Genome of Laudakia sacra Provides New Insights into High-Altitude Adaptation of Ectotherms

• Published in: International journal of molecular sciences Vol. 23; no. 17; p. 10081
• Main Authors: Yan, Chaochao, Zhang, Zhi-Yi, Lv, Yunyun, Wang, Zeng, Jiang, Ke, Li, Jia-Tang
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.09.2022; MDPI
• Subjects: Adaptation; Altitude; Animals; comparative genomics; de novo genome; DNA repair; Electron transport; Erythropoiesis; Evolution & development; Genes; Genomes; Genomic analysis; High altitude environments; Hot springs; Hypoxia; lizard; Metabolism; MSH2 protein; Mutation; NF-AT protein; Oxidative phosphorylation; Oxygen tension; Phosphorylation; Snakes; Ultraviolet radiation; UV damage; Tibet
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms231710081

Anan’s rock agama (Laudakia sacra) is a lizard species endemic to the harsh high-altitude environment of the Qinghai–Tibet Plateau, a region characterized by low oxygen tension and high ultraviolet (UV) radiation. To better understand the genetic mechanisms underlying highland adaptation of ectotherms, we assembled a 1.80-Gb L. sacra genome, which contained 284 contigs with an N50 of 20.19 Mb and a BUSCO score of 93.54%. Comparative genomic analysis indicated that mutations in certain genes, including HIF1A, TIE2, and NFAT family members and genes in the respiratory chain, may be common adaptations to hypoxia among high-altitude animals. Compared with lowland reptiles, MLIP showed a convergent mutation in L. sacra and the Tibetan hot-spring snake (Thermophis baileyi), which may affect their hypoxia adaptation. In L. sacra, several genes related to cardiovascular remodeling, erythropoiesis, oxidative phosphorylation, and DNA repair may also be tailored for adaptation to UV radiation and hypoxia. Of note, ERCC6 and MSH2, two genes associated with adaptation to UV radiation in T. baileyi, exhibited L. sacra-specific mutations that may affect peptide function. Thus, this study provides new insights into the potential mechanisms underpinning high-altitude adaptation in ectotherms and reveals certain genetic generalities for animals’ survival on the plateau.