High hydrostatic pressure,low temperature,and scarce food supply are the major factors that limit the survival of vertebrates in extreme deep-sea environments.Here,we constructed a high-quality genome of the deep-sea ...High hydrostatic pressure,low temperature,and scarce food supply are the major factors that limit the survival of vertebrates in extreme deep-sea environments.Here,we constructed a high-quality genome of the deep-sea Muddy arrowtooth eel(MAE,Ilyophis brunneus,captured below a depth of 3,500 m)by using Illumina,Pac Bio,and Hi-C sequencing.We compare it against those of shallow-water eel and other outgroups to explore the genetic basis that underlies the adaptive evolution to deep-sea biomes.The MAE genome was estimated to be 1.47 Gb and assembled into 14 pseudo-chromosomes.Phylogenetic analyses indicated that MAE diverged from its closely related shallow-sea species,European eel,~111.9 Mya and experienced a rapid evolution.The genome evolutionary analyses primarily revealed the following:(i)under high hydrostatic pressure,the positively selected gene TUBGCP3 and the expanded family MLC1 may improve the cytoskeleton stability;ACOX1 may enhance the fluidity of cell membrane and maintain transport activity;the expansion of ABCC12 gene family may enhance the integrity of DNA;(ii)positively selected HARS likely maintain the transcription ability at low temperatures;and(iii)energy metabolism under a food-limited environment may be increased by expanded and positively selected genes in AMPK and m TOR signaling pathways.展开更多
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (XDB42000000,XDB06010105)the National Key Research and Development Program of China (2018YFC0309800)+1 种基金the National Natural Science Foundation of China (41876179)the Major scientific and technological projects of Hainan Province (2019PT03)to S.P.H。
文摘High hydrostatic pressure,low temperature,and scarce food supply are the major factors that limit the survival of vertebrates in extreme deep-sea environments.Here,we constructed a high-quality genome of the deep-sea Muddy arrowtooth eel(MAE,Ilyophis brunneus,captured below a depth of 3,500 m)by using Illumina,Pac Bio,and Hi-C sequencing.We compare it against those of shallow-water eel and other outgroups to explore the genetic basis that underlies the adaptive evolution to deep-sea biomes.The MAE genome was estimated to be 1.47 Gb and assembled into 14 pseudo-chromosomes.Phylogenetic analyses indicated that MAE diverged from its closely related shallow-sea species,European eel,~111.9 Mya and experienced a rapid evolution.The genome evolutionary analyses primarily revealed the following:(i)under high hydrostatic pressure,the positively selected gene TUBGCP3 and the expanded family MLC1 may improve the cytoskeleton stability;ACOX1 may enhance the fluidity of cell membrane and maintain transport activity;the expansion of ABCC12 gene family may enhance the integrity of DNA;(ii)positively selected HARS likely maintain the transcription ability at low temperatures;and(iii)energy metabolism under a food-limited environment may be increased by expanded and positively selected genes in AMPK and m TOR signaling pathways.
