PagGRF12a interacts with PagGIF1b to regulate secondary xylem development through modulating PagXND1a expression in Populus alba × P. glandulosa

• 作者: Jinnan Wang Houjun Zhou Yanqiu Zhao Cheng Jiang Jihong Li Fang Tang Yingli Liu Shutang Zhao Jianjun Hu Xueqin Song Meng-Zhu Lu
• 来源期刊: 植物学报（英文版）
• 年，卷（期）: 2021,（10）
• 所属期刊栏目: Cell and Developmental Biology
• 页码范围: 1683-1694
• 页数: 12页
• 语种: 英文

摘要

Growth-regulating factors (GRFs) are important reg-ulators of plant development and growth, but their possible roles in xylem development in woody plants remain unclear. Here, we report that Populus alba × Papulus glandulosa PagGRF12a negatively regulates xylem development in poplar. PagGRF12a is ex-pressed in vascular tissues. Compared to non-transgenic control plants, transgenic poplar plants overexpressing PagGRF12a exhibited reduced xylem width and plants with repressed expression of PagGRF12a exhibited increased xylem width. Xylem NAC domain 1 (XND1) encodes a NAC do-main transcription factor that regulates xylem de-velopment and transcriptional analyses revealed that PagXND1a is highly upregulated in PagGRF12a-overexpressing plants and downregulated in PagGRF12a-suppressed plants, indicating that PagGRF12a may regulate xylem development through PagXND1a. Transient transcriptional assays and chromatin immunoprecipitation-polymerase chain reaction assays confirmed that PagGRF12a directly upregulates PagXND1a. In addition, PagGRF12a interacts with the GRF-Interacting Factor (GIF) PagGIF1b, and this interaction en-hances the effects of PagGRF12a on PagXND1a. Our results indicate that PagGRF12a inhibits xylem development by upregulating the expression of PagXND1a.