Overview

The research interests of Wheeler Laboratory focus on understanding the molecular and cellular mechanisms involved in the development differentiated function in ovarian and embryonic cells. We use swine, cattle, and mice as model systems. Using transgenic animal technology, we are examining: (1) methods to increase the efficiency of production of transgenic animals, (2) vector systems which would allow tissue specific expression of 'foreign' genes in the transgenic genome, and (3) development and characterization of gene expression in embryonic stem cells. Currently, I am studying the molecular and cellular mechanisms of differentiation during early embryonic development. This has allowed development of an elegant system for embryonic differentiation using embryonic stem (ES) cells derived from swine embryos. We have used this system to produce the first chimeric pigs. We are examining signals which initiate differentiation in ES cells and characterization of the first genes that are expressed during this differentiation. In addition, we are studying the fate (fate mapping) of ES cells as they are incorporated into differentiated tissues of the embryo and fetus. Studies are being conducted to determine the feasibility of utilizing swine ES cell nuclei in nuclear transfer or cloning technologies. Finally, vector systems which would allow tissue specific expression of 'foreign' genes in the transgenic genome, specifically into reproductive tissues including milk, are being studied.