Decelerated Genome Evolution in Modern Vertebrates Revealed by Analysis of Multiple Lancelet Genomes
ARTICLE Received 20 May 2014 | Accepted 18 Nov 2014 | Published 19 Dec 2014 DOI: 10.1038/ncomms6896 OPEN Decelerated genome evolution in modern vertebrates revealed by analysis of multiple lancelet genomes Shengfeng Huang1, Zelin Chen1, Xinyu Yan1, Ting Yu1, Guangrui Huang1, Qingyu Yan1, Pierre Antoine Pontarotti2, Hongchen Zhao1, Jie Li1, Ping Yang1, Ruihua Wang1, Rui Li1, Xin Tao1, Ting Deng1, Yiquan Wang3,4, Guang Li3,4, Qiujin Zhang5, Sisi Zhou1, Leiming You1, Shaochun Yuan1, Yonggui Fu1, Fenfang Wu1, Meiling Dong1, Shangwu Chen1 & Anlong Xu1,6 Vertebrates diverged from other chordates B500 Myr ago and experienced successful innovations and adaptations, but the genomic basis underlying vertebrate origins are not fully understood. Here we suggest, through comparison with multiple lancelet (amphioxus) genomes, that ancient vertebrates experienced high rates of protein evolution, genome rearrangement and domain shuffling and that these rates greatly slowed down after the divergence of jawed and jawless vertebrates. Compared with lancelets, modern vertebrates retain, at least relatively, less protein diversity, fewer nucleotide polymorphisms, domain combinations and conserved non-coding elements (CNE). Modern vertebrates also lost substantial transposable element (TE) diversity, whereas lancelets preserve high TE diversity that includes even the long-sought RAG transposon. Lancelets also exhibit rapid gene turnover, pervasive transcription, fastest exon shuffling in metazoans and substantial TE methylation not observed in other invertebrates. These new lancelet genome sequences provide new insights into the chordate ancestral state and the vertebrate evolution. 1 State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China. 2 Evolution Biologique et Mode´lisation UMR 7353 Aix Marseille Universite´/CNRS, 3 Place Victor Hugo, 13331 Marseille, France.
[Show full text]