De Novo Assembly and Comparative Transcriptome Analysis of Orange-Fleshed Korean Sweetpotato in Response to Oxidative Stress

Oxidative stress, resulting from an imbalance in production and scavenging of reactive oxygen species (ROS), plays a challenging factor to regulate molecular and physiological response of cells to unfavorable. Among the various ROS, hydrogen peroxide (H₂O₂) has been recognized as not only a toxic molecule but also a critical signal molecule involved in gene expression. Sweetpotato (Ipomoea batatas) is known as a relatively agroecologically wide adaptable crop and it represents one of the most globally important root crops to be grown on marginal lands. Although sweetpotato is recognized as a comparatively environmental stress tolerant plant, the molecular mechanisms underlying this tolerance are not well defined. Therefore, in this study, for a better understanding of the molecular mechanisms of sweetpotato to cope with oxidative stress caused by various environmental stresses, we conducted comparative transcriptome analysis using high-throughput sequencing technology by Illumina paired-end (PE) RNA-sequencing of sweetpotato leaves (cv. Sinhwangmi, an orange fleshed Korean sweetpotato cultivar) under 100 mM H₂O₂ treatment for 1 and 12 hours (referred to as H1 and H12, respectively). These sequence reads were de novo assembled and annotated by Blast2GO and BLASTX. Furthermore, transcriptome differences were analyzed by differentially expressed genes (DEG) to identify H₂O₂ induced alteration of gene family.