Cloning of the αA-crystallin genes of a blind cave form and the epigean form of Astyanax fasciatus:: a comparative analysis of structure, expression and evolutionary conservation
Cloning of the αA-crystallin genes of a blind cave form and the epigean form of Astyanax fasciatus:: a comparative analysis of structure, expression and evolutionary conservation
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DOI：
10.1016/s0378-1119(98)00346-1
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发表时间：
1998-08-31
期刊：
影响因子：
3.5
通讯作者：
Schmale, H
中科院分区：
文献类型：
--
作者：
Behrens, M;Wilkens, H;Schmale, H
在本研究中，我们分析了α A-晶体蛋白基因的完整性和表达，编码的主要结构组成部分的透镜，在一个盲洞形式的硬骨鱼，Astyanax fasciatus。这是第一个从硬骨鱼中克隆的α A-晶体蛋白基因。这个洞穴形式的基因与其epigean同种和同源的远亲类群的序列比较，说明了保护的监管和编码区。虽然洞穴鱼的透镜中不产生晶状体蛋白，而且在不同发育阶段的原位杂交中也不能检测到该基因的mRNA，但洞穴鱼α A-晶状体蛋白的启动子区在功能上是完整的。洞穴型的α A-晶状体蛋白基因的推导氨基酸序列与其上位同种的α A-晶状体蛋白基因的推导氨基酸序列仅在一个位置上不同（139）。这是一个重要的，小的热休克蛋白相关区域，HCR 2。对A.与鸡同源物的比较揭示了晶状体特异性调控序列的高度保守性，并进一步证明了该基因的进化保守性。(C)1998 Elsevier Science B. V.保留所有权利。
In the present study we have analyzed the integrity and expression of the alpha A-crystallin gene, that codes for a major structural component of the lens, in a blind cave form of the teleostean fish, Astyanax fasciatus. This is the first alpha A-crystallin gene cloned from a teleostean fish. Sequence comparison of this cave-form gene with its epigean conspecific and with homologs of distantly related taxa has illustrated conservation of regulatory and coding regions. Although no crystallin proteins are produced in the lens of the cave form, and the mRNA of this gene could not be detected by in situ hybridization of different developmental stages, the promoter region of cave-fish alpha A-crystallin is functionally intact. The deduced amino-acid sequence of the alpha A-crystallin gene of the cave form differs from that of its epigean conspecific at only one position (139). This is within an important, small heat-shock protein-related region, HCR2. A comparison of the 5'-flanking regions of the A. fasciatus alpha A-crystallin gene with the chicken homolog revealed the high conservation of lens-specific regulatory sequences and further demonstrates the evolutionary conservation of this gene. (C) 1998 Elsevier Science B.V. All rights reserved.