Directed cell migration is critical in development and in numerous physiological processes in the adult such as wound healing and immune response. It also plays a critical role in pathological events like cancer metastasis. Our lab has been studying cell migration for over 40 years. As a supplement to our MIRA grant, we are requesting funds to purchase a Total Internal Reflection Fluorescence Microscope with superresolution capability. As described in the research plan this instrument is essential for imaging the many biosensors we use in our studies. The instrument we have available currently is 15 years old and lacks the modern technology that would greatly facilitate our studies. We neglected to consider the need for this instrument in the original application for renewal of the MIRA. The instrument is approximately $254337. I am requesting $200000 as a supplement to my MIRA grant. The Department of Cell Biology will provide institution support of $54337 (see letter from Dr. Ewald).