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Characterization of heat shock protein 70 gene from Haemonchus contortus and its expression and promoter analysis in Caenorhabditis elegans

Published online by Cambridge University Press:  29 January 2013

HONGLI ZHANG ,
QIANJIN ZHOU ,
YI YANG ,
XUEQIU CHEN ,
BAOLONG YAN  and
AIFANG DU
HONGLI ZHANG
Affiliation:
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
QIANJIN ZHOU
Affiliation:
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
YI YANG
Affiliation:
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
XUEQIU CHEN
Affiliation:
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
BAOLONG YAN
Affiliation:
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
AIFANG DU*
Affiliation:
Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
*
*Corresponding author. Tel: +86 571 88982583. Fax: +86 571 88982583. E-mail: afdu@zju.edu.cn.
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Summary

Haemonchus contortus infections in small ruminants are of major economic importance worldwide. Heat shock proteins (HSPs) are a family of molecular chaperones that play important roles in the process of invasion and survival of nematodes. Although HSP70 has been identified in several parasitic nematodes, little is known of its distribution and function in Haemonchus contortus. The aims of this study were to characterize HSP70 from Haemonchus contortus (designed as Hc-hsp70), express Hc-hsp70 and analyse the promoter activity in Caenorhabditis elegans. Bioinformatic analysis revealed that the open reading frame of the Hc-hsp70 cDNA encodes a 646-amino acid peptide, which is highly conserved in comparison to HSP70 in other nematodes. Phylogenetic analysis indicated that H. contortus is closely related to Caenorhabditis. The 5′-flanking region promoted green fluorescence protein (GFP) expression in the intestine in all larval stages and adult with 2 expression patterns in C. elegans. Expression of Hc-hsp70 mRNA transcripts in C. elegans increased following 2, 4, 6 h of heat shock and peaked at 4 h. However, its expression induced down-regulation of hsp-1 of C. elegans. These results suggest that the H. contortus hsp70 might have a similar function to that of C. elegans hsp-1.

Keywords

Haemonchus contortusHSP70promoter activityCaenorhabditis elegans
Type
Research Article
Information
Parasitology , Volume 140 , Issue 6 , May 2013 , pp. 683 - 694
Copyright
Copyright © Cambridge University Press 2013

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