The molecular mechanism of SPOROCYTELESS/NOZZLE in controlling Arabidopsis ovule development

• Published in: Cell research Vol. 25; no. 1; pp. 121 - 134
• Main Authors: Wei, Baoye, Zhang, Jinzhe, Pang, Changxu, Yu, Hao, Guo, Dongshu, Jiang, Hao, Ding, Mingxin, Chen, Zhuoyao, Tao, Qing, Gu, Hongya, Qu, Li-Jia, Qin, Genji
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.01.2015; Nature Publishing Group
• Subjects: 631/449/1659; 631/449/2653; 631/80/86; Amino Acid Sequence; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - chemistry; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Biomedical and Life Sciences; Cell Biology; Gene Expression Regulation, Plant; Life Sciences; Molecular Sequence Data; Nuclear Pore Complex Proteins - genetics; Nuclear Pore Complex Proteins - metabolism; Nuclear Proteins - chemistry; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Original; original-article; Ovule - genetics; Ovule - growth & development; Ovule - metabolism; Plant reproduction; Protein Interaction Maps; Repressor Proteins - chemistry; Repressor Proteins - genetics; Repressor Proteins - metabolism; 分子机制; 喷嘴; 技术合作项目; 拟南芥; 控制; 植物繁殖; 胚珠发育; 转录因子; sporogenesis; TPL/TPR co-repressors; TCP transcription factors; transcriptional repressor
• ISSN: 1001-0602; 1748-7838
• DOI: 10.1038/cr.2014.145

Ovules are essential for plant reproduction and develop into seeds after fertilization. SPOROCYTELESS/NOZZLE （SPL/NZZ） has been known for more than 15 years as an essential factor for ovule development in Arabidopsis, but the biochemical nature of SPL function has remained unsolved. Here, we demonstrate that SPL functions as an adaptor-like transcriptional repressor. We show that SPL recruits TOPLESS/TOPLESS-RELATED （TPL/ TPR） co-repressors to inhibit the CINCINNATA （CIN）-like TEOSINTE BRANCHED1/CYCLOIDEA/PCF （TCP） transcription factors. We reveal that SPL uses its EAR motif at the C-terminal end to recruit TPL/TPRs and its N-terminal part to bind and inhibit the TCPs. We demonstrate that either disruption of TPL/TPRs or overexpression of TCPs partially phenocopies the defects of megasporogenesis in spl. Moreover, disruption of TCPs causes phenotypes that resemble spl-D gain-of-function mutants. These results define the action mechanism for SPL, which along with TPL/TPRs controls ovule development by repressing the activities of key transcription factors. Our findings suggest that a similar gene repression strategy is employed by both plants and fungi to control sporogenesis.