Transcriptome sequencing of okra (Abelmoschus esculentus L. Moench) uncovers differently expressed genes responding to drought stress

• Published in: Journal of plant biochemistry and biotechnology 2020-06, Vol.29 (2), p.155-170
• Main Authors: Shi, Denghong, Wang, Jiyue, Bai, Yu, Liu, Yan
• Format: Article
• Language: English
• Subjects: Abelmoschus esculentus; Biomedical and Life Sciences; Biosynthesis; Cell Biology; Drought; Gene expression; Genes; Gluconeogenesis; Glycolysis; Herbal medicine; Life Sciences; Medicinal plants; Metabolism; Metabolites; Metal ions; Molecular modelling; Next-generation sequencing; Nucleotides; Okra; Original Article; Oxidation; Plant Biochemistry; Protein Science; Receptors; Reduction (metal working); Ribonucleic acid; RNA; Secondary metabolites; Seedlings; Single-nucleotide polymorphism; Stress; Transcription factors
• ISSN: 0971-7811; 0974-1275
• DOI: 10.1007/s13562-019-00528-w

Drought affects the growth and development of plants and can cause crop failure. As an important edible and medicinal plant, okra ( Abelmoschus esculentus L. Moench) is very popular in China and shows strong resistance to drought. In this study, gene expression profiles of okra leaves were investigated under water-limited conditions at the seedling stage. A total of 94,769 unigenes with an average length of 1921 bp and an N90 of 981 bp were obtained through next-generation sequencing. Furthermore, 38.18% of total unigenes were annotated in NT, NR, COG, KEGG, and SwissProt databases. A total of 2276, 5626, 11,719, 14,892, 855, 4593, and 5170 differentially expressed genes (DEGs) in seven pairwise comparisons (A5 vs. A0; A7 vs. A0; A15 vs. A0; A20 vs. A0; A7 vs. A5; A15 vs. A7, and A20 vs. A15) were identified. Among these, 22,751 DEGs were up-regulated, and the number was slightly more than that of the down-regulated DEGs. The number of up-regulated DEGs among different samples increased with increasing drought stress. We identified that the majority of DEGs were related to “integral component of membrane”, “oxidation–reduction process”, and “metal ion binding” categories. Pathway analysis revealed that most DEGs were enriched in “Biosynthesis of secondary metabolites”, “Carbon metabolism”, and “Glycolysis/Gluconeogenesis pathways”. Additionally, a total of 17,456 simple sequence repeat motifs, 47,9831 single nucleotide polymorphisms, and 3746 transcription factors were identified in this study. RNA-Seq data were also verified by RT-qPCR. Our findings engender a further understanding of molecular mechanisms in response to drought stress.