Constitutive down-regulation of SiSGR gene is related to green millet in Setaria italica
Constitutive down-regulation of SiSGR gene is related to green millet in Setaria italica
复制标题
谷子SiSGR基因的组成性下调与青小米有关
DOI：
10.1134/s1021443717040045
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发表时间：
2017-07-01
影响因子：
1.4
通讯作者：
Han, Y. H.
中科院分区：
文献类型：
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作者：
Cheng, L.;Zhang, B.;Han, Y. H.
谷色是评价谷子品质的一个重要指标。Beauv.）。由于类胡萝卜素的积累，大多数品种都是黄色的。然而，也有一些谷子胚芽生产暗绿色谷子。为了阐明叶绿素保持表型的分子机制，本研究以具有绿色粟色的大青谷和具有黄色粟色的晋谷21为材料。大青谷脱皮谷子中总类胡萝卜素含量为0.024 mg/g，晋谷21脱皮谷子中总类胡萝卜素含量为0.038 mg/g。研究了两个谷子品种籽粒发育3个阶段类胡萝卜素结构基因的转录水平。类胡萝卜素生物合成相关基因SiPSY 3、SiPDS、SiZ-ISO、SiLCYB和SiCYP 97 C在大青谷的表达量显著高于金谷21，但这与两个品种间类胡萝卜素水平的差异不一致。有趣的是，SiSGR，拟南芥，番茄和水稻中的STAY-GREEN基因的同源物，在大青谷成熟过程中组成型下调。此外，在籽粒成熟过程中，大青谷的叶绿素总含量始终高于津谷21。这些证据表明，SiSGR是调控暗绿色谷子叶绿素保持的关键基因。
Millet colour is an important index to evaluate the quality of dehulled foxtail millet (Setaria italica (L.) Beauv.). Most varieties are yellow, due to the accumulation of carotenoids. However, there are some foxtail millet germplasms producing dark green millet. To elucidate the molecular mechanism of the chlorophyll retention phenotype, Daqinggu with green millet colour and Jingu 21 with yellow millet colour were selected as research material in this study. The total carotenoid level in dehulled millet of Daqinggu was about 0.024 mg/g, and 0.038 mg/g in Jingu 21. The transcript levels of carotenoid structural genes were investigated at three stages of grain development in both millet varieties. The expression levels of carotenoid biosysnthesis-related genes SiPSY3, SiPDS, SiZ-ISO, SiLCYB and SiCYP97C were significantly higher in Daqinggu than in Jingu 21, which was not consistent with the difference in the carotenoid levels between these two varieties. Interestingly, SiSGR, a homologue to the STAY-GREEN gene in Arabidopsis, tomato, and rice, was constitutively down-regulated during maturation in Daqinggu. In addition, the total chlorophyll content was consistently higher in Daqinggu than in Jingu21 during grain maturation. These evidences suggest that SiSGR is a key gene in regulating chlorophyll retention for dark green foxtail millet.