This project seeks to identify universal mechanisms that organize specialized structures on the cell surface using the single-celled protozoan Tetrahymena thermophila. Structures studied include ones important for both feeding and excretion. Knowledge will be generated as to how newly synthesized cell-surface components are delivered to the proper location and in the proper abundance. This project will engage early career scientists (primarily undergraduates) in genetics, cell biology, and advanced microscopy through a combination of independent and course-based research experiences. This effort pilots a program to recruit students from under-represented backgrounds into mentored, collaborative research teams with long-term committed apprenticeships. Along the way, we will develop the ?Visible Cell?, a comprehensive teaching and research resource consisting of fluorescent cellular probes expressed in engineered cell-lines and made available to the broader research community. This collection will include cells that express fluorescently-tagged proteins spotlighting specific organelles, membrane systems, and cytoskeletal components which can be studied in both the laboratory and the classroom.
This research focuses on the Broadened Cortical Domain (BCD)1 gene, which when disabled, results in the assembly of multiple mouths and supernumerary excretory pores. Sequence analysis of this gene reveals that its product resembles a protein involved in membrane trafficking. Experiments are designed to test the hypothesis that the Bcd1 protein promotes endocytosis (retrieval of excess surface materials) through localized kinase activation. These experiments include pharmacological and genetic manipulation of membrane trafficking and cell signaling pathways to elucidate how homeostasis of these pathways leads to proper assembly of cell surface organelles. Finally, we will identify and characterize the gene that causes the janusA phenotype, a mirror-image duplication of the entire ventral organelle pattern. Together, these studies of BCD1 and janusA will provide understanding of mechanisms that determine both the localization and dimensions of major cell surface structures and global cell patterning.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
