Separated Transcriptomes of Male Gametophyte and Tapetum in Rice

In flowering plants, the male gametophyte, the pollen, develops in the anther. Complex patterns of gene expression in both the gametophytic and sporophytic tissues of the anther regulate this process. The gene expression profiles of the microspore/pollen and the sporophytic tapetum are of particular interest. In this study, a microarray technique combined with laser microdissection (44K LM-microarray) was developed and used to characterize separately the transcriptomes of the microspore/pollen and tapetum in rice. Expression profiles of 11 known tapetum specific-genes were consistent with previous reports. Based on the spatiotemporal expression patterns and gene ontology (GO) categories of anther-expressed genes, some noteworthy expression patterns are discussed in connection with various important biological events of anther development. The separated transcriptomes of rice microspore/pollen and tapetum were measured at the premeiosis, meiosis, tetrad, uninuclear, bicellular, and tricelluar stages by using laser microdissection (LM)-mediated microarray.

在显花植物中，雄配子体（male gametophyte）即花粉，于花药内发育。花药的配子体与孢子体组织中复杂的基因表达模式，共同调控这一发育进程。其中，小孢子/花粉与孢子体绒毡层的基因表达谱尤为受到关注。本研究开发了结合激光显微切割（laser microdissection）的微阵列（microarray）技术（44K激光显微切割微阵列，44K LM-microarray），分别对水稻中小孢子/花粉与绒毡层的转录组（transcriptome）进行表征分析。11个已报道的绒毡层特异性基因的表达谱与既往研究结果一致。基于花药表达基因的时空表达模式与基因本体论（GO）分类，本研究结合花药发育的各类重要生物学事件，对若干值得关注的表达模式进行了探讨。本研究通过激光显微切割（LM）介导的微阵列技术，在减数分裂前、减数分裂、四分体、单核、双核及三核时期，分别检测了水稻中小孢子/花粉与绒毡层的转录组。