The genome of an apodid holothuroid (Chiridota heheva) provides insights into its adaptation to a deep-sea reducing environment

作者：Long Zhang, Jian He, Jian He, Peipei Tan, Zhen Gong, Shiyu Qian, Yuanyuan Miao, Hanyu Zhang, Guangxian Tu, Qi Chen, Qiqi Zhong, Guanzhu Han, Jianguo He, Jianguo He, Muhua Wang · 发表于：Communications Biology · 年份：2022 · DOI：10.1038/s42003-022-03176-4 · 被引用次数：27 · 研究领域：Marine Biology and Ecology Research、Methane Hydrates and Related Phenomena、Protist diversity and phylogeny

Cold seeps and hydrothermal vents are deep-sea reducing environments that are characterized by lacking oxygen and photosynthesis-derived nutrients. Most animals acquire nutrition in cold seeps or hydrothermal vents by maintaining epi- or endosymbiotic relationship with chemoautotrophic microorganisms. Although several seep- and vent-dwelling animals hosting symbiotic microbes have been well-studied, the genomic basis of adaptation to deep-sea reducing environment in nonsymbiotic animals is still lacking. Here, we report a high-quality genome of Chiridota heheva Pawson & Vance, 2004, which thrives by extracting organic components from sediment detritus and suspended material, as a reference for nonsymbiotic animal's adaptation to deep-sea reducing environments. The expansion of the aerolysin-like protein family in C. heheva compared with other echinoderms might be involved in the disintegration of microbes during digestion. Moreover, several hypoxia-related genes (Pyruvate Kinase M2, PKM2; Phospholysine Phosphohistidine Inorganic Pyrophosphate Phosphatase, LHPP; Poly(A)-specific Ribonuclease Subunit PAN2, PAN2; and Ribosomal RNA Processing 9, RRP9) were subject to positive selection in the genome of C. heheva, which contributes to their adaptation to hypoxic environments.