Global transcriptome analysis of alfalfa reveals six key biological processes of senescent leaves

Jianbo Yuan; Xinbo Sun; Tao Guo; Yuehui Chao; Liebao Han

doi:10.7717/peerj.8426

Global transcriptome analysis of alfalfa reveals six key biological processes of senescent leaves

PeerJ. 2020 Jan 21:8:e8426. doi: 10.7717/peerj.8426. eCollection 2020.

Authors

Jianbo Yuan¹, Xinbo Sun², Tao Guo¹, Yuehui Chao¹, Liebao Han¹

Affiliations

¹ College of Grassland Science, Beijing Forestry University, Beijing, China.
² College of Agronomy, Hebei Agricultural University, Key Laboratory of Crop Growth Regulation of Hebei Province, China.

Abstract

Leaf senescence is a complex organized developmental stage limiting the yield of crop plants, and alfalfa is an important forage crop worldwide. However, our understanding of the molecular mechanism of leaf senescence and its influence on biomass in alfalfa is still limited. In this study, RNA sequencing was utilized to identify differentially expressed genes (DEGs) in young, mature, and senescent leaves, and the functions of key genes related to leaf senescence. A total of 163,511 transcripts and 77,901 unigenes were identified from the transcriptome, and 5,133 unigenes were differentially expressed. KEGG enrichment analyses revealed that ribosome and phenylpropanoid biosynthesis pathways, and starch and sucrose metabolism pathways are involved in leaf development and senescence in alfalfa. GO enrichment analyses exhibited that six clusters of DEGs are involved in leaf morphogenesis, leaf development, leaf formation, regulation of leaf development, leaf senescence and negative regulation of the leaf senescence biological process. The WRKY and NAC families of genes mainly consist of transcription factors that are involved in the leaf senescence process. Our results offer a novel interpretation of the molecular mechanisms of leaf senescence in alfalfa.

Keywords: Alfalfa; Differentially expressed genes; Leaf senescence; Transcriptome.

Grants and funding

This work was supported by the Fundamental Research Funds for the Central Universities (2019ZY11). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.