Hong Yantao, Chen Longfei, Du Li-pu, Su Zhenqi, Wang Jinfen, Ye Xingguo, Qi Lin, Zhang Zengyan
The National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Funct Integr Genomics. 2014 Jun;14(2):341-9. doi: 10.1007/s10142-014-0380-5. Epub 2014 Jun 3.
Bread wheat (Triticum aestivum L.) is a major staple crop in the world. Grain weight is a major factor of grain yield in wheat, and the identification of candidate genes associated with grain weight is very important for high-yield breeding of wheat. TaGW2 is an orthologous gene of rice OsGW2 that negatively regulates the grain width and weight in rice. There are three TaGW2 homoeologs in bread wheat, TaGW2A, TaGW2B, and TaGW2D. In this study, a specific TaGW2-RNA interference (RNAi) cassette was constructed and transformed into a Chinese bread wheat variety 'Shi 4185' with small grain. The transcript levels of TaGW2A, TaGW2B, and TaGW2D were simultaneously downregulated in TaGW2-RNAi transgenic wheat lines. Compared with the controls, TaGW2-underexpressing transgenic lines displayed significantly increases in the grain width and weight, suggesting that TaGW2 negatively regulated the grain width and weight in bread wheat. Further transcript analysis showed that in different bread wheat accessions, the transcript abundance of TaGW2A was negatively associated with the grain width.
普通小麦（Triticum aestivum L.）是世界上的主要粮食作物。粒重是小麦产量的一个主要因素，鉴定与粒重相关的候选基因对于小麦高产育种非常重要。TaGW2是水稻OsGW2的直系同源基因，它对水稻的粒宽和粒重起负调控作用。普通小麦中有三个TaGW2同源基因，即TaGW2A、TaGW2B和TaGW2D。在本研究中，构建了一个特异性TaGW2-RNA干扰（RNAi）盒，并将其转化到小粒的中国普通小麦品种‘石4185’中。在TaGW2-RNAi转基因小麦株系中，TaGW2A、TaGW2B和TaGW2D的转录水平同时下调。与对照相比，TaGW2表达下调的转基因株系的粒宽和粒重显著增加，这表明TaGW2对普通小麦的粒宽和粒重起负调控作用。进一步的转录分析表明，在不同的普通小麦材料中，TaGW2A的转录丰度与粒宽呈负相关。
