Maize Research Institute, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land, Southwest University, Beibei District, Chongqing, People's Republic of China.
J Exp Bot. 2021 Jun 22;72(13):4757-4772. doi: 10.1093/jxb/erab157.
Leaf angle and leaf orientation value (LOV) are critical agronomic traits for maize plant architecture. The functions of NUCLEAR FACTOR Y (NF-Y) members in regulating plant architecture have not been reported yet. Here, we identified a regulator of maize plant architecture, NF-Y subunit C13 (ZmNF-YC13). ZmNF-YC13 was highly expressed in the leaf base zone of maize plants. ZmNF-YC13 overexpressing plants showed upright leaves with narrow leaf angle and larger LOV, while ZmNF-YC13 knockout plants had larger leaf angle and smaller LOV compared with wild-type plants. The changes in plant architecture were due to the changes in the expression of cytochrome P450 family members. ZmNF-YC13 interacts with two NF-Y subunit B members (ZmNF-YB9 and ZmNF-YB10) of the LEAFY COTYLEDON1 sub-family, and further recruits NF-Y subunit A (ZmNF-YA3) to form two NF-Y complexes. The two complexes can both activate the promoters of transcriptional repressors (ZmWRKY76 and ZmBT2), and the promoters of PLASTOCHRON group genes can be repressed by ZmWRKY76 and ZmBT2 in maize protoplasts. We propose that ZmNF-YC13 functions as a transcriptional regulator and, together with ZmNF-YBs and ZmNF-YA3, affects plant architecture by regulating the expression of ZmWRKY76 and ZmBT2, which repress the expression of cytochrome P450 family members in PLASTOCHRON branch.
叶角和叶向值（LOV）是玉米植株结构的重要农艺性状。NF-Y 成员在调节植物结构中的功能尚未报道。在这里，我们鉴定了一个玉米植株结构的调节因子，NF-Y 亚基 C13（ZmNF-YC13）。ZmNF-YC13 在玉米植株的叶基部区域高度表达。ZmNF-YC13 过表达植株表现出直立的叶片，叶角较窄，LOV 较大，而 ZmNF-YC13 敲除植株的叶角较大，LOV 较小，与野生型植株相比。植物结构的变化是由于细胞色素 P450 家族成员表达的变化。ZmNF-YC13 与 LEAFY COTYLEDON1 亚家族的两个 NF-Y 亚基 B 成员（ZmNF-YB9 和 ZmNF-YB10）相互作用，并进一步招募 NF-Y 亚基 A（ZmNF-YA3）形成两个 NF-Y 复合物。这两个复合物都可以激活转录抑制因子（ZmWRKY76 和 ZmBT2）的启动子，而 PLASTOCHRON 组基因的启动子可以在玉米原生质体中被 ZmWRKY76 和 ZmBT2 抑制。我们提出 ZmNF-YC13 作为一个转录调节因子，与 ZmNF-YBs 和 ZmNF-YA3 一起，通过调节 ZmWRKY76 和 ZmBT2 的表达来影响植物结构，从而抑制 PLASTOCHRON 分支中细胞色素 P450 家族成员的表达。
