Girke T, Todd J, Ruuska S, White J, Benning C, Ohlrogge J
Department of Botany and Plant Pathology, Michigan State University, East Lansing, Michigan 48824, USA.
Plant Physiol. 2000 Dec;124(4):1570-81. doi: 10.1104/pp.124.4.1570.
To provide a broad analysis of gene expression in developing Arabidopsis seeds, microarrays have been produced that display approximately 2,600 seed-expressed genes. DNA for genes spotted on the arrays were selected from >10,000 clones partially sequenced from a cDNA library of developing seeds. Based on a series of controls, sensitivity of the arrays was estimated at one to two copies of mRNA per cell and cross hybridization was estimated to occur if closely related genes have >70% to 80% sequence identity. These arrays have been hybridized in a series of experiments with probes derived from seeds, leaves, and roots of Arabidopsis. Analysis of expression ratios between the different tissues has allowed the tissue-specific expression patterns of many hundreds of genes to be described for the first time. Approximately 25% of the 2, 600 genes were expressed at ratios > or =2-fold higher in seeds than leaves or roots and 10% at ratios > or =10. Included in this list are a large number of proteins of unknown function, and potential regulatory factors such as protein kinases, phosphatases, and transcription factors. The Arabidopsis arrays were also found to be useful for transcriptional profiling of mRNA isolated from developing oilseed rape (Brassica napus) seeds and expression patterns correlated well between the two species.
为了对拟南芥发育种子中的基因表达进行广泛分析，已制作了显示约2600个种子表达基因的微阵列。阵列上点样基因的DNA是从发育种子的cDNA文库中部分测序的10000多个克隆中挑选出来的。基于一系列对照，估计该阵列的灵敏度为每个细胞一到两个mRNA拷贝，并且如果密切相关的基因具有70%至80%以上的序列同一性，则估计会发生交叉杂交。这些阵列已在一系列实验中与来自拟南芥种子、叶片和根的探针进行杂交。对不同组织之间表达比率的分析首次使得数百个基因的组织特异性表达模式得以描述。在这2600个基因中，约25%在种子中的表达比率比在叶片或根中高2倍或更高，10%的表达比率比在叶片或根中高10倍或更高。该列表中包括大量功能未知的蛋白质以及潜在的调控因子，如蛋白激酶、磷酸酶和转录因子。还发现拟南芥阵列可用于对从发育中的油菜种子中分离的mRNA进行转录谱分析，并且两个物种之间的表达模式相关性良好。
