College of Life Science, Shandong Normal University, Jinan, People's Republic of China.
Biotechnology Research Center, Shandong Academy of Agricultural Sciences, Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, People's Republic of China.
BMC Genomics. 2020 Mar 5;21(1):211. doi: 10.1186/s12864-020-6614-0.
Plant height, mainly decided by main stem height, is the major agronomic trait and closely correlated to crop yield. A number of studies had been conducted on model plants and crops to understand the molecular and genetic basis of plant height. However, little is known on the molecular mechanisms of peanut main stem height.
In this study, a semi-dwarf peanut mutant was identified from Co γ-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. The sdm2 has less internode number and short internode length to compare with FH1. Gene expression profiles of stem and leaf from both sdm2 and FH1 were analyzed using high throughput RNA sequencing. The 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 BR biosynthesis and signaling were found to be significantly down-regulated in sdm2 as compared to FH1. Many transcription factors encoding genes were identified as DEGs.
A large number of genes were found 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 peanut varieties with semi-dwarf phenotype.
株高主要由主茎高度决定，是主要的农艺性状，与作物产量密切相关。许多研究已经在模式植物和作物上进行，以了解植物株高的分子和遗传基础。然而，关于花生主茎高度的分子机制知之甚少。
本研究从 Co γ 射线诱导的突变体群体中鉴定出一个半矮化花生突变体，并将其命名为半矮化突变体 2（sdm2）。sdm2 在成熟阶段的高度仅为其野生系丰花 1（FH1）的 59.3%。sdm2 的节数较少，节间长度较短。利用高通量 RNA 测序分析了 sdm2 和 FH1 的茎和叶的基因表达谱。差异表达基因（DEGs）参与激素生物合成和信号通路、细胞壁合成和代谢途径。BR、GA 和 IAA 生物合成和信号转导途径显著富集。与 FH1 相比，sdm2 中 BR 生物合成和信号转导的几个基因的表达明显下调。鉴定出许多编码转录因子的基因作为 DEGs。
在 sdm2 和 FH1 之间发现了大量差异表达的基因。这些结果为揭示调控花生茎高的分子机制提供了有用信息。它可以促进鉴定具有半矮化表型的花生品种的因果基因。
