Dong Jinzhuo, Keller Wilf A, Yan Wei, Georges Fawzy
Plant Biotechnology Institute, National Research Council Canada, 110 Gymnasium Place, S7N 7R9, Saskatoon, Saskatchewan, Canada.
Planta. 2004 Jan;218(3):483-91. doi: 10.1007/s00425-003-1124-2. Epub 2003 Oct 23.
Approximately 5000 plaques derived from a Brassica napus L. (canola) seed-cDNA library representing 15 days after pollination (DAP) were differentially screened for highly expressed genes at the early stages of seed development. Analysis of 104 differentially expressed sequence tags revealed 54 unique genes, of which 33 had putative homologues described in Arabidopsis thaliana (L.) Heynh. or B. napus. These encoded diverse proteins, ranging from proteins of unknown function to metabolic enzymes and proteins associated with cell structure and development. Twenty-five genes were only expressed in seeds, and 11 of these started to express as early as 5 or 10 DAP. The majority of the seed-specific genes that are expressed at early stages of seed development encoded proteins with high similarity to hypothetical Arabidopsis proteins. Tissue-specificity determined by Northern analysis revealed that four seed-specific genes were expressed only in seed coats and another five in both embryos and seed coats. Analysis of transcript profiles of seed-abundant as well as seed-specific genes, and their expression patterns, implies that the B. napus seed is undergoing an active cell proliferation during 10-20 DAP, while establishing metabolic networks for subsequent seed maturation.
从授粉后15天的甘蓝型油菜种子cDNA文库中获取了约5000个噬菌斑，对种子发育早期高表达的基因进行了差异筛选。对104个差异表达序列标签的分析揭示了54个独特基因，其中33个在拟南芥或甘蓝型油菜中有假定的同源物。这些基因编码多种蛋白质，从功能未知的蛋白质到代谢酶以及与细胞结构和发育相关的蛋白质。25个基因仅在种子中表达，其中11个早在授粉后5天或10天就开始表达。在种子发育早期表达的大多数种子特异性基因编码的蛋白质与拟南芥假定蛋白质高度相似。通过Northern分析确定的组织特异性表明，四个种子特异性基因仅在种皮中表达，另外五个在胚和种皮中均有表达。对种子丰富基因以及种子特异性基因的转录谱及其表达模式的分析表明，甘蓝型油菜种子在授粉后10 - 20天经历活跃的细胞增殖，同时为随后的种子成熟建立代谢网络。
