Clone and expression of anthranilate synthase gene from Tolypocladium guangdongense under differential experimental conditions

Abstract:

[Background] Anthranilate synthase, one common enzyme in plants and microbes, is involved in the biosynthesis of tryptophan and auxin, and plays an important role in growth and development, together with the response to multiple stresses. Tolypocladium guangdongense is a new cordyceps resource only found in South China, and has a great exploitation value. [Objective] Dissect the gene features of TgtrpE, and explore the expression pattern of TgtrpE at differential developmental stages and temperature stress conditions in T. guangdongense. [Methods] The coding sequences of TgtrpE were cloned from T. guangdongense and used for bioinformatic and phylogenetic analysis. Real-time fluorescence quantitative PCR (RT-qPCR) was performed to analyze the expression pattern of TgtrpE under differential developmental stages and temperature stresses. [Results] The sizes of TgtrpE were 1 613 bp (DNA) and 1 563 bp (cDNA) in length, respectively. It encodes 521 amino acids with a molecular weight approximate of 56.86 kD. The phylogeny result showed that the TgTrpE protein of T. guangdongense was clustered into one clade with those of ascomycetes fungi, and had a higher similarity with Tolypocladium paradoxum and Tolypocladium capitatum. RT-qPCR results showed that compared to the mycelial stage, TgtrpE was significantly up-regulated at primordium and young fruiting body stages, whereas TgtrpE showed a clear downregulation expression at mature fruiting body stage and in the response process of cold and heat stresses. [Conclusion] TgtrpE may play an important role in the processes of primordium formation, fruiting body development and temperature stresses.