University of Dayton View Institution's Website 2 articles published in JoVE Biology Quantitative Comparison of cis-Regulatory Element (CRE) Activities in Transgenic Drosophila melanogaster William A. Rogers1, Thomas M. Williams2 1Department of Biology, University of Dayton, 2Department of Biology, Center for Tissue Regeneration and Engineering at Dayton, University of Dayton Phenotypic variation for traits can result from mutations in cis-regulatory element (CRE) sequences that control gene expression patterns. Methods derived for use in Drosophila melanogaster can quantitatively compare the levels of spatial and temporal patterns of gene expression mediated by modified or naturally occurring CRE variants. Biology A System for Culturing Iris Pigment Epithelial Cells to Study Lens Regeneration in Newt Rital B. Bhavsar*1, Kenta Nakamura*1, Panagiotis A. Tsonis1,2 1Department of Biology, University of Dayton, 2Center for Tissue Regeneration and Engineering, University of Dayton In newt, the lens regenerates always from the dorsal iris by transdifferentiation of the iris pigmented epithelial cells (IPEs). Here we describe a procedure to culture dorsal and ventral newt IPE cells and their implantation to the newt eye. The implanted cells are then studied by tissue sectioning and immunohistochemistry.