Cloning and sequence analysis of squalene synthase gene and cDNA in Glycyrrhiza uralensis

Abstract

To clone and sequence the open reading frame and genomic sequence of squalene synthase (SQS) from Glycyrrhiza uralensis. The primers were designed according to cDNA sequence of SQS from G. glabra reported by Hiroaki HAYASHI, SQS cDNA was cloned with total RNA extracted from roots of G. uralensis. Specific fragments were amplified by RT-PCR and then were cloned and sequenced. SQS DNA was cloned with total DNA extracted from roots of G. uralensis. Specific fragments were amplified by PCR and then were cloned and sequenced. GuSQS1 (GenBank accession number: GQ266154) was 1 242 bp in length encoding proteins with 412 amino acid. NCBI Blast x search results showed GuSQS1 had the highest amino acid similarity to the corresponding proteins from G. uralensis. The identities of GuSQS1 with the two proteins were 98. 55% and 88. 62%. SQS (GenBank accession number: GQ180932) gene with 4 484 bp containing 13 exons and 12 introns was then amplified by PCR with genomic DNA extracted from roots of G. uralensis. These findings of cloning and sequencing the open reading frame and genomic sequence of squalene synthase (SQS) from G. uralensis brought some new clues for the further exploration of SmSQS function in sterol and terpenes biosynthesis.