Transcriptome Profiling Provides Insights into Molecular Mechanism in Peanut Semi-dwarf Mutant (Arachis hypogaea L.)

Abstract BackgroundPlant height is the major agronomic trait and closely correlated to crop yield. Plant height development is an important area of plant developmental biology and numerous studies about its molecular genetic basis had been conducted on model plants and crops. However, little is known on the molecular mechanisms of peanut plant height.ResultsIn this study, a semi-dwarf peanut mutant was identified from Co60 gama ray induced mutant population and designated as semi-dwarf mutant 2 (sdm2). The height of sdm2 was only 59.3% of its wild line Fenghua 1 (FH1) at the mature stage. Both the internode number and internode length of sdm2 were less than those of FH1. Gene expression profiles of stem and leaf from both sdm2 and FH1 were analyzed using high throughput RNA sequencing. The identified differentially expressed genes (DEGs) were involved in hormone biosynthesis and signaling pathways, cell wall synthetic and metabolic pathways. BR, GA and IAA biosynthesis and signal transduction pathways were significantly enriched. The expression of several genes in both BR biosynthesis and signaling were found to be significantly down-regulated in stem and leaf of sdm2 as compared to FH1. Many transcription factor genes were identified as DEGs.ConclusionsA large number of genes were found to be differentially expressed between sdm2 and FH1. These results provide useful information for uncovering the molecular mechanism regulating peanut stem height. It could facilitate identification of causal genes for breeding advanced peanut varieties with semi-dwarf phenotype.