Ocimum metabolomics in response to abiotic stresses: Cold, flood, drought and salinity

PLoS One. 2019 Feb 6;14(2):e0210903. doi: 10.1371/journal.pone.0210903. eCollection 2019.

Abstract

Ocimum tenuiflorum is a widely used medicinal plant since ancient times and still continues to be irreplaceable due to its properties. The plant has been explored chemically and pharmacologically, however, the molecular studies have been started lately. In an attempt to get a comprehensive overview of the abiotic stress response in O. tenuiflorum, de novo transcriptome sequencing of plant leaves under the cold, drought, flood and salinity stresses was carried out. A comparative differential gene expression (DGE) study was carried out between the common transcripts in each stress with respect to the control. KEGG pathway analysis and gene ontology (GO) enrichment studies exhibited several modifications in metabolic pathways as the result of four abiotic stresses. Besides this, a comparative metabolite profiling of stress and control samples was performed. Among the cold, drought, flood and salinity stresses, the plant was most susceptible to the cold stress. Severe treatments of all these abiotic stresses also decreased eugenol which is the main secondary metabolite present in the O. tenuiflorum plant. This investigation presents a comprehensive analysis of the abiotic stress effects in O. tenuiflorum. Current study provides an insight to the status of pathway genes' expression that help synthesizing economically valuable phenylpropanoids and terpenoids related to the adaptation of the plant. This study identified several putative abiotic stress tolerant genes which can be utilized to either breed stress tolerant O. tenuiflorum through pyramiding or generating transgenic plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acclimatization / physiology*
  • Droughts
  • Floods
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant / physiology
  • Metabolic Networks and Pathways / physiology
  • Metabolome / physiology*
  • Metabolomics / methods
  • Ocimum sanctum / physiology*
  • Stress, Physiological / physiology*

Grants and funding

SR received Start Up Research Grant (Grant number- YSS/2014/001011) by Science and Engineering Research Board to conduct this study (http://www.serbonline.in/SERB/HomePage.do). SR designed, conceived, conducted the research plans and wrote the manuscript. SR, SS, RK, DV, MQA, AK performed the abiotic stress experiments and bioinformatics analysis. AKS and UND gave directions and suggestions for implementation of the experiments. All the authors have read and approved the final manuscript.