A specific glycerol kinase induces rapid cold hardening of the diamondback moth, Plutella xylostella

作者：Park Youngjin; Kim Yonggyun^*

来源：Journal of Insect Physiology, 2014, 67: 56-63.

DOI：10.1016/j.jinsphys.2014.06.010

• Rapid cold hardening
• Glycerol kinase
• Plutella xylostella
• Glycerol
• Supercooling point

Insects in temperate zones survive low temperatures by migrating or tolerating the cold. The diamond-back moth, Plutella xylostella, is a serious insect pest on cabbage and other cruciferous crops worldwide. We showed that P. xylostella became cold-tolerant by expressing rapid cold hardiness (RCH) in response to a brief exposure to moderately low temperature (4 degrees C) for 7 h along with glycerol accumulation in hemolymph. Glycerol played a crucial role in the cold-hardening process because exogenously supplying glycerol significantly increased the cold tolerance of P. xylostella larvae without cold acclimation. To determine the genetic factor(s) responsible for RCH and the increase of glycerol, four glycerol kinases (GKs), and glycerol-3-phosphate dehydrogenase (PxGPDH) were predicted from the whole P. xylostella genome and analyzed for their function associated with glycerol biosynthesis. All predicted genes were expressed, but differed in their expression during different developmental stages and in different tissues. Expression of the predicted genes was individually suppressed by RNA interference (RNAi) using double-stranded RNAs specific to target genes. RNAi of PxGPDH expression significantly suppressed RCH and glycerol accumulation. Only PxGK1 among the four GKs was responsible for RCH and glycerol accumulation. Furthermore, PxGK1 expression was significantly enhanced during RCH. These results indicate that a specific GK, the terminal enzyme to.

• 出版日期2014-8