College of Agriculture, Northeast Agricultural University, Harbin 150030, China.
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Int J Mol Sci. 2022 Aug 3;23(15):8643. doi: 10.3390/ijms23158643.
Soybean plant height and branching affect plant architecture and yield potential in soybean. In this study, the mutant was obtained by treating the cultivar Zhongpin 661 with ethylmethane sulfonate. The mutant plants were shorter and more branched than the wild type. The genetic analysis showed that the mutant trait was controlled by a semi-dominant gene. The candidate gene was fine-mapped to a 91 kb interval on Chromosome 9 by combining BSA-seq and linkage analysis. Sequence analysis revealed that encoding an Aux/IAA protein (GmIAA27) was mutated from C to T in the second exon of the coding region, resulting to amino acid substitution of proline to leucine. Overexpression of the mutant type of this gene in inhibited apical dominance and promoted lateral branch development. Expression analysis of and auxin response genes revealed that some GH3 genes were induced. GmIAA27 relies on auxin to interact with TIR1, whereas Gmiaa27 cannot interact with TIR1 owing to the mutation in the degron motif. Identification of this unique gene that controls soybean plant height and branch development provides a basis for investigating the mechanisms regulating soybean plant architecture development.
大豆植株的高度和分枝影响大豆的植株结构和产量潜力。在这项研究中，通过用乙烷磺酸处理品种中品 661 获得了 突变体。突变体植株比野生型更矮、分枝更多。遗传分析表明，突变性状由一个半显性基因控制。通过结合 BSA-seq 和连锁分析，将候选基因精细定位到 9 号染色体上的 91kb 区间。序列分析表明，编码Aux/IAA 蛋白（GmIAA27）的基因在编码区的第二个外显子中从 C 突变为 T，导致脯氨酸到亮氨酸的氨基酸取代。该基因的突变型在 中的过表达抑制了顶端优势，促进了侧枝的发育。对 和生长素响应基因的表达分析表明，一些 GH3 基因被诱导。GmIAA27 依赖生长素与 TIR1 相互作用，而 Gmiaa27 由于在 degron 基序中发生突变而不能与 TIR1 相互作用。鉴定出这种控制大豆株高和分枝发育的独特基因，为研究调控大豆植株结构发育的机制提供了基础。
