Research
| Title： | Pseudo-chromosome-length genome assembly for a deep-sea eel Ilyophis brunneus sheds light on the deep-sea adaptation |
|---|---|
| First author： | Chen, Jie; Zeng, Honghui; Lv, Wenqi; Sun, Ning; Wang, Cheng; Xu, Wenjie; Hu, Mingliang; Gan, Xiaoni; He, Lisheng; He, Shunping; Fang, Chengchi |
| Journal： | SCIENCE CHINA-LIFE SCIENCES |
| Years： | 2023 |
| DOI： | 10.1007/s11427-022-2251-8 |
| Abstract： | 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, PacBio, 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, similar to 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 mTOR signaling pathways. |
