Wu Weiren

[Genetic analysis and gene mapping of DDF1, a pleiotropic gene involving in both vegetable and reproductive growth in rice].

There are many pleiotropic genes playing key roles in regulating both vegetative growth and reproductive development in plants. A dwarf mutant of rice with deformed flowers, named as ddf1, was identified from indica rice breeding lines. Genetic analysis indicated that ddf1 was resulted from the recessive mutation of a single gene, temporarily named as DDF1. This result suggested that DDF1 is a pleiotropic gene, which controls both vegetative growth and reproductive development in rice. To map this gene, an F2 population was developed by crossing the ddf1 heterozygote with the tropical japonica rice variety DZ60. By means of bulked segregant analysis and small population-based linkage analysis using the published RM-series rice SSR markers, DDF1 was preliminarily mapped in a region between markers RM588 and RM587 on chromosome 6 with the genetic distances of 3.8 cM and 2.4 cM to the two markers, respectively. By developing new SSR markers in this interval according to the published rice genome sequence, we further mapped DDF1 in a 165 kb interval. The results will facilitate cloning of DDF1.

Identifying stress-related programmed celldeath improves research on plant resistance

Programmed cell death (PCD) is essential to the survival and evolution of plants. Recently, the advance in the technology of plant genetics, physiology, molecular and cytological biology supports the study on the phenomena and mechnisms of plant PCD. In respect of phenomena, the significant progress includes the classification of two distinguish types of plant PCD: vacuolar PCD and necrotic PCD. The outstanding progress in mechnisms includes the discovery of the structure of a proteinase family: metacaspases, along with their role in survival/death decision or cell-death type controlling.