Morphology and protein expression of Symbiodinium in environmental stress

• Main Authors: Li-Chi Weng, 翁麗淇
• Other Authors: Pei-Luen Jiang
• Format: Others
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/66259812204768748807

碩士 === 國立東華大學 === 海洋生物科技研究所 === 103 === The stability of cnidarian-dinoflagellate (genus Symbiodinium spp.) endosymbioses depends on the regulation of nutrient transport between Symbiodinium populations and their hosts. Previously, we successfully induced the production of lipid droplets in the free-living cultured Symbiodinium (clade B) by depriving the cells of nitrogen for 5 days. The present study was therefore aimed at understanding the disruption of the endosymbiotic relationship between the cnidarians and dinoflagellates by nitrogen limitation using Aiptasia pulchella as an example. Transmission electron micrographs showed nitrogen deprivation-induced formation of lipid droplets, and lipid analyses further showed that polyunsaturated fatty acids were drastically enriched in Symbiodinium after 30 days of nitrogen limitation, although these were unaffected after 5 days of nitrogen starvation. The present study also suggested that the host provided nitrogen to the symbiotic cells during short-term environmental stress. However, the relationship started to deteriorate after 30 days. These findings provide a more details understanding of the mechanisms of the symbiotic relationship between a nitrogen resource and symbiotic dinoflagellates and might help explain the regulatory mechanism underlying endosymbiotic associations.