Genome wide transcriptome analysis reveals vital role of heat responsive genes in regulatory mechanisms of lentil (Lens culinaris Medikus)

• Published in: Scientific reports Vol. 9; no. 1; pp. 12976 - 19
• Main Authors: Singh, Dharmendra, Singh, Chandan Kumar, Taunk, Jyoti, Jadon, Vasudha, Pal, Madan, Gaikwad, Kishor
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 10-09-2019; Nature Publishing Group
• Subjects: 38/91; 631/449/2661/2663; 631/61/447/8; Antioxidants; Ascorbic acid; Cell walls; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Plant; Genetic analysis; Genome, Plant; Genomes; Genotype; Genotype & phenotype; Genotypes; Germination; Glutathione peroxidase; Glycine betaine; Heat tolerance; Heat-Shock Response; Humanities and Social Sciences; Insertion; L-Ascorbate peroxidase; Lens Plant - genetics; Lens Plant - growth & development; Metabolites; Microsatellites; multidisciplinary; Phenotyping; Physiology; Plant Proteins - genetics; Pollen; Polymerase chain reaction; Polymorphism, Single Nucleotide; Proline; Science; Science (multidisciplinary); Single-nucleotide polymorphism; Stigmas (botany); Superoxide dismutase; Transcriptome
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-49496-0

The present study reports the role of morphological, physiological and reproductive attributes viz. membrane stability index (MSI), osmolytes accumulations, antioxidants activities and pollen germination for heat stress tolerance in contrasting genotypes. Heat stress increased proline and glycine betaine (GPX) contents, induced superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione peroxidase (GPX) activities and resulted in higher MSI in PDL-2 (tolerant) compared to JL-3 (sensitive).
In vitro
pollen germination of tolerant genotype was higher than sensitive one under heat stress.
In vivo
stressed pollens of tolerant genotype germinated well on stressed stigma of sensitive genotype, while stressed pollens of sensitive genotype did not germinate on stressed stigma of tolerant genotype.
De novo
transcriptome analysis of both the genotypes showed that number of contigs ranged from 90,267 to 104,424 for all the samples with N
50
ranging from 1,755 to 1,844 bp under heat stress and control conditions. Based on assembled unigenes, 194,178 high-quality Single Nucleotide Polymorphisms (SNPs), 141,050 microsatellites and 7,388 Insertion-deletions (Indels) were detected. Expression of 10 genes was evaluated using quantitative Real Time Polymerase Chain Reaction (RT-qPCR). Comparison of differentially expressed genes (DEGs) under different combinations of heat stress has led to the identification of candidate DEGs and pathways. Changes in expression of physiological and pollen phenotyping related genes were also reaffirmed through transcriptome data. Cell wall and secondary metabolite pathways are found to be majorly affected under heat stress. The findings need further analysis to determine genetic mechanism involved in heat tolerance of lentil.