RUI: Physiological Ecology of Diatom Motility and Adhesion

Cohn9982897硅藻是一类数量丰富、分布广泛的金藻，是几乎所有水生群落中最重要的成员之一，通常为其他生物提供大部分初级生物量。由于硅藻位于食物链的底部，了解硅藻如何在其环境中成功，以及不同的环境条件如何影响其生存能力变得至关重要。这个项目旨在更好地了解硅藻在其环境中移动的方式，以及这种移动如何帮助它们(与其他藻类和不同硅藻物种之间)竞争有限的当地资源，如光和养分。由于这些细胞被限制在一个坚硬的玻璃状细胞壁中，它们的移动被认为是通过细胞壁上的特殊缝隙分泌粘液，以及随后施加在粘液链上的力所产生的。PI计划通过以下方式研究硅藻的运动过程：1)分析硅藻与下垫面形成的直接接触点的数量和分布，作为环境条件(光、温度等)变化的函数；2)分析硅藻在流水存在的情况下在不同环境条件下附着在表面的能力；以及3)分析环境条件对硅藻在光区聚集能力的影响。实验将在德保罗大学进行，这是一所以教学为导向的城市大学，研究团队包括几名本科生。本研究中使用的技术，如视频显微镜和干涉反射显微镜，使用各种滤光片和环境细胞室来调节光、温度、水和表面条件，相对容易让学生快速学会。因此，这个项目提供了一个机会，不仅可以增加我们对硅藻行为如何受到环境条件影响的知识，还可以为一些本科生提供一个令人兴奋的培训机会，让他们直接参与细胞和环境研究。

Cohn9982897Diatoms, an abundant and widespread group of golden algae, are one of the most important members of virtually all aquatic communities, often providing much of the primary production of biomass for other organisms. With diatoms situated at the base of the food chains, it becomes critical to understand how diatoms succeed in their environments, and how different environmental conditions affect their viability. This project is designed to better understand the way in which diatoms are able to move through their environment, and how this movement helps them compete (both with other algae and between different diatom species) for limited local resources such as light and nutrients. Because these cells are confined within a hardened glass-like cell wall, their movement is thought to be generated by the secretion of mucilage through specialized slits in their cell wall, and the subsequent force exerted on the adhering mucilage strands. The PI plans to examine the process of diatom movement by: 1) analyzing the number and distribution of direct contact sites made by diatoms with the underlying surface as a function of changes in the environmental conditions (light, temperature, etc.); 2) analyzing the ability of diatoms to adhere to surfaces under different environmental conditions in the presence of flowing water; and 3) analyzing the effect of environmental conditions on the ability of diatoms to aggregate in areas of light. The experiments will be carried out at DePaul University, a teaching-oriented urban university, with a research team that includes several undergraduates. The techniques used in this study, such as video-microscopy and interference reflection microscopy, using various filters and environmental cell chambers to regulate the light, temperature, water, and surface conditions, are relatively easy for students to learn quickly. This project therefore provides an opportunity to not only increase our knowledge of how the behavior of diatoms is affected by the environmental conditions, but also offer an exciting training opportunity for a number of undergraduate students to get involved directly in cellular and environmental research.