College of Horticulture and Landscape Architecture, Hunan Agricultural University, Changsha, China.
Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, MOE Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing, China.
J Exp Bot. 2019 Oct 24;70(20):5715-5730. doi: 10.1093/jxb/erz354.
Lateral organ development is essential for cucumber production. The protein kinase PINOID (PID) participates in distinct aspects of plant development by mediating polar auxin transport in different species. Here, we obtained a round leaf (rl) mutant that displayed extensive phenotypes including round leaf shape, inhibited tendril outgrowth, abnormal floral organs, and disrupted ovule genesis. MutMap+ analysis revealed that rl encodes a cucumber ortholog of PID (CsPID). A non-synonymous single nucleotide polymorphism in the second exon of CsPID resulted in an amino acid substitution from arginine to lysine in the rl mutant. Allelic testing using the mutant allele C356 with similar phenotypes verified that CsPID was the causal gene. CsPID was preferentially expressed in young leaf and flower buds and down-regulated in the rl mutant. Subcellular localization showed that the mutant form, Cspid, showed a dotted pattern of localization, in contrast to the continuous pattern of CsPID in the periphery of the cell and nucleus. Complementation analysis in Arabidopsis showed that CsPID, but not Cspid, can partially rescue the pid-14 mutant phenotype. Moreover, indole-3-acetic acid content was greatly reduced in the rl mutant. Transcriptome profiling revealed that transcription factors, ovule morphogenesis, and auxin transport-related genes were significantly down-regulated in the rl mutant. Biochemical analysis showed that CsPID physically interacted with a key polarity protein, CsREV (REVOLUTA). We developed a model in which CsPID regulates lateral organ morphogenesis and ovule development by stimulating genes related to auxin transport and ovule development.
侧生器官发育对黄瓜生产至关重要。蛋白激酶 PINOID（PID）通过调节不同物种中极性生长素的运输，参与植物发育的不同方面。在这里，我们获得了一个圆叶（rl）突变体，该突变体表现出广泛的表型，包括圆叶形状、抑制卷须生长、异常花器官和破坏胚珠发生。MutMap+分析表明，rl 编码 PID 的黄瓜同源物（CsPID）。CsPID 第二外显子中的一个非同义单核苷酸多态性导致 rl 突变体中从精氨酸到赖氨酸的氨基酸替换。使用具有相似表型的突变等位基因 C356 进行等位基因测试验证了 CsPID 是因果基因。CsPID 在幼叶和花蕾中优先表达，在 rl 突变体中下调。亚细胞定位显示突变形式 Cspid 呈现点状定位模式，而 CsPID 在细胞和核的外围呈现连续模式。在拟南芥中的互补分析表明，CsPID 而不是 Cspid 可以部分挽救 pid-14 突变体的表型。此外，rl 突变体中的吲哚-3-乙酸含量大大降低。转录组谱分析显示，转录因子、胚珠形态发生和生长素运输相关基因在 rl 突变体中显著下调。生化分析表明，CsPID 与关键极性蛋白 CsREV（REVOLUTA）物理相互作用。我们提出了一个模型，即 CsPID 通过刺激与生长素运输和胚珠发育相关的基因来调节侧生器官形态发生和胚珠发育。
