Expression Patterns of Three Genes Under Short and Long Term Cold Exposure in Thitarodes pui (Lepidoptera: Hepialidae), A Host of Ophiocordyceps sinensis.

From the paper

Abstract

UNLABELLED: BACKGROUND: Thitarodes larvae are the host of the caterpillar fungus Ophiocordyceps sinensis. Low temperature is the main environmental limitation for larvae growth.

OBJECTIVE: To better understand the cold adaption process in T. pui larvae, the expression patterns of trehalose-6-phosphate synthase (TpTPS), heat shock protein 70 (TpHSP70), and heat shock protein 90 (TpHSP90) were investigated upon short and long-term exposure to 0°C.

MATERIALS AND METHODS: The 6th instar T. pui larvae were collected in July 2013. TpTPS was firstly sequenced and expression patterns of TpTPS, TpHSP70 and TpHSP90 were investigated using quantitative PCR.

RESULTS: Full-length cDNA of TpTPS was 3,012 bp, with an open reading frame of 2,472 bp and an encoding protein of 823 amino acids. TpTPS up-regulation was induced by cold exposure. TpHSP70 expression is altered by cold exposure, but remained low. TpHSP90 expression was obviously up regulated in long-term cold stimulation.

CONCLUSION: All three genes (TpTPS, TpHSP70 and TpHSP90) have likely contributed to cold tolerance in T. pui larvae, TpTPS and TpHSP90 potentially being more important.