Welcome to the Tallquist Lab Website in the Department of Molecular Biology at UT Southwestern Medical Center at Dallas

The orchestration of cell movement, proliferation and differentiation in a developing embryo is an amazing accomplishment. Many different biochemical signals must be sent and received at the appropriate time and location to guarantee healthy progeny. Our lab is interested in understanding how these signals manifest themselves, and the model organism we use is the mouse. Primarily, we have focused on a family of receptor tyrosine kinases (the platelet derived growth factor receptors, PDGFRalpha and PDGFRbeta) that play important roles in both mammalian development and disease.

By using the mouse as a model system we are able to apply the tools of genetics, biochemistry, and embryology to unravel the key signaling molecules in development. Understanding these principles will enable us to define the pathways that become disrupted in human birth defects and disease.

When a cell undergoes an epithelial to mesenchymal transition, a diverse range of signaling, transcriptional, and cytoskeletal changes occur. Although EMT has been studied very extensively in gastrulation, neural crest cells, cardiac valve formation, and cancer, little is known about this process in the epicardium of the heart. The goal of this project is to elucidate the key signaling and transcriptional changes that occur in this tissue.

During development the epicardium of the heart undergoes a dynamic process of differentiation to give rise to cardiac fibroblasts and coronary vascular smooth muscle cells. Because minimal data is available regarding the formation of these cell types we will explore how this cell fate determination occurs. This information will be beneficial not only for understanding the development of these cells but could also provide us with information that could be used to manipulate these cells during adult disease processes such as fibrosis.

In addition to studying the function of the PDGF receptors, our lab is also investigating the roles of other genes in epicardial development. These genes include, Numb, Nf1, capsulin, and Wnt9b. Because many of these genes are expressed in a broad range of cells, we are generating tissue specific deletions of these genes to study their unique role within the epicardium.

There are currently two rotation projects available within the lab.

Rotation project 1-The goal of this project is to identify transcription factors that control the unique expression of the PDGF receptors within epicardial derivatives.

Rotation project 2-The goal of this project is to discover the requirement for PDGF receptor signaling in mesenchymal stem cells that give rise to adipose tissue.