Biological Sciences (61) The advent of inexpensive digital video technology has revolutionized the ability to capture images of cell structure and behavior through the microscope. In parallel, the fluorescent protein revolution, initiated with the cloning of GFP, has given researchers dramatic insights into the dynamics of proteins in living cells. This project capitalizes on these advances to give students in biochemistry, cell biology and genetics courses the opportunity to engage in self-directed laboratory exploration of cellular processes by using green fluorescent probes to compare processes in live cells of mutant and wild strains of the social amoeba Dictyostelium. Equipment added to the laboratory includes several low-cost video fluorescent microscope workstations, a spinning disc confocal microscope system, and an electroporator (for the genetics and cell biology labs). The modules being developed are based on current research at the institution and experience gained within the institution's core microscopy facility.
The intellectual merits of this proposal stem from extensive use of live cell imaging, the emphasis on quantitative digital imaging, and the investigative nature of the course. Students learn what a phase contrast optical system does and how it differs from Differential Interference Contrast, how fluorescence filter sets work and the relationship of a CCD chip to an image on a computer screen. The microscope is used for a variety of activities including: checking cultures, titering cells on a hemocytometer, and time-lapse video movie acquisition. Another key aspect of the course is quantitative imaging. Students learn about digital image processing including quantification of parameters like cell size, cell speed, and persistence of chemotactic movement using the power of the video microscope as a quantitative measurement instrument, rather than a qualitative photographic device. In most experiments, students not only investigate a cellular process, but they compare wild-type cells with mutants. The students are given guidelines, but not protocols and are encouraged to devise their own experimental questions within the general parameters of the laboratory. Each laboratory report is written as a mini-research manuscript in which they describe the background, assumptions and hypotheses, as well as the results and discussion.
The implementation of this proposal is having a broad impact on undergraduate education. The equipment is being utilized not only to enhance the core microscopy course, but also by two other laboratory courses in the department, using course suitable inquiry based fluorescence microscopy experiments designed jointly by the PI and the faculty responsible for the course. In addition, modified versions of the laboratory modules are being used in undergraduate summer programs, high schools, and community colleges. To reach the wider audience of Cell Biology faculty, the modules are being distributed to the Dictyostelium community through Dictybase, ASCB Education, BiosciEdNet and other teaching resources.
