碩士 / 國立東華大學 / 海洋生物科技研究所 / 97 / During a stable symbiosis, the number of Symbiodinium sp. cells residing in a gastrodermal cell of Cnidaria is the same. However, the mechanism of how the cell proliferation of symbionts is regulated remains unclear. The cell proliferation of Symbiodinium sp. in symbiotic Aiptasia pulachella and the protein expression of its CDK A were investigated. In addition, the effects of various light conditions on the cell proliferation of cultured Symbiodinium sp. (both clades A and B1) as well as CDK A protein expression during various stages of cell cycles were examined. The results showed that the Symbiodinium sp. isolated from symbiotic Aiptasia pulachella, identified as clade B1, remained mostly at G1. The percentage of these cells entering G2/M was stable independent of time. Thus, the Symbiodinium sp. under stable symbiosis is rarely mitotic, and its CDK A expression remains the same under various photoperiods. Furthermore, the cell cycle of cultured Symbiodinium sp. (both clades A and B1) is approximately 24 hours in a 12L/12D photoperiod. Cells passed commitment point after photosynthesis with activated CDK A progressed to S phase and mitosis. For clade B1 of Symbiodinium sp., 50% of cells proliferated under white and blue lights; 23% proliferated under red light and none proliferated at dark. For clade A of Symbiodinium sp., cell proliferation was most significantly enhanced by blue light, less by white or red light and none proliferated at dark. The increase of cell proliferation is higher in clade B1 than in clade A, but clade A is more sensitive to blue light. Even though the activity of CDK A did not change significantly during various stages of cell cycle or under various light treatments (i.e. white, blue and red lights), the proliferation of Symbiodinium sp. was blocked by the inhibitor of CDK A added from G1 to S. Therefore, the phosphorylation of CDK A is critical for chromosome duplication of Symbiodinium sp.
| Identifer | oai:union.ndltd.org:TW/097NDHU5270017 |
| Date | January 2009 |
| Creators | Shu-Jyuan Li, 李淑娟 |
| Contributors | Li-Hsueh Wang, 王立雪 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 55 |
Page generated in 0.0016 seconds