cimp1, a novel astacin family metalloproteinase gene from East African cichlids, is differentially expressed between species during growth
cimp1, a novel astacin family metalloproteinase gene from East African cichlids, is differentially expressed between species during growth
复制标题
DOI：
10.1093/molbev/msi159
复制
发表时间：
2005-08-01
影响因子：
10.7
通讯作者：
Okada, N
中科院分区：
文献类型：
--
作者：
Kijimoto, T;Watanabe, M;Okada, N
维多利亚湖慈鲷是爆炸性适应性辐射的极好例子。尽管维多利亚湖慈鲷被认为是在很短的时间内（大约14000年）出现的，但它们具有各种物种特异性的表型。区分每个物种的一个重要表型是下巴的形状，它已经分化以适应湖中存在的各种各样的营养栖息地。在这里，我们展示了一种新的方法，通过检测差异表达基因来研究慈鲷颌骨形态在遗传水平上的多样化。我们使用DNA芯片来比较亲缘关系密切的慈鲷之间的基因表达水平。分析结果表明，两种慈鲷幼虫中某些基因的表达存在差异。其中一个克隆体编码新的阿斯特林家族金属蛋白酶。通过实时定量逆转录-聚合酶链反应对分离基因cimpl的表达水平进行了更详细的分析。在发育过程中观察到两种单色慈鲷的纤毛蛋白表达有显著差异。通过原位杂交，我们发现该基因仅在头和鳃上皮中表达。生化分析表明，慈鲷金属蛋白酶1 （CiMPl）具有蛋白水解活性，这是所有阿斯塔星家族蛋白的共同特性。由于一些astacin家族蛋白参与动物的形态发生，CiMPl有望参与慈鲷的物种特异性头部形态发生。这是第一个证明可以使用DNA芯片识别慈鲷之间差异表达基因的研究。
Lake Victoria cichlid fishes are excellent examples of explosive adaptive radiation. Although Lake Victoria cichlids are believed to have arisen during a short period (similar to 14,000 years), they have various species-specific phenotypes. One important phenotype that distinguishes each species is the shape of the jaw, which has diverged to adapt to the wide variety of trophic habitats present in the lake. Here we demonstrate a new approach to investigate the diversification of cichlid jaw morphology at the genetic level by examining differentially expressed genes. We used a DNA chip to compare gene expression levels between closely related cichlid fishes. This analysis indicated that the expression of some genes differed in the larvae of two cichlid species. One such clone encodes anew astacin family metalloproteinase. The expression level of the isolated gene, named cimpl, was analyzed in more detail by real-time quantitative reverse transcription-polymerase chain reaction. A significant difference in cimpl expression was observed between two Haplochromis cichlid species during development. Using in situ hybridization, we found that this gene is expressed only in head and gill epithelia. Biochemical analysis showed that cichlid metalloprotemase l (CiMPl) has proteolytic activity, a common attribute of all astacin family proteins. Because some astacin family proteins contribute to morphogenesis in animals, CiMPl is expected to participate in species-specific head morphogenesis in cichlids. This is the first study to demonstrate that differentially expressed genes among cichlids can be identified using a DNA chip.