CLONING AND EXPRESSIONPATTERN OF HEAT SHOCKPROTEIN GENES FROM THEENDOPARASITOID WASP,Pteromalus puparum INRESPONSE TO ENVIRONMENTALSTRESSES

摘要

Six heat shock protein (HSP) genes from five HSP families in the parasitoid, Pteromalus puparum, were evaluated for their response to temperature (15 - 3°C , and 30 - 42°C for 1 h), heavy metals (0.5 - 5 mM Cd2+ and Cu2+ for 24 h and 60 h), and starvation (24 h). Compared with other insect HSPs, all conserved motifs are found in P. puparumHSPs, and they are very similar to those of the recently sequenced ectoparasitoid Nasonia vitripennis. The temporal gene expression patterns indicated that thesesix HSP genes were all heat-inducible, of which hsp40 was the most inducible. The temperatures for maximal HSP induction at high and low temperature zone were 36 or 39°C and 3°C, respectively. In the hot zone, all HSP genes have the same initial temperature (33°C) for up-regulation. Low concentrations of Cd2+ for a short-term promoted the expression of all HSP genes, but not high concentrations or long-term treatments. Cu2+ stress for 24 h increased expression of nearly all HSP. Four HSP genes changed after starvation. We infer that all six HSP genes are sensitive to heat. This may help understand the absence of P. puparum during the summer and winter. The expression profiles of six HSP genes in P. puparum under heavy metal stress indicates that HSPis a short-term response to cellular distress or injury induced by Cd2+ and Cu2+.