Role of Symbiotic Algae on Gemmule Germination of a Freshwater Sponge, Radiospongilla cerebellata

URI http://cur-ren.cjc.ac.jp/metadata/93
FulltextURL
Title
Role of Symbiotic Algae on Gemmule Germination of a Freshwater Sponge, Radiospongilla cerebellata
Author
著者 Okuda Naomi
著者(別表記) Okuda Naomi
著者 Yamamoto Atsuko
著者(別表記) Yamamoto Atsuko
著者 Satoh Yuriko
著者(別表記) Satoh Yuriko
著者 Fujimoto Yoshihiro
著者(別表記) Fujimoto Yoshihiro
著者 上島 孝久
著者(別表記) Kamishima Yoshihisa
Abstract

Annandale sponges (Radiospongilla cerebellata) have chlorellae as endosymbiotic algae and are distributed throughout the freshwaters of southwestern Japan. Gemmules of this sponge hatch only under an illuminated condition. The hatch is perfectly inhibited in total darkness. Although illumination is necessary for the gemmule hatching, the intensity of the light is very low and the illuminating period to induce the hatching is very short. Gemmules also fail to hatch unless the surface of incubating media is freely exposed to the atmosphere. Photosynthetic inhibitors strongly suppressed the hatching even under the optimal temperature and fully illuminated condition. To understand role of air components and photosynthesis on the gemmule hatch, we examined gaseous elements of the air and found that oxygen and carbon dioxide were responsible for the gemmule hatch. These gases are also evolved or consumed by photosynthesis. When oxygen was evacuated from the incubating media, no gemmules were hatched. On the other hand, gemmules incubated in a medium containing excess carbon dioxide did not germinate even under the optimal illuminated condition. This suggests that gemmule germination of the Annandale sponges seems to be initiated by oxygen and suppressed by carbon dioxide. This suggests that the both gasses might be evolved in or consumed from hibernating gemmule cells by photosynthesis of symbiotic algae to induce germination in these animal cells.

Subject
470 Botany
Keyword
Symbiosis
Sponge
Algae
Publish Date
2002
Publication Title
Chugokugakuen journal
Volume
1
Start Page
7
End Page
12
ISSN
1348-1452
NCID
AA11806612
Publisher
中国学園大学/中国短期大学
Copyright Holders
中国学園大学/中国短期大学
Official URL
Contents Type
Departmental Bulletin Paper
language
English
File Version
publisher