Genetic dissection of the development of the inflorescences in Arabidospsis thaliana.

为了了解拟南芥花形态发生中的发育过程，本研究对拟南芥的erecta和acaulis基因的发育突变进行了分子遗传学分析。在去年的研究基础上，我们发现了ERECTA基因表达的重要顺式调控区，构建了带有顺式调控元件的uidA报告基因转基因植株，并利用原位技术对这些转基因植株的表达模式进行了分析，利用酵母表达系统对反式调控因子进行了分析。将用于调节表达的ERECTA-5'区与大肠杆菌lacZ基因融合，并将报告基因引入酵母细胞。将携带具有酵母启动子的植物cDNA的第二质粒引入具有ERECTA-lacZ报告基因的酵母细胞中。在筛选了3，000，000个菌落后，我们发现了11个表达报告基因的cDNA。其中一个克隆已被分离出来，并已被证明具有相同的表达特性和DNA转录因子的DNA同源性。我们的策略是基于图位的基因步移法分离ACAULIS 5基因。作为初始步骤，物理作图进一步扩展到5号染色体上（南）臂。我们使用P1噬菌体质粒中包含的DNA克隆鉴定重叠群。一个P1克隆体可能是命中的候选者。

The developmental mutations of Arabidopsis thaliana in erecta and acaulis5 have been analyzed molecular genetically in order to understand the developmental processes in the floral morphogenesis.At first, the ERECTA gene has been studied. From the studies carried out last year, we found the important cis-region for the expression of the ERECTA gene and constructed the transgenic plants expressing the reporter of the uidA gene with the cis-elements.We extented the analysis of these transgenic plants for the pattern of the expession using in situ techniques.For the analysis of trans-factors, we used yeast expression systems. The ERECTA-5' region for regulated expression was fused to the E.coli lacZ gene and the reporter was introduced into yeast cells. Second plasmids carrying plant cDNAs with yeast promoter were introduced into the yeast cells with the ERECTA-lacZ reporter. After screening 3,000,000 colonies, we found 11 cDNAs for the expression of the reporter. One clone was isolated and has been shown to have same expression-chacteristics and DNA homology to DNA-transcription factors.Secondly, we extended the study of acaulis5 mutations. Our strategy is the map-based gene walking for the isolation of the ACAULIS5 gene. As an initial stetp, physical mapping was further extended in the chromosome 5 upper (south) -arm. We idetified the contigs using DNA clones included in the P1 phage-plasmids. One P1 clone is the possible candidate for the hit.