State Key Laboratory of Crop Biology, College of Agronomic Sciences, Shandong Agricultural University, Tai'an, Shandong 271018, China.
Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Plant Physiol. 2022 Aug 29;190(1):500-515. doi: 10.1093/plphys/kiac308.
Leaf angle is an important agronomic trait determining maize (Zea mays) planting density and light penetration into the canopy and contributes to the yield gain in modern maize hybrids. However, little is known about the molecular mechanisms underlying leaf angle beyond the ZmLG1 (liguleless1) and ZmLG2 (Liguleless2) genes. In this study, we found that the transcription factor (TF) ZmBEH1 (BZR1/BES1 homolog gene 1) is targeted by ZmLG2 and regulates leaf angle formation by influencing sclerenchyma cell layers on the adaxial side. ZmBEH1 interacted with the TF ZmBZR1 (Brassinazole Resistant 1), whose gene expression was also directly activated by ZmLG2. Both ZmBEH1 and ZmBZR1 are bound to the promoter of ZmSCL28 (SCARECROW-LIKE 28), a third TF that influences leaf angle. Our study demonstrates regulatory modules controlling leaf angle and provides gene editing targets for creating optimal maize architecture suitable for dense planting.
叶角是一个重要的农艺性状，决定了玉米（Zea mays）的种植密度和光穿透树冠的能力，并有助于现代玉米杂交种的产量增加。然而，除了 ZmLG1（无叶舌 1）和 ZmLG2（无叶舌 2）基因之外，人们对叶角的分子机制知之甚少。在这项研究中，我们发现转录因子（TF）ZmBEH1（BZR1/BES1 同源基因 1）是 ZmLG2 的靶标，并通过影响近轴侧的厚壁细胞层来调节叶角的形成。ZmBEH1 与 TF ZmBZR1（Brassinazole Resistant 1）相互作用，其基因表达也被 ZmLG2 直接激活。ZmBEH1 和 ZmBZR1 都与 ZmSCL28（SCARECROW-LIKE 28）的启动子结合，ZmSCL28 是第三个影响叶角的 TF。我们的研究证明了控制叶角的调节模块，并为创造适合密植的最佳玉米结构提供了基因编辑目标。
