Influence of N, P, Fe Nutrients Availability on Nitrogen Metabolism-Relevant Genes Expression in Skeletonema marinoi

作     者：JING Xiaoli MI Tiezhu ZHEN Yu WANG Hualong YU Zhigang 

作者机构：College of Marine Life Science Ocean University of China Function Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Marine Environment and Ecology Ministry of Education College of Environmental Science and Engineering Ocean University of China Key Laboratory of Marine Chemical Theory and Technology Ministry of Education 

出 版 物：《Journal of Ocean University of China》 (中国海洋大学学报（英文版）)

年 卷 期：2019年第18卷第1期

页      面：239-252页

核心收录：

学科分类：07[理学] 

基　　金：supported by the National Natural Science Foundation of China (No. 41521064) the Scientific and Technological Innovation Project of the Qingdao National Laboratory for Marine Science and Technology (No. 2016ASKJ02) the Public Science and Technology Research Funds Projects of Ocean (No. 201205031) 

主　　题：Skeletonema marinoi nitrogen metabolism relative gene expression RT-qPCR 

摘      要：Nitrogen(N), Phosphorus(P), and Iron(Fe) are essential elements for cellular structure and metabolism. In addition to dissolved inorganic nitrogen(DIN), phytoplankton is able to utilize dissolved organic nitrogen(DON). There is general consensus that both bacteria and higher plants nitrogen metabolism is affected by phosphate availability; this was also found to be true in coccolithophorid. Iron affects the structure and function of ecosystems through its effects on nitrogen metabolism. However, it is unclear how these nutrients affect Skeletonema marinoi s nitrogen metabolism. Here, using RT-qPCR, we investigate effects of N, P, and Fe on S. marinoi s nitrogen metabolism and nitrate reductase activity. These results illuminate that in S. marinoi, various nutrients have direct regulation on these genes expression at the molecular level. The varying degree of responses for these genes expression with differing N sources may act to increase the efficiency of nutrient capture when nitrate is limited. Suitable gene expression occurs at a N/P ratio of 16, which represents the atomic N/P ratio of phytoplankton cells and N/P concentrations in ocean; thus, nitrogen metabolism gene expression should be regulated by the existing N/P ratios in the phytoplankton s internal and external environment. Fe concentration has a direct and significant effect on nitrogen metabolism by regulating gene expression and nitrate reductase activity. Gene expression profiles identified in S. marinoi provide a foundation for understanding molecular mechanisms behind diatom nitrogen metabolism with changing N, P, and Fe nutrients allowing a basic understanding of how diatom growth is affected by nutrient utilization.