School of Marine Science, Ningbo University, Ningbo 315211, China.
National Engineering Research Laboratory of Marine Biotechnology and Engineering, Ningbo University, Ningbo 315211, China.
Int J Mol Sci. 2023 Jul 21;24(14):11769. doi: 10.3390/ijms241411769.
is important for commercial fishery catch species and is an emerging target for aquaculture production. Notably, has a bizarre morphology and lacks pelvic fins. However, the reason for the lack of pelvic fins remains unclear, ultimately leading to frequent upside-down floating of during breeding and marked consumption of physical energy. Some lineages, including whales, fugu, snakes, and seahorse, independently lost the pelvic appendages over evolutionary time. Do different taxa employ the same molecular genetic pathways when they independently evolve similar developmental morphologies? Through analysis of the gene responsible for appendage localization, Hoxd9, it was discovered that the Hox domain was absent in the gene of , and the gene lacked the Hox9 activation region, a feature not observed in the gene of other fish species. Interestingly, those distinctive characteristics are not observed in the gene of other fish species. To determine the association between the gene characteristics and the pelvic fin deletion in , the full-length cDNA of the gene was cloned, and morphological observations of the species' juveniles were performed using stereomicroscopy and scanning electron microscopy. Thereafter, the tissue localization of Hoxd9a in the species was analyzed at the gene and protein levels. Based on the results, deletion of the Hoxd9a structural domain possibly leads to disruptions in the protein translation and the pelvic fin localization in during its early ontogenetic developmental stage, resulting in the absence of pelvic fins.
对于商业渔业捕捞物种来说，是非常重要的，也是水产养殖生产的新兴目标。值得注意的是，没有偶鳍，具有奇异的形态。然而，缺乏偶鳍的原因尚不清楚，这最终导致在繁殖期间经常出现倒置漂浮，大量消耗体力。包括鲸鱼、河豚、蛇和海马在内的一些谱系在进化过程中独立失去了附肢。当不同的分类单元独立进化出相似的发育形态时，它们是否采用相同的分子遗传途径？通过分析负责附肢定位的基因 Hoxd9，发现基因中的 Hox 结构域缺失，基因缺乏 Hox9 激活区，这在其他鱼类的基因中没有观察到。有趣的是，在其他鱼类的基因中没有观察到这些独特的特征。为了确定基因特征与缺失之间的关联，克隆了基因的全长 cDNA，并通过立体显微镜和扫描电子显微镜对该物种的幼鱼进行了形态观察。然后，在基因和蛋白质水平上分析了 Hoxd9a 在该物种中的组织定位。基于这些结果，结构域的缺失可能导致在其早期个体发育阶段，蛋白质翻译和偶鳍定位受到破坏，从而导致缺乏偶鳍。
