷脂：胆固醇酰基转移酶 mRNA 中的选择性剪接：人类和类人猿的进化范例。
DOI：
10.1016/s0378-1119(97)00022-x
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发表时间：
1997
期刊：
影响因子：
3.5
通讯作者：
Zeller,K
中科院分区：
文献类型：
--
作者：
Miller,M;Zeller,K
卵磷脂：胆固醇酰基转移酶(LCAT)是一种影响胆固醇反向转运的重要酶，在肝脏和培养的成纤维细胞中都有表达。对LCAT基因克隆的测序结果表明，两种mRNA产物共存。除了正常的转录本外，我们还发现了一个由Alu盒在外显子5和6的交界处剪接介导插入95的替代信息。在人类中，替代转录本代表了培养的成纤维细胞和肝脏中完整LCAT信息的5-20%。它存在于人类和类人猿中，但不存在于较小的类人猿(长臂猿、猿猴)或低级灵长类动物(如东半球或西半球的猴子)。对几种灵长类动物的LCAT基因内含子5进行测序，发现长臂猿Alu重复序列中剪接供体识别位点的G→A转换，以及东半球恒河猴95位序列最后一位的G→A被Alu替换。这两个替换都与其他基因的外显子跳过有关。这些结果表明LCAT mRNA的选择性剪接在灵长类动物中是不同的，并提示Alu元件在蛋白质进化多样性中的潜在作用
Lecithin: cholesterol acyltransferase (LCAT), an important enzyme affecting reverse cholesterol transport, is expressed in liver and cultured fibroblasts. Sequencing of LCAT cDNA clones demonstrated the coexistence of two mRNA products. In addition to the normal transcript, we identified an alternate message with a splice-mediated insertion of a 95 by Alu cassette at the junction of exons 5 and 6. In humans, the alternate transcript represents 5–20% of the complete LCAT message in cultured fibroblasts and liver. It is present in humans and the great apes but not in lesser apes (gibbon, siamang) or lower-order primates (e.g., old or new world monkeys). Sequencing of intron 5 of the LCAT locus in several primates revealed a G→A transition at the splice donor recognition site in the Alu repeat of the gibbon and a G→A substitution in the last position of the 95 by Alu sequence of the rhesus monkey, an old world monkey. Both substitutions have been associated with exon skipping in other genes. These results demonstrate that alternative splicing of LCAT mRNA is variant among primates and suggest a potential role of Alu elements in the evolutionary diversity of proteins