玉米种子发育过程中Dad1基因的表达(英文)

Dad1是一个高度保守的细胞程序性死亡抑制基因。以拟南芥Dad1 (AtDad1) cDNA为模板,利用体外RT-PCR对其进行地高辛标记。以产物反义RNA作探针 (顺义RNA为对照),对Dad1在玉米种子发育过程中的时空表达图谱进行了研究。结果表明Dad1在一些衰老组织如子房壁、珠被(Fig.1, B&C)、成熟的胚乳 (Fig.1, E) 以及脱落的根冠细胞 (Fig.2 A)中表达量均较高,同时在新陈代谢活跃的组织如根尖分生组织细胞 (Fig.2, A&B)、发育的子叶(Fig.2, C&D)、雌性生殖细胞 (Fig.1 C)以及发育的胚乳细胞(Fig.1 C)中表达量也较高。结论:同其它植物中的Dad1同源基因一样,玉米中的Dad1基因在胚胎发育及胚乳PCD等多种发育过程中也可能起重要作用。

Expression of Dad1 in Maize Seed Development

Dad1 is a highly conserved programmed cell death (PCD) suppressor gene. Using digoxigenin-labeled anti-sense RNA probe, the expression of Dad1 cDNA in Arabidopsis was detected in developing maize seed tissues, including ovary, endosperm and embryo. Our results of in situ hybridization revealed that Dad1 was expressed in degenerating tissues, such as the ovary wall, the integument (Fig.1 B&C), the mature endosperm (Fig.1 E) and the root cap (Fig.2 A), as well as in some vigorously metabolizing cells such as the meristematic cells of root tip (Fig.2 A&B), the cotyledon cells (Fig.2 C&D), the female germ cells (Fig.1 C) and the dividing endosperm cells (Fig.1 C) in a temporal and spatial manner. These results show that, as other Dad1 homologs, maize Dad1 may also play a role in maize embryo development and in PCD during endosperm degeneration.