Effect Of Heat Treatment On The Survival Rate,Protective Enzyme And HSP70of2Kinds Of Color Patterns Of Tenebrio Molitor

As a kind of important economic insect, Tenebrio molitor is widely used in agriculture, medicine,and animal husbandry by its short generation cycle, strong living ability and lower cost to raise it. The ability of heat resistance is one of the important indexes for insect breeding. There is a close relationship between the ability of heat resistance of insect and the expression of heat shock protein or the activity of protective enzyme. The study on the difference of heat tolerance between yellow-pattern T.molitor and black-pattern T.molitor and the molecule mechanism of this difference provide reference for T.molitor breeding. This paper study the effect of heat treatment on survival rate of the larve,pupae and adult of T.molitor of2kinds of color patterns. And then, we study the effect of heat on HSPs and protective enzyme of T.molitor of2kinds of color patterns. The main result of this research is as follows.1. Larva and adult of T.molitor of2kinds of color patterns has strong resistant ability on short time heat treatment (45℃,5min) but it has weak resistant ability on long time heat treatment (45℃,10min). The tolerance of pupae to high temperature(45℃) was extreme strong. The tolerance of older larva of T.molitor to high temperature(45℃) was stronger than that of younger larva with same color pattern. There was significant difference in heat resistance between different color larvas with same-days. The tolerance of30days and60days black-color pattern larva to high temperature(45℃) was stronger than that of yellow-color pattern larva.2. The result of isozyme electrophoresis shown that the numble of enzyme band and the intensity of enzyme band of POD and CAT of larva (30d,60d,90d), pupae (2d,4d,6d) and adult (0d,15d,30d) of two kinds of color pattern of T.molitor changed by experiment high temperature (45℃) treatment. It is speculated that the thermotolerance of T.molitor may be responsible for expression of protective enzyme.3. Core fragment clone,3’RACE and5’RACE were used to obtain full squence of HSP70mRNA. T.molitor hsp70gene has2,282bp in length, and it includes one full open reading fragment which has1,935bp in length and potentially encodes645amino acid residues. Homology analysis indicated that amino acid sequence of HSP70of T.molitor had92.1%homology with it of Tribolium castaneum(red flour beetle), amino acid sequence of HSP70of T.molitor had90.4%homology with it of Anatolica polita borealis. We named hsp70gene of yellow-pattern T.molitor as Tm.YHSP70and named hsp70gene of black-pattern T.molitor as Tm.BHSP70. Tm.YHSP70and Tm.BHSP70were submitted to genebank, and acquire accession number JQ219848(Tm.YHSP70) and JQ219849(Tm.BHSP70).4. Expression of HSP70mRNA of larva (30d,60d,90d), pupae (2d,4d,6d) and adult (0d,15d,30d) on heat treatment were studied by semi quantitative RT-PCR. The result was as follows:the expression of HSP70mRNA of T.molitor was induced by heat treatment, but expression law of HSP70mRNA of different development period in stress of heat is not all same, and expression law of HSP70mRNA of different color-pattern in stress of heat is not all same to. It is speculated that there may be a relationship between the ability of heat resistance of T.molitor and the expression of HSP70.