Plant Breeding & Production Division, Agricultural Research Institute, Hokuren Federation of Agricultural Cooperatives, Naganuma, Hokkaido, 0691317, Japan.
Plant Mol Biol. 2010 Jan;72(1-2):137-52. doi: 10.1007/s11103-009-9559-x. Epub 2009 Oct 23.
The control of seed germination under environmental conditions, where plants will be grown, is important for the adaptability of plants. Low-temperature is one of the most common environmental stress factors that affect plant growth and development and places a major limit on crop productivity in cultivated areas. Previously, qLTG3-1, a major quantitative trait locus controlling low-temperature tolerance at the germination stage in rice (called low-temperature germinability) was identified, which encodes a protein of unknown function. To identify genes targeted by qLTG3-1, a genome-wide expression profiling analysis using the 44 K Rice Oligo microarray was performed. Because the expression of qLTG3-1 was dramatically increased at 1 day after incubation, the expression profiles at this time were compared between Hayamasari, which has a loss-of-function qLTG3-1 allele, and a near isogenic line with a functional allele. A total of 4,587 genes showed significant differences between their expression levels in the two lines. Most of these genes might be involved in the process of seed germination itself, and then a focus was made on qLTG3-1 dependently induced or suppressed genes, defined as 'qLTG3-1 dependent' genes. Twenty-nine 'qLTG3-1 dependent' genes with diverse functions were categorized, implying that disruption of cellular homeostasis leads to a wide range of metabolic alterations and diverse cross-talk between various signaling pathways. In particular, genes involved in defense responses were up-regulated by qLTG3-1, indicating that qLTG3-1 expression is required for the expression of defense response genes in low-temperature germinability in rice.
在植物生长的环境条件下控制种子萌发对于植物的适应性很重要。低温是影响植物生长发育的最常见环境胁迫因素之一，对栽培区作物生产力有重大限制。先前，已经鉴定出控制水稻萌发阶段低温耐受性的一个主要数量性状位点 qLTG3-1（称为低温发芽性），该基因编码一个未知功能的蛋白质。为了鉴定 qLTG3-1 的靶基因，使用 44 K Rice Oligo 微阵列进行了全基因组表达谱分析。由于 qLTG3-1 的表达在孵育后 1 天显著增加，因此在此时比较了具有功能等位基因的 Hayamasari（具有功能 qLTG3-1 等位基因的近等基因系）和具有功能 qLTG3-1 等位基因的近等基因系之间的表达谱。共有 4587 个基因在这两个系之间的表达水平上存在显著差异。这些基因中的大多数可能参与种子萌发本身的过程，然后重点关注 qLTG3-1 依赖诱导或抑制的基因，定义为“qLTG3-1 依赖”基因。将具有多种功能的 29 个“qLTG3-1 依赖”基因进行了分类，这表明细胞内稳态的破坏导致广泛的代谢改变和各种信号通路之间的广泛串扰。特别是，与防御反应相关的基因被 qLTG3-1 上调，表明 qLTG3-1 表达是水稻低温发芽性中防御反应基因表达所必需的。
