Heat stress-responsive transcriptome analysis in heat susceptible and tolerant rice by high-throughput sequencing

As one of the most vital major food crops feeding almost half the earth's population, rice often suffers from heat stress in tropical and subtropical regions. To study rice heat stress tolerance mechanism is critical for breeding new heat tolerant rice varieties. We performed RNA-Seq analysis to check rice transcriptomic differences responsive to heat stress in both heat-tolerant (HT, HT54) and heat-sensitive (HS, HT13) lines. A sum of 0.603 billion reads were acquired on behalf of 32,391 unique genes. Compared with 0 h, a sum of 2275 genes showed enhanced regulation while 2270 genes showed inhibited regulation in the HS line at 12 h, contrarily 2603 genes showed enhanced regulation and 2900 genes showed inhibited regulation in the HT line. A sum of 1438 genes showed enhanced regulation and 1237 genes showed inhibited regulation in the HS line at 24 h, contrarily 1599 genes showed enhanced regulation and 1754 genes showed inhibited regulation in the HT line. About 22,490 genes were assigned to gene ontology (GO) term in terms of biological process, cellular component and molecular function categories. Compared with 0 h, a sum of 8 and 4 genes showed different expression (RFC ≥ 2.0) between the HT and HS rice lines at 12 and 24 h, respectively. This work most probably set a solid foundation for elucidating the heat stress tolerance mechanisms and crop genetic improvement in rice.