Transcriptome Characterization and Single Nucleotide Polymorphism (SNP) Identification in Vicia amurensis Oett. Using Next-Generation Sequencing Technology

Vicia amurensis is a perennial plant found in Northern China, Japan, and Korea that plays an important role in sustainable agricultural practices due to its ability to fix atmospheric nitrogen in a symbiotic association with rhizobia. 454 sequencing technology was used to sequence the V. amurensis transcriptome which yielded 26.41 Mb from 71,197 reads as a result of 24,959 valid singletons. In addition, 1743 contigs, with the largest contig size being 3534, and 26,702 unigenes were detected. The contig distributions in three non-mutually exclusive Gene Ontology classifications and clusters of orthologous gene classes showed that differentially expressed genes were generally overrepresented in general function and prediction alone (176, 14.47%), and posttranslational modifications, protein turnover, chaperones (162, 13.32%). In total, 12,656 single nucleotide polymorphism (SNP) types were detected; these variants contained 10,585 SNPs, 1513 indels and 558 variants involving more than one nucleotide. The 2383 SNP types with high confidence differences were identified. The present study provides invaluable information on the functional genomic resources and future biological research on V. amurensis. The SNPs identified in this study will provide a material basis for future mapping and marker-assisted breeding analyses.