NF-YB1-YC12-bHLH144 complex directly activates Wx to regulate grain quality in rice (Oryza sativa L.)
NF-YB1-YC12-bHLH144 complex directly activates Wx to regulate grain quality in rice (Oryza sativa L.)
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DOI：
10.1111/pbi.13048
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发表时间：
2019-07-01
影响因子：
13.8
通讯作者：
Zhang, Jian
中科院分区：
文献类型：
--
作者：
Bello, Babatunde Kazeem;Hou, Yuxuan;Zhang, Jian
种子发育调控基因的鉴定是水稻籽粒品质遗传改良的关键。 NF-Ys是重要的转录因子，但其在水稻籽粒品质控制中的作用及其潜在分子机制仍知之甚少。在这里，我们报告了水稻 NF-Y 异源三聚体复合物 NF-YB1-YC12-bHLH144 的功能表征，该复合物是通过 NF-YB1 与 NF-YC12，然后按顺序结合 bHLH144 形成的。每个复杂基因的敲除都会导致所有突变体的籽粒品质发生改变，并导致 crnf-yb1 和 crnf-yc12 的籽粒尺寸减小。 RNA-seq 分析鉴定了 1496 个通常受 NF-YB1 和 NF-YC12 调控的基因，包括关键的颗粒结合淀粉合酶基因 Wx。 NF-YC12和bHLH144维持NF-YB1的稳定性，使其免受泛素/26S蛋白酶体介导的降解，而NF-YB1直接与Wx启动子的“G-box”结构域结合并激活Wx转录，从而调节稻米品质。最后，我们揭示了一条由 NF-YB1-YC12-bHLH144 复合物控制的新型谷物品质调控途径，该途径在水稻遗传改良方面具有巨大潜力。
Identification of seed development regulatory genes is the key for the genetic improvement in rice grain quality. NF-Ys are the important transcription factors, but their roles in rice grain quality control and the underlying molecular mechanism remain largely unknown. Here, we report the functional characterization a rice NF-Y heterotrimer complex NF-YB1-YC12-bHLH144, which is formed by the binding of NF-YB1 to NF-YC12 and then bHLH144 in a sequential order. Knock-out of each of the complex genes resulted in alteration of grain qualities in all the mutants as well as reduced grain size in crnf-yb1 and crnf-yc12. RNA-seq analysis identified 1496 genes that were commonly regulated by NF-YB1 and NF-YC12, including the key granule-bound starch synthase gene Wx. NF-YC12 and bHLH144 maintain NF-YB1 stability from the degradation mediated by ubiquitin/26S proteasome, while NF-YB1 directly binds to the 'G-box' domain of Wx promoter and activates Wx transcription, hence to regulate rice grain quality. Finally, we revealed a novel grain quality regulatory pathway controlled by NF-YB1-YC12-bHLH144 complex, which has great potential for rice genetic improvement.