磷酸根在生物體內扮演重要的化學分子，被利用於合成胞器外膜，同時也參與基因訊息的儲存。為了進一步了解磷酸根對於矽藻細胞功能與蛋白質調控的重要程度，本研究利用穩定同位素標定法加以修飾後，配合質譜蛋白質體基本定量方式進行研究。三角褐指藻(Phaeodactylum tricornutum)被認為是良好的模式生物，通常用於了解環境變化對於細胞反應的訊息，原因是其基因體已經完全解碼可以配合蛋白體從事研究。實驗中使用氮的穩定性同位素15N。並利用層析串連式質譜儀解析三角褐指藻的蛋白資訊。 Phosphorus plays decisive roles in living organism such as being the building block of cell membrane, and the genetic information storage. In order to investigate how phosphorus availability affects cellular functions at the protein level in diatoms, a modified stable isotope labeling by amino acids in cell culture (SILAC) method coupled with mass spectrometry based quantitative proteomics approach was performed in this study. Phaeodactylum tricornutum serves as a good model organism for understanding the environmental impact to cellular responses in diatoms because of the available comprehensive genomics and proteomics information. The stable isotope of nitrogen, 15N, was introduced in the culture medium as the nitrogen source for protein labeling. The protein profiles of Phaeodactylum tricornutum were evaluated by LC-MS/MS analysis.