College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen 518083, China.
Gigascience. 2017 Jul 1;6(7):1-13. doi: 10.1093/gigascience/gix039.
The blunt snout bream Megalobrama amblycephala is the economically most important cyprinid fish species. As an herbivore, it can be grown by eco-friendly and resource-conserving aquaculture. However, the large number of intermuscular bones in the trunk musculature is adverse to fish meat processing and consumption. As a first towards optimizing this aquatic livestock, we present a 1.116-Gb draft genome of M. amblycephala, with 779.54 Mb anchored on 24 linkage groups. Integrating spatiotemporal transcriptome analyses, we show that intermuscular bone is formed in the more basal teleosts by intramembranous ossification and may be involved in muscle contractibility and coordinating cellular events. Comparative analysis revealed that olfactory receptor genes, especially of the beta type, underwent an extensive expansion in herbivorous cyprinids, whereas the gene for the umami receptor T1R1 was specifically lost in M. amblycephala. The composition of gut microflora, which contributes to the herbivorous adaptation of M. amblycephala, was found to be similar to that of other herbivores. As a valuable resource for the improvement of M. amblycephala livestock, the draft genome sequence offers new insights into the development of intermuscular bone and herbivorous adaptation.
圆口铜鱼是一种经济上最重要的鲤科鱼类，是草食性鱼类，可以通过环保和资源节约型水产养殖进行养殖。然而，其躯干部肌肉中的大量肌间骨不利于鱼肉加工和食用。作为优化这种水产养殖动物的第一步，我们提供了一个 11.16 亿碱基对的圆口铜鱼基因组草图，其中 779.54 兆碱基对被锚定在 24 条连锁群上。通过时空转录组分析的整合，我们表明肌间骨是通过膜内成骨形成的，在更基础的硬骨鱼类中形成，可能与肌肉收缩性和协调细胞事件有关。比较分析表明，嗅觉受体基因，特别是β型，在草食性鲤科鱼类中经历了广泛的扩张，而鲜味受体 T1R1 的基因在圆口铜鱼中特异性丢失。对有助于圆口铜鱼草食性适应的肠道微生物群的组成进行了研究，结果发现其组成与其他草食动物相似。作为圆口铜鱼养殖改良的宝贵资源，该基因组草图为肌间骨的发育和草食性适应提供了新的见解。
