My long-term goal is to establish myself as an independent scientist at a top-tier research institution studying the gene regulatory networks (GRNs) that regulate cell morphogenetic movements during development and cancer. Towards this end, the proposed research advances my training in functional genomics and systems biology approaches that complement my previous research in cellular and developmental biology techniques. GRNs encompass both the physical and regulatory relationships amongst transcription factors (TFs) and between TFs and their target genes that drive specific cell biological processes. Despite their importance in regulating cell invasive behavior, the TFs and the identity of their downstream targets that specify invasiveness is largely unknown. Cell invasion through basement membrane (BM) serves as a mechanism underlying cell dispersal and organ formation during normal development, immune surveillance, and is mis-regulated during cancer metastasis. The Sherwood laboratory at Duke University has established a simple in vivo model that uniquely combines powerful genetic, functional genomic, and single cell visual analyses of anchor cell (AC) invasion through BM into the vulval epithelium during C. elegans larval development. Our current understanding of AC invasion includes the identification of three TFs and a handful of putative downstream targets that regulate both the establishment of a specialized invasive membrane and the ability of the AC to remove BM during invasion. The proposed experiments during the mentored phase of the award will begin to characterize the GRNs underlying cell invasion through BM by 1) identifying the binding partner of the bZIP oncogene TF, fos-1a, and the identity of FOS-1A binding sites within the C. elegans genome;and 2) identifying additional TFs that regulate AC invasion and testing whether they show conserved functions in regulating carcinoma cell invasion in vitro. Training in functional genomic techniques and systems biology approaches will be accelerated through advanced course work, attendance at national conferences, a collaboration with Dr. Marian Walhout's laboratory (University of Massachusetts Medical School), and co-mentorship by Dr. Philip Benfey, the director of Duke University's Systems Biology group and the Institute for Genome Sciences and Policy (IGSP). Training in human cancer in vitro assays will be carried out in the laboratory of Dr. Stephen Weiss (University of Michigan). These training experiences and the data acquired during the mentored phase will provide the basis to launch an independent research career. The research proposed in the unmentored phase of the award includes 1) characterizing the genomic regulatory regions that contain TF-binding sites that control gene expression in the AC during invasion and 2) determining the core complement of TFs that are both necessary and sufficient to recapitulate an invasion program in normal development and in human cancer invasion.
Cell invasion is not only a fundamental cell biological process during times of normal development (e.g., blood vessel growth and pregnancy), but is the underlying mechanism driving the spread of metastatic cancer in humans. Determining the core genes involved in promoting cell invasion in both C. elegans and human cancer will allow for the identification of new therapeutic targets to halt the lethality associated with cancer.
|Matus, David Q; Chang, Emily; Makohon-Moore, Sasha C et al. (2014) Cell division and targeted cell cycle arrest opens and stabilizes basement membrane gaps. Nat Commun 5:4184|