Transcriptome-Wide m6A Methylome Profiling in Sorghum following GA3 Treatment under Salt Stress.

Abstract

Sorghum (“Jitian 3”) is a salt-tolerant seed cultivar used regularly in marginal lands, such as those with saline soils. Herein, we examined the potential of employing gibberellic acid (GA3) as an inducer of sorghum development during salt stress. Thus far, there have been no reports on the signaling network involved in the GA3-mediated regulation of sorghum development. In this study, we demonstrated that the stimulating properties of 50 mg/L GA3 on sorghum development was far superior to other GA3 concentrations under a 150 mM NaCl salinity condition. Furthermore, using methylated RNA immunoprecipitation sequencing (MeRIP-seq), we established an m6A methylation (m6A-M) profile in sorghum following exposure to 50 mg/L GA3. Overall, 23,363 m6A peaks and 16,200 m6A genes were screened among the GA3-treated and control leaves. These identified peaks were shown to be primarily enriched in the coding, as were the 3′- and 5′-untranslated regions. In addition, we employed m6A and transcript expression cross-analysis to identify 70 genes with differential transcript expression and simultaneous m6A-M. Intriguingly, the principal gene, LOC8066282, which is associated with LOC8084853, was shown to be intricately linked to the phosphatidylinositol signaling, which in turn regulates sorghum development and response to salt stress. This investigation presents a novel RNA m6A-M profile in sorghum, which may facilitate new insights into the underlying signaling behind salt stress resistance. This work will also benefit future investigations on foreign GA3 administration of sorghum.