【原】Plant J|OsOFP19整合细胞分裂与BR信号途径负调控水稻株型

    OFPs（OVATE家族蛋白）的表征揭示了它们通过与不同类型的转录因子相互作用而发挥功能。然而，这些过程的分子基础知之甚少。在这里，我们报告OsOFP19负调控油菜素内酯（BR）反应，并整合它与细胞分裂模式，通过与DLT（DWARF AND LOW-TILLERING）和OSH1（Oryza sativa homeobox1）相互作用影响植物结构，包括谷粒形状。 OsOFP19的过量表达导致了半矮小的身材，叶片较厚，秆和根较强，这是由于表皮下组织细胞层增加所致。进一步的研究表明，OsOFP19与OSH1相互作用，这种相互作用增强了彼此的转录活性，并导致从背斜到周围细胞分裂的转变。此外，DLT与OsOFP19和OSH1相互作用，并在两种相互作用中起拮抗剂的作用。因此，OsOFP19，OSH1和DLT形成一个功能复合体，在调控植物生长发育过程中的BR信号传导和决定细胞分裂模式方面起着举足轻重的作用

Figure 7. Functions of OsOFP19, OSH1, and DLT in BR signaling and plant growth. (a) Protein level of OSH1 is not affected by BL treatment. CBB, Coomassie Brilliant Blue. (b) OSH1 suppresses the inhibitory effect of BR on accumulation of OsOFP19 protein. (c) OSH1 suppressed the BR-induced accumulation of DLT protein. (d) Effect of BL treatment on the protein levels of OsOFP19, OSH1, and DLT. (e) Dual-luciferase reporter assay shows the regulatory effects of OsOFP19, OSH1, and DLT on the expression of CYP734A6 gene. **, P< 0.01, t-test. (f) A working model for the cooperation of OsOFP19, OSH1, and DLT in BR signaling and plant growth and development.

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OsOFP19 modulates plant architecture by integrating cell division pattern and brassinosteroid signaling.

Yang C,et al Plant J 2017 Dec 05

Abstract:

Characterization of OFPs (OVATE Family Proteins) has revealed that they exert functions through interacting with different types of transcription factors. However, the molecular bases of these processes are poorly understood. Here, we report that OsOFP19 negatively modulates brassinosteroid (BR) response and integrates it with cell division pattern to affect plant architecture, including grain shape, through interaction with both DLT (DWARF AND LOW-TILLERING) and OSH1 (Oryza sativa homeobox1). Overexpression of OsOFP19 caused semi-dwarf stature with thicker leaves and stronger culms and roots, which is resulted from the increased cell layers in the sub-epidermal tissue. Further studies revealed that OsOFP19 interacts with OSH1, and this interaction enhances the transcriptional activity of each other and leads to a transition from anticlinal to periclinal cell division. Furthermore, DLT interacts with both OsOFP19 and OSH1 and acts as an antagonist in the two interactions. Therefore, OsOFP19, OSH1, and DLT form a functional complex which plays a pivotal role in modulating BR signaling and determining the cell division pattern during plant growth and development. This article is protected by copyright. All rights reserved.