Isolation and functional analysis of genes that regulate development and morphogenesis in rice.

本课题对水稻花和叶发育调控基因的分离和分析进行了研究。(1)dl基因座的突变导致花中心皮向雄蕊的同源转化和叶中脉的丧失。我们分析了dl突变体的表型和dl基因的空间表达模式，发现dl基因调控心皮的指定和中脉的形成。我们还发现了DL与B类MADS基因的拮抗相互作用。(2)从玉米和小麦中分离了DL同源基因，并对其空间表达模式进行了分析。结果表明，这两种植物中控制心皮发育和中脉形成的DL功能保守。(3)DL是Yabby基因家族的成员。我们从水稻中分离了7个Yabby基因，并分析了Yabby蛋白的结构特征。每个yabby基因的空间表达模式与拟南芥yabby基因的空间表达模式不同，表明水稻yabby基因的功能与拟南芥不同。(4)水稻on1突变体增加了花器官的数量。这种表型似乎是由花分生组织的扩大引起的。我们试图通过定位克隆的方法分离该基因，并发现了一个可能的FON1基因。

In this project, we studied on the isolation and analysis of genes that regulate flower and leaf development in rice.(1) The mutation occurred in the dl locus causes homeotic transformation of carpels into stamens in the flower and loss of midrib in the leaf. We analyzed phenotypes of the dl mutants and spatial expression patterns of the DL gene and revealed that DL regulates carpel specification and midrib formation. We also indicate that DL is antagonistically interacted with class B MADS genes.(2) We isolated the DL orthologs from maize and wheat and analyzed their spatial expression patterns. The result indicated that the DL functions controlling carpel specification and midrib formation are conserved in these two plants.(3) DL is a member of the YABBY gene family. We isolated seven YABBY genes from rice and analyzed structural features of YABBY proteins. Spatial expression patterns of each YABBY gene were distinct from those of the Arabidopsis YABBY genes, suggesting that the functions of rice YABBY genes are diversified from those of Arabidopsis.(4) The rice fon1 mutant have increased number of floral organs. This phenotype seems to be caused by an enlargement of floral meristem. We tried to isolate this gene by positional cloning and found a putative FON1 gene.