31 - Characterizing the Transcriptional Regulation of Mef2a in Skeletal Muscle
Muscular dystrophy describes a group of diseases characterized by skeletal muscle degeneration. There are currently no effective treatments for the various forms of muscular dystrophy -- the main form of €treatment€ comprises mainly of aiding patients in controlling the symptoms that accompany their disease. A promising approach in the treatment of muscular disorders involves repairing or replacing diseased muscle with healthy muscle by way of regeneration. Skeletal muscle is one of the few mammalian tissues that has the capacity to regenerate from muscle stem cells residing in proximity to mature muscle fibers. While many strides have been made identifying pathways that regulate muscle regeneration, our understanding of this process is far from complete. Recently, it has been established that a key protein in the regulation of skeletal muscle regeneration is the MEF2A transcription factor, a protein that controls expression of genes essential for proper muscle function. Given the importance of MEF2A in the process of skeletal muscle regeneration, it is essential to understand the mechanisms by which this factor is regulated, as this information will likely provide insight into the molecular control of muscle regeneration. Thus, this research project focuses on identifying the transcriptional control regions of Mef2a responsible for promoting its expression in skeletal muscle regeneration. In uncovering the upstream signaling pathways of Mef2a, we may be able to provide new knowledge about the mechanisms through which regeneration occurs. Ultimately, this new insight may bring about more advanced forms of treatment for patients with muscular diseases.disease is always fatal unless treated and drugs used to treat the disease are toxic and associated with resistance. Therefore, it is important to study the biology of the parasite to find therapies that are more effective and less toxic. T. brucei actively move to invade host tissues, including the central nervous system. In order to exit the blood, the parasites burrow through the capillary walls. Motility is therefore believed to play a critical role in pathogenesis. The recent identification of two point mutations in the dynein subunit LC1 has made it possible to directly investigate the role of trypanosome motility in disease pathogenesis using viable motility mutants for the first time. However it is not known if these mutations are dominant negative. To test if LC1 point mutations are dominant negative and can disrupt parasite motility, knock in plasmids containing the mutant gene flanked by a drug marker were introduced into T. brucei and through homologous recombination replaced endogenous LC1 on one chromosome while leaving the other, wild type, unchanged. Mutant protein expression was confirmed using western blot analysis, and motility assays show that the mutation caused defective motility. These studies will ultimately provide insight into parasite motility and pathogenesis mechanisms.