@inproceedings{oai:jaxa.repo.nii.ac.jp:00013433,
 author = {清本, 正人 and 黒谷, 明美 and 江口, 星雄 and 山口, 守 and Kiyomoto, Masato and IzumiKurotani, Akemi and Eguchi, Hoshio and Yamaguchi, Mamoru},
 book = {宇宙利用シンポジウム　第24回　平成19年度, Space Utilization Research: Proceedings of the Twenty-fourth Space Utilization Symposium},
 month = {Mar},
 note = {Sea urchin and other echinoderm animals have calcitic endoskeleton. In sea urchin embryo, skeletogenesis starts at late gastrula stage and then the spicules grow up to larval skeletons. The skeletogenic cells are called primary mesenchyme cells derived from micromeres at 16-cell stage. We already reported a promotive effect of hypergravity on skeletogenesis in the 0.25 percent horse serum culture of the skeletogenic cells. In this condition, cultured skeletogenic cells are so sensitive that they show a clear difference of skeletogenesis under the hypergravity though it is difficult to detect significant difference in the culture medium containing 4 percent horse serum. In 0.25 percent serum, the number of spicule is less than that in 4 percent serum under 1 xg condition. It recovers to the similar level significantly even in 0.25 percent under hypergravity (100 xg). In this study, we examined the effect of hypergravity on the spicule formation of the sea urchin embryo. The embryos cultured under hypergravity showed some abnormal skeletogenesis. The elongation of two arm rods (post oral rod) was suppressed in 80 percent of embryos under 100 xg condition. Under 5 xg condition most of them developed into normal larvae, but additional branching, abnormal partial thickening and excess spicule formation were observed. It is considered that spicule formation in embryo is accepting not only direct hypergravity effect but also indirect effect via surrounding tissues. The excess spicule formation observed in the embryo is correspond to the increase of spicule in the culture experiment and supposed to be one direct effect of hyper gravity., 資料番号: AA0063706057},
 pages = {223--224},
 publisher = {宇宙航空研究開発機構宇宙科学研究本部, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)},
 title = {ウニの生物石灰化に対する重力環境の影響},
 year = {2008}
}