Abstract
Male gametophyte from angiosperm (pollen) is composed of three haploid cells that are single vegetative cell and two enclosed sperm cells. The drastic degradation of organellar DNA is known to occur between the bi-cellular and tri-cellular stages of pollen maturation. This degradation process is easily visualized by staining with a DNA-specific fluorescent dye, DAPI. However, the underlying molecular mechanism for the organellar DNA degradation is not known so far. We focused on the pollen maturation process and performed the screening for mutants defective in organellar DNA degradation. We isolated dpd1 (defective in pollen organellar DNA degradation) mutant in which DAPI-stained signals were observed in the cytoplasm of vegetative cells. Such signals were not observed in wild-type pollen grains. We will report the phenotypic analysis of dpd1 mutant and the functional analysis of the responsible gene.
