For an animal to develop normally from a fertilized egg, many changes must occur; for example, cells adopt different identities and some migrate to new locations to fulfill their functions in the organism.  How does encoded genetic information control these events?  To examine this question, we are taking advantage of Drosophila melanogaster, the fruit fly, to identify essential genes that regulate cellular decisions.  The genes in flies are very similar to those in other organisms, so results from this study provide a framework for increased understanding of development in general.  One known pathway integral to developmental processes is called JAK/STAT signaling, which is also important in human development, immune response, and disease progression. 

We have identified and characterized the roles of several new genetic regulators of STAT signaling activity.  Through genetic analysis, molecular biology, and mathematical modeling, we have built a clearer picture of how this cell-cell communication system works.  In ovarian cells, we have shown that the identified regulators are important for initiating signaling, determining the optimal number of migratory cells, and allowing the cells to move correctly, which is necessary for successful egg development. We have also leveraged mathematical modeling to develop a system to explain how groups of cells organize themselves and coordinate their movements. In the testes, we found that several of the same regulators function to limit STAT signaling and thereby determine stem cell number. To start the signaling cascade, some ovarian cells release activating molecules outside of themselves, and these molecules are detected by nearby cells to turn on STAT activity.  We developed a new strategy to image egg chambers, and, interestingly, found that the initiation of signaling could be influenced by the contours of neighboring cells, which create sinks or pools of signaling molecules.  The findings were further supported through mathematical modeling, which led to the same conclusions.  This influence of contour is likely to arise in many tissues where extracellular signaling molecules act – thus, these findings have broader impact on biological research in other contexts.   

In addition to our scientific goals, we have been dedicated to broadening participation in research and improving STEM education.  Through the funded project, I have mentored multiple students in laboratory research, including 3 PhD students, several other graduate students, and 18 undergraduates, and have continued to partner with diversity programs at my university to broaden participation.  Through these efforts, we have provided research training to over 14 under-represented minorities at the undergraduate level, and one at the graduate level.  In addition, we utilize the model we built for an Undergraduate Bio-Mathematics program to foster interdisciplinary research and training.  Two Master’s degree students in mathematics participated in this project.  In the classroom, I have adopted additional active learning/teaching strategies provided to over 250 students per year, developed improved assessment tools, trained undergraduates and graduate students in scientific teaching, and coached colleagues in seeking best practices for teaching and learning through the Teacher-Scholars Faculty Learning Community at UMBC.  The researchers on this project and I participated in multiple outreach activities in local K-12 schools and public science events to increase public interest and understanding of the work of biologists.

Last Modified: 04/06/2017
Modified by: Michelle Starz-Gaiano