1 Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States.
2 Oak Ridge National Laboratory, The Center for Bioenergy Innovation, Oak Ridge, TN, United States.
3 Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV, United States.
4 School of Natural and Environmental Science, Newcastle University, Newcastle upon Tyne, United Kingdom.
5 Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture, Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing, China.