Expressed sequence tags from rhizomes of Glycyrrhiza uralensis

Glycyrrhiza uralensis (Leguminosae, Fabaceae) is the most important medicinal plant used as a natural sweetener, in Chinese herbal medicines, and as a tobacco flavoring agent. Here, we report the generation of 56,857 expressed sequence tags (ESTs) derived from two full-length cDNA libraries produced from rhizomes (stolons) of two strains of G. uralensis, together with differential expression data obtained by Megasort analysis. The Megasort analysis was performed using two plant organs, namely, thickened roots and a rhizome-like organ, which differed in their glycyrrhizin content. After clustering of the 5 -end of ESTs, 5,542 contigs and 4,932 singletons were generated. A total of 10,474 nonredundant sequences were annotated on the basis of the TAIR database, of which 7,905 (75.5%) sequences exhibited homology to the sequences of registered genes. The gene functions of these 7,905 sequences were classified into Biological Process and Molecular Function on the basis of Gene Ontology (GO).