Cytological Analyses in Melandrium album: Genome Size, Chromosome Size and Fluorescence in situ Hybridization
1994 年 59 巻 1 号 p. 135-141
詳細
1994 年 59 巻 1 号 p. 135-141
Melandrium album, a dioecious plant, has two sex chromosomes (X and Y). The haploid genome size of M. album was determined to be 4700 Mbp based on the amount of DNA in sperm nuclei in pollen by fluorimetry using a video-intensified microscope photon counting system (VIMPCS) after propidium iodide and 4', 6-diamidino-2-phenylindole staining. This value is about 33 times as much as that of Arabidopsis thaliana. The DNA content of each mitotic chromosome was also determined by VIMPCS. The size of the Y chromosome was 860 Mbp, which was 1.4 times as much as that of the X chromosome. Moreover, we visualized biotin-labeled 18S-5.8S-26S rRNA gene (large rRNA gene) probe and 5S rRNA gene probe in mitotic chromosomes by fluorescence in situ hybridization. Both of the rRNA genes were located on four pairs of autosomes, respectively. The sex chromosomes exhibited neither large rRNA genes nor 5S rRNA genes.
