Development and characterization of simple sequence repeat (SSR) markers based on a full-length cDNA library of Scutellaria baicalensis

• 6491 ESTs of S. baicalensis were obtained from a cDNA library.
• A total of 78 SSRs were identified from our UniGene sequences.
• SSR markers associated with the active ingredients of S. baicalensis were selected.

Scutellaria baicalensis Georgi is an herbaceous perennial plant used as one of the staple Chinese herbal medicines in China with a long officinal history. However, research on S. baicalensis is currently limited due to the lack of genome and gene expression information. A full-length cDNA library from leaves and roots of S. baicalensis subjected to water deficit and heat, conditions that have been shown to affect baicalein accumulation, was constructed. There were 6491 expressed sequence tags (ESTs) obtained. UniGenes were assembled by BLAST similarity searches and annotated with Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). A total of 78 simple sequence repeats (SSRs) were identified and SSR markers associated with the active ingredients of S. baicalensis were selected. EST-SSR transferability was determined from 5 populations from different areas. This study is the first to produce a large volume of gene expression data from S. baicalensis to facilitate gene discovery in S. baicalensis and provide an important resource for molecular genetic and functional genomic studies in this species.