Adaptive radiation in Orinus, an endemic alpine grass of the Qinghai-Tibet Plateau, based on comparative transcriptomic analysis

Copyright © 2022 Elsevier GmbH. All rights reserved.

Bibliographische Detailangaben
Veröffentlicht in:Journal of plant physiology. - 1979. - 277(2022) vom: 25. Okt., Seite 153786
1. Verfasser: Su, Xu (VerfasserIn)
Weitere Verfasser: Liu, Tao, Liu, Yu Ping, Harris, A J, Chen, Jin Yuan
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2022
Zugriff auf das übergeordnete Werk:Journal of plant physiology
Schlagworte:Journal Article Differentially expressed gene Orthologs Poaceae Single copy orthologous gene Synonymous substitution rate Whole-genome duplication
Beschreibung
Zusammenfassung:Copyright © 2022 Elsevier GmbH. All rights reserved.
The species of Orinus (Poaceae) are important alpine plants with a variety of phenotypic traits and potential usages in molecular breeding toward drought-tolerant forage crops. However, the genetic basis of evolutionary adaption and diversification in the genus is still unclear. In the present study, we obtained transcriptomes for the two most divergent species, O. thoroldii and O. kokonoricus, using the Illumina platform and de novo assembly. In total, we generated 23,029 and 24,086 unigenes with N50 values of 1188 and 1203 for O. thoroldii and O. kokonoricus respectively, and identified 19,005 pairs of putative orthologs between the two species of Orinus. For these orthologs, estimations of non-synonymous/synonymous substitution rate ratios indicated that 568 pairs may be under strongly positive selection (Ka/Ks > 1), and Gene Ontogeny (GO) enrichment analysis revealed that significantly enriched pathways were in DNA repair and resistance to abiotic stress. Meanwhile, the divergence times of species between O. thoroldii and O. kokonoricus occurred 3.2 million years ago (Mya), and the recent evolutionary branch is an allotetraploid species, Cleistogenes songorica. We also detected a Ks peak of ∼0.60 for Orinus. Additionally, we identified 188 pairs of differentially expressed genes (DEGs) between the two species of Orinus, which were significantly enrich in stress resistance and lateral root development. Thus, we considered that the species diversification and evolutionary adaption of this genus was initiated by environmental selection, followed by phenotypic differentiation, finally leading to niche separation in the Qinghai-Tibet Plateau
Beschreibung:Date Completed 22.09.2022
Date Revised 22.09.2022
published: Print-Electronic
Citation Status MEDLINE
ISSN:1618-1328
DOI:10.1016/j.jplph.2022.153786