所属 川崎医療福祉大学 医療福祉学部 臨床心理学科 職種 特任教授
|表題||Sponge cytogenetics:Mitotic chromosomes of ten species of freshwater sponge.|
略 称：Zool. Sci.
|著者・共著者||Ishijima Junko, Iwabe Naoyuki, Masuda Yoshiki, Watanabe Yoko, Matsuda Yoichi|
|概要||Porifera(sponges) are the most basal phylum of extant metazoabs. To gain insight into sponge genome construction, cytogenetic analysis was performed for ten species of six genera, using conventional Giemsa staining, chromosome banding, and fluorescence in-situ hybridization. The karyotypes were very similar among the ten species, exhibiting a diploid chromosome number of 2n=46 or 48, and usually consisted of microchromosomes with one or two pairs of large chromosomes. The 18S-28S rRNA genes were localized to a single pair of microchromosomes in two Ephydatia species. Hybridization signals of the telomere(TTAGGG)n sequences were observed at the ends of metaphase chromosomes. The genome sizes of Ephydatia fluviatilis and Ephydatia muelleri were estimated by flow cytomeric analysis as about 0.7pg per diploid complement. These freshwater sponge species appear to represent a fairly homogeneous group with respect to karyotypes.|