Light-harvesting chlorophyll a/b-binding protein-coding genes in jatropha and the comparison with castor, cassava and arabidopsis

Yongguo Zhao; Hua Kong; Yunling Guo; Zhi Zou

doi:10.7717/peerj.8465

Light-harvesting chlorophyll a/b-binding protein-coding genes in jatropha and the comparison with castor, cassava and arabidopsis

PeerJ. 2020 Jan 28:8:e8465. doi: 10.7717/peerj.8465. eCollection 2020.

Authors

Yongguo Zhao^{1

2}, Hua Kong², Yunling Guo², Zhi Zou²

Affiliations

¹ Guangdong University of Petrochemical Technology, Maoming, China.
² Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture and Rural Affairs, Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Science, Haikou, China.

Abstract

The Lhc (light-harvesting chlorophyll a/b-binding protein) superfamily represents a class of antennae proteins that play indispensable roles in capture of solar energy as well as photoprotection under stress conditions. Despite their importance, little information has been available beyond model plants. In this study, we presents a first genome-wide analysis of Lhc superfamily genes in jatropha (Jatropha curcas L., Euphorbiaceae), an oil-bearing plant for biodiesel purpose. A total of 27 members were identified from the jatropha genome, which were shown to distribute over nine out of the 11 chromosomes. The superfamily number is comparable to 28 present in castor (Ricinus communis, Euphorbiaceae), but relatively less than 35 in cassava (Manihot esculenta, Euphorbiaceae) and 34 in arabidopsis (Arabidopsis thaliana) that experienced one or two recent whole-genome duplications (WGDs), respectively. In contrast to a high number of paralogs present in cassava and arabidopsis, few duplicates were found in jatropha as observed in castor, corresponding to no recent WGD occurred in these two species. Nevertheless, 26 orthologous groups representing four defined families were found in jatropha, and nearly one-to-one orthologous relationship was observed between jatropha and castor. By contrast, a novel group named SEP6 was shown to have been lost in arabidopsis. Global transcriptome profiling revealed a predominant expression pattern of most JcLhc superfamily genes in green tissues, reflecting their key roles in photosynthesis. Moreover, their expression profiles upon hormones, drought, and salt stresses were also investigated. These findings not only improve our knowledge on species-specific evolution of the Lhc supergene family, but also provide valuable information for further studies in jatropha.

Keywords: Evolution; Harvesting chlorophyll a/b-binding protein; Lhc superfamily; Synteny analysis; Arabidopsis thaliana; Expression profile; Jatropha curcas; Manihot esculenta; Ricinus communis; Whole-genome duplication.

Grants and funding

This work was supported by the National Natural Science Foundation of China (31700580 and 31971688), the Natural Science Foundation of Hainan province (319MS093), the Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences (1630022019017 and 1630052017011), and the Research Fund of Guangdong University of Petrochemical Technology (2018rc55). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.