Transcriptome analysis reveals regulatory framework for salt and osmotic tolerance in a succulent xerophyte

• Published in: BMC plant biology 2019-02, Vol.19 (1), p.88-88, Article 88
• Main Authors: Yin, Hongju, Li, Mengzhan, Li, Dingding, Khan, Sardar-Ali, Hepworth, Shelley R, Wang, Suo-Min
• Format: Article
• Language: English
• Subjects: Abiotic stress; Abscisic acid; Arabidopsis; Arabidopsis thaliana; Chlorophyll; DNA binding proteins; Drought; Enzymes; Gene expression; Genes; Genetic aspects; Genetically altered foods; Genomics; Hormones; Kinases; Metabolism; Network analysis; Novels; Osmosis; Osmotic stress; Physiological aspects; Plant hardiness; Plant hormones; Protein kinase; Protein kinases; Proteins; Proteolysis; Regulatory genes; RNA; RNA-sequencing; Salinity; Salinity tolerance; Salt; Salt stress (Botany); Salts; Stress; Stress response; Succulent plants; Transcription (Genetics); Transcription factors; Ubiquitin; Xerophytes
• ISSN: 1471-2229; 1471-2229
• DOI: 10.1186/s12870-019-1686-1

Zygophyllum xanthoxylum is a succulent xerophyte with remarkable tolerance to diverse abiotic stresses. Previous studies have revealed important physiological mechanisms and identified functional genes associated with stress tolerance. However, knowledge of the regulatory genes conferring stress tolerance in this species is poorly understood. Here, we present a comprehensive analysis of regulatory genes based on the transcriptome of Z. xanthoxylum roots exposed to osmotic stress and salt treatments. Significant changes were observed in transcripts related to known and obscure stress-related hormone signaling pathways, in particular abscisic acid and auxin. Significant changes were also found among key classes of early response regulatory genes encoding protein kinases, transcription factors, and ubiquitin-mediated proteolysis machinery. Network analysis shows a highly integrated matrix formed by these conserved and novel gene products associated with osmotic stress and salt in Z. xanthoxylum. Among them, two previously uncharacterized NAC (NAM/ATAF/CUC) transcription factor genes, ZxNAC083 (Unigene16368_All) and ZxNAC035 (CL6534.Contig1_All), conferred tolerance to salt and drought stress when constitutively overexpressed in Arabidopsis plants. This study provides a unique framework for understanding osmotic stress and salt adaptation in Z. xanthoxylum including novel gene targets for engineering stress tolerance in susceptible crop species.