1. Department of Biology, Middle Tennessee State University, Murfreesboro, TN 32132, USA
2. Center for Quantitative Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
3. Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN 37203, USA
4. Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA
5. Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37240, USA