Data_Sheet_1_Identification and Functional Characterization of Squamosa Promoter Binding Protein-Like Gene TaSPL16 in Wheat (Triticum aestivum L.).PDF

Wheat (Triticum aestivum L.) is one of the most important crops in the world. Squamosa promoter binding protein-like (SPL) proteins are plant-specific transcript factors and play critical roles in plant growth and development. The functions of many SPL gene family members were well characterized in Arabidopsis and rice, in contrast, research on wheat SPL genes is lagging behind. In this study, we cloned and characterized TaSPL16, an orthologous gene of rice OsSPL16, in wheat. Three TaSPL16 homoeologs are located on the short arms of chromosome 7A, 7B, and 7D, and share more than 96% sequence identity with each other. All the TaSPL16 homoeologs have three exons and two introns, with a miR156 binding site in their last exons. They encode putative proteins of 407, 409, and 414 amino acid residues, respectively. Subcellular localization showed TaSPL16 distribution in the cell nucleus, and transcription activity of TaSPL16 was validated in yeast. Analysis of the spatiotemporal expression profile showed that TaSPL16 is highly expressed in young developing panicles, lowly expressed in developing seeds and almost undetectable in vegetative tissues. Ectopic expression of TaSPL16 in Arabidopsis causes a delay in the emergence of vegetative leaves (3–4 days late), promotes early flowering (5–7 days early), increases organ size, and affects yield-related traits. These results demonstrated the regulatory roles of TaSPL16 in plant growth and development as well as seed yield. Our findings enrich the existing knowledge on SPL genes in wheat and provide valuable information for further investigating the effects of TaSPL16 on plant architecture and yield-related traits of wheat.

普通小麦（Triticum aestivum L.）是全球最重要的粮食作物之一。SQUAMOSA启动子结合蛋白样（Squamosa promoter binding protein-like, SPL）蛋白是植物特有的转录因子，在植物生长发育过程中发挥关键调控作用。在拟南芥和水稻中，多个SPL基因家族成员的功能已得到充分解析，但小麦SPL基因的相关研究仍相对滞后。本研究从小麦中克隆并鉴定了水稻OsSPL16的同源基因TaSPL16。三个TaSPL16部分同源基因分别定位于7A、7B和7D染色体的短臂上，彼此间的序列一致性超过96%。所有TaSPL16部分同源基因均包含3个外显子和2个内含子，且在其最后一个外显子中存在miR156结合位点。它们分别编码长度为407、409和414个氨基酸残基的推定蛋白。亚细胞定位实验显示TaSPL16定位于细胞核中，且酵母实验验证了TaSPL16具有转录活性。时空表达谱分析表明，TaSPL16在幼嫩发育穗中高表达，在发育中的种子中表达量较低，而在营养组织中几乎无法检测到。在拟南芥中异位表达TaSPL16会导致营养叶萌发延迟（晚3~4天），促进开花提前（早5~7天），增加器官尺寸，并影响产量相关性状。上述结果证实了TaSPL16在植物生长发育以及种子产量调控中的重要功能。本研究丰富了当前关于小麦SPL基因的认知，为进一步探究TaSPL16对小麦株型及产量相关性状的调控效应提供了极具价值的参考依据。