作者
Kun Wang,Jun Wang,Chenglong Zhu,Liandong Yang,Yandong Ren,Jue Ruan,Guangyi Fan,Jiang Hu,Wenjie Xu,X. J. Bi,Y. H. Zhu,Yue Song,Huatao Chen,Tiantian Ma,Ruoping Zhao,Haifeng Jiang,Bin Zhang,Chenguang Feng,Yuan Yuan,Xiaoni Gan,Yongxin Li,H.R. Zeng,Qun Liu,Yaolei Zhang,Feng Shao,Shijie Hao,He Zhang,Xun Xu,Xin Liu,De-Peng Wang,Min Zhu,Guojie Zhang,Wenming Zhao,Qiang Qiu,Shunping He,Wen Wang
摘要
Summary Lungfishes are the closest extant relatives of tetrapods and preserve ancestral traits linked with the water-to-land transition. However, their huge genome sizes have hindered understanding of this key transition in evolution. Here, we report a 40-Gb chromosome-level assembly of the African lungfish (Protopterus annectens) genome, which is the largest genome assembly ever reported and has a contig and chromosome N50 of 1.60 Mb and 2.81 Gb, respectively. The large size of the lungfish genome is due mainly to retrotransposons. Genes with ultra-long length show similar expression levels to other genes, indicating that lungfishes have evolved high transcription efficacy to keep gene expression balanced. Together with transcriptome and experimental data, we identified potential genes and regulatory elements related to such terrestrial adaptation traits as pulmonary surfactant, anxiolytic ability, pentadactyl limbs, and pharyngeal remodeling. Our results provide insights and key resources for understanding the evolutionary pathway leading from fishes to humans.