In Vivo Molecular-Level Investigation of Cellular Activities of Fission Yeast Using Raman Microspectroscopy and Imaging

• Main Authors: Chiu, Yu-fang, 邱郁芳
• Other Authors: 重藤真介
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/90532731025404791508

碩士 === 國立交通大學 === 應用化學系碩博士班 === 99 === A number of physiological parameters and conditions profoundly influence the bioactivity of cells in various ways. Here, among these parameters and conditions, we investigated the effects of growth temperature and phase of the growth curve on the cellular activities of Schizosaccharomyces pombe by using Raman microspectroscopy and imaging, in vivo and at the molecular level. First, in the study of the temperature effects on yeast Raman spectra, we focus on the variation of the intensity of the band at 1602 cm−1, which is a Raman band that is highly relevant to metabolic activities of the yeast cells. The result shows that at ~32 °C, the intensity of the 1602 cm−1 band begins to decrease gradually by approximately 45% and seems to reach a plateau above ~ 35 °C. This decrease in the 1602 cm−1 band intensity is indicative of lowered metabolic activity of the yeast cells at such high temperatures. Second, Raman imaging was performed on S. pombe cells in different growth phases, i.e., log and stationary phases, in order to examine how these growth phases affect molecular compositions and distributions in S. pombe cells. The observed Raman images revealed that the distributions of phospholipids and proteins are usually localized at the two sides of yeast cells in the stationary phase, while in the log phase, they appear to be more uniformly distributed over the whole cell. We interpret the localization of lipids in the stationary phase in terms of substantial energy storage in some particular regions of S. pombe cells. Compared with the stationary phase, the produced proteins and phospholipids may be consumed immediately for DNA duplication and other events, there may be no need for them to be stored in a large amount in the log phase. As a result, the cells do not show lipid localization as evidently as those in the stationary phase.