Cloning and expression analysis of four heat shock protein genes in Ericerus pela (Homoptera: Coccidae).

Wei-Wei Liu,Xiao-Ming Chen,Yan-Hong Hu,Pu Yang,Dong-Li Xu

doi:10.1093/jisesa/ieu032

Abstract

To explore the function of small heat shock protein genes ( shsp s) and hsp70 in Ericerus pela , we cloned the full-length cDNA sequences of hsp21.5 , hsp21.7 , hsp70 , and hsc70 and the genomic sequence of hsc70 . Open reading frames of the four hsp s were 570, 564, 1,908, and 1,962 base pairs (bp), respectively, which encode proteins with calculated molecular mass of 21.5, 21.7, 69.8, and 71.6 kDa. Amino acid sequence analysis revealed the presence of the conserved Hsp motifs in all four proteins. The genomic DNA of hsc70 had four introns. ep-hsp21.5 was orthologous and ep-hsp21.7 was species specific. Expression of all four transcripts during heat or cold stress and development was examined by quantitative real-time polymerase chain reaction. All four hsp s were upregulated during heat or cold stress in female adults, indicating a correlation between the four hsp s and heat or cold-stress tolerance in female adults. ep-hsp21.7 and ep-hsp70 were upregulated during heat stress in male larvae, implying a correlation between the two hsp s and heat-stress tolerance in male larvae. The four ep-hsp s were also upregulated during the developmental process in males, and ep-hsp21.5 , ep-hsp70 , and ep-hsc70 were upregulated in females, which indicates their possible role in the developmental regulation of E. pela .

Highlights

The Chinese white wax scale insect, Ericerus pela Chavannes (Homoptera: Coccidae), is a coccid insect famous for its role in wax production
A number of shsps are reported to be involved in temperature adaptation and development
Six shsps, which are classified into three groups with diverse functions, are reported in the common cutworm, S. litura (Shen et al 2011), and three shsps are found to be responsible for cold stress and development in the leafminer, Liriomyza sativa (Huang et al 2009)

Summary

Introduction

The Chinese white wax scale insect, Ericerus pela Chavannes (Homoptera: Coccidae), is a coccid insect famous for its role in wax production. Tolerance of second-stage male larvae to high temperature stress is critically important for the wax production and male survival. In Chongqing City, where the highest temperature is 44C and the highest average monthly temperature is about 26C, E. pela can survive and carry on reproduction (Zhang and Liu 1997, Chen and Feng 2009, Chen 2011) This remarkable tolerance of E. pela to extreme hot and cold temperatures is important for wax production. Considering the critical role of Hsps in response to irreversible stress conditions in many insects, it is presumed that Hsps can be involved in the temperature adaptation of E. pela To explore this possibility, the full-length cDNA sequences of four hsps (hsp21.5, hsp21.7, hsp, and hsc70) were selected from the transcriptome of E. pela and cloned. Our results of this study will promote greater understanding of the basis for the adaptation and population variations within E. pela at a molecular level

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Results

Conclusion