From Proteins to Muscles: looking at the Interaction Between the Protein Akirin and Simjoang

One of the most fundamental organs to form during the earliest stages of development is the heart. In the fruit fly (Drosophila melanogaster), many genes and proteins work together for the formation of a fully functioning heart. Because cardiac muscles and skeletal muscles share common features, it is possible that some of the genes and proteins that govern skeletal muscle development are also responsible for cardiac muscle formation. Earlier work in the Nowak lab found that akirin works with a chromosome remodeling complex called NuRD. It is hypothesized that the interaction between akirin with the NuRD complex is important for the initiation of muscle developmental pathways in the fruit fly. We are presently exploring whether a functional interaction exists between akirin and one of the subunits of the NuRD complex called Simjoang (simj). This project will investigate whether a mutation in Simj will have an effect on proper heart and skeletal muscle development. We used live confocal imaging to record heartbeat patterns in akirin and simj double heterozygous crosses. In addition we recorded heart beats from akirin and simj self-crosses. We further used immunohistochemistry to image skeletal muscle patterns of mutant embryos from each cross. We determined that cardiac function appears abnormal in akirin,+/+,simj double heterozygous mutant embryos. We further identified a number of skeletal muscle patterning defects in these embryos compared with wild-type sibling embryos. Taken together, these data strongly suggest a genetic interaction between akirin and simj during myogenesis