青岛华大研究院Guangyi Fan等研究人员合作发现，南极磷虾巨大的高重复基因组揭示其环境适应和群体演化。这一研究成果于2023年3月2日在线发表在国际学术期刊《细胞》上。
研究人员报道了一个48.01GB染色体水平的南极磷虾基因组，其巨大的基因组大小似乎是由基因间转座因子扩张造成的。它们的组装揭示了南极磷虾生物钟的分子结构，并揭示了与蜕皮和能量代谢相关的扩展基因家族，并为适应寒冷和高度季节性的南极环境提供了见解。来自南极大陆周围地理位置的种群水平基因组重新测序没有揭示出明确的种群结构，但强调了与环境变量相关的自然选择。磷虾数量每年急剧减少1000万，随后又在100万年前反弹，这与气候变化事件是一致的。这些发现揭示了南极磷虾适应南大洋的基因组基础，为未来的南极研究提供了宝贵的资源。
据悉，南极磷虾（Euphathemia superba）是地球上数量最多的野生动物，其巨大的生物量对南大洋生态系统至关重要。
附：英文原文
Title: The enormous repetitive Antarctic krill genome reveals environmental adaptations and population insights
Author: Changwei Shao, Shuai Sun, Kaiqiang Liu, Jiahao Wang, Shuo Li, Qun Liu, Bruce E. Deagle, Inge Seim, Alberto Biscontin, Qian Wang, Xin Liu, So Kawaguchi, Yalin Liu, Simon Jarman, Yue Wang, Hong-Yan Wang, Guodong Huang, Jiang Hu, Bo Feng, Cristiano De Pittà, Shanshan Liu, Rui Wang, Kailong Ma, Yiping Ying, Gabrielle Sales, Tao Sun, Xinliang Wang, Yaolei Zhang, Yunxia Zhao, Shanshan Pan, Xiancai Hao, Yang Wang, Jiakun Xu, Bowen Yue, Yanxu Sun, He Zhang, Mengyang Xu, Yuyan Liu, Xiaodong Jia, Jiancheng Zhu, Shufang Liu, Jue Ruan, Guojie Zhang, Huanming Yang, Xun Xu, Jun Wang, Xianyong Zhao, Bettina Meyer, Guangyi Fan
Issue&Volume: 2023-03-02
Abstract: Antarctic krill (Euphausia superba) is Earth’s most abundant wild animal, and its enormous biomass is vital to the Southern Ocean ecosystem. Here, we report a 48.01-Gb chromosome-level Antarctic krill genome, whose large genome size appears to have resulted from inter-genic transposable element expansions. Our assembly reveals the molecular architecture of the Antarctic krill circadian clock and uncovers expanded gene families associated with molting and energy metabolism, providing insights into adaptations to the cold and highly seasonal Antarctic environment. Population-level genome re-sequencing from four geographical sites around the Antarctic continent reveals no clear population structure but highlights natural selection associated with environmental variables. An apparent drastic reduction in krill population size 10 mya and a subsequent rebound 100 thousand years ago coincides with climate change events. Our findings uncover the genomic basis of Antarctic krill adaptations to the Southern Ocean and provide valuable resources for future Antarctic research.
DOI: 10.1016/j.cell.2023.02.005
Source: https://www.cell.com/cell/fulltext/S0092-8674(23)00107-1