The hsp27 gene of the Mediterranean fruit fly, Ceratitis capitata: structural characterization, regulation and developmental expression

Abstract

In the present study, a genomic DNA clone encoding the medfly homolog of Drosophila melanogaster hsp27 gene, named Cchsp27, was isolated. We sequenced a part of the clone containing the coding region, the 5' untranslated region and approximately 2.8 Kb of the 5' flanking region of the gene. Phylogenetic analysis of several insect small heat shock proteins, suggested that CcHsp27 is orthologous to Drosophila Hsp27 and Sarcophaga crassipalpis Hsp25. The Cchsp27 gene was mapped at the 81A division of the sixth chromosome which coincides with one of the major heat shock puffs of medfly. Structural analysis of the 5' flanking region of the Cchsp27 gene revealed the presence of five putative heat shock elements and one putative ecdysone response element. In addition to heat induction, the Cchsp27 gene was expressed at several stages of normal medfly development. In general, the developmental expression pattern of the Cchsp27 gene was similar to the respective pattern of Drosophila hsp27 gene. However, there were some important differences in certain developmental stages suggesting differential regulation of the hsp27 gene in the two dipterans species. Salivary gland culture experiments showed that the Cchsp27 gene is regulated by 20-hydroxyecdysone.

Characterization of the small heat shock protein Hsp27 gene in Chironomus riparius (Diptera) and its expression profile in response to temperature changes and xenobiotic exposures

“…Previous phylogenetic analysis that included vertebrates and plants has already suggested that different sHSPs of the same species are phylogenetically closer than homologous sHSPs between species, pointing to the possibility that sHSPs might have evolved by gene duplication after species divergence (de Jong et al 1993). However, more recent studies have indicated that several mammalian sHSPs have clearly recognizable orthologs in lower vertebrates (Franck et al 2004), while the HSP27 homologs from D. melanogaster, C. capitata, and S. crassipalpis have been separated from other dipteran sHSPs (Kokolakis et al 2008). In agreement with these data, we found that the HSP27 of C. riparius was also separated from other dipteran sHSPs, suggesting that the four proteins are orthologous and may have evolved before divergence of these species.…”

“…The second domain (aa D 37 -N 49 in ChrHSP27) shows around 50 % amino acid sequence identity among the four HSP27 homologs. This domain is very specific as it is only conserved in the HSP27 (Kokolakis et al 2008), suggesting that it may play a distinct role in this protein. The third domain, located downstream to the α-crystallin domain, contains 28 amino acids (aa K 159 -K 186 in ChrHSP27) and shows around 50 % amino acid sequence identity among the four HSP27 homologs.…”

“…Members of the α-crystallin/sHSP superfamily have recently been cloned from a few insect species: Sarcophaga crassipalpis , Venturia canescens (Reineke 2005), Bombyx mori (Sakano et al 2006), Plutella xylostella (Sonoda et al 2006), Liriomyza sp. , Locusta migratoria (Wang et al 2007), Ceratitis capitata (Kokolakis et al 2008), Mamestra brassicae (Sonoda et al 2007), Sesamia nonagrioides (Gkouvitsas et al 2008), Liriomyza sativae (Huang et al 2009), and Macrocentrus cingulum (Xu et al 2010). In the flesh fly S. crassipalpis , three sHSPs are upregulated during diapause and it has been proposed that they contribute to the survival of this insect at low temperatures (Yocum et al 1998;Li et al 2007;Rinehart et al 2007;Colinet et al 2010).…”

Molecular cloning and characterization of Hsp27.6: the first reported small heat shock protein from Apis cerana cerana

“…They share significant sequence similarity and are coordinately expressed following stress, but they have distinct developmental expression patterns and intracellular localizations (Michaud et al 2002). Recently, a few members of the α-crystallin/sHSP family have been cloned from other insect species, including Plutella xylostella (Sonoda et al 2006), Mamestra brassicae (Sonoda et al 2007), Ceratitis capitata (Kokolakis et al 2008), Sesamia nonagrioides (Gkouvitsas et al 2008), Liriomyza sativa (Huang et al 2009), and Macrocentrus cingulum (Xu et al 2010).…”

“…An online protein 3D structure prediction tool (http://swissmodel.expasy.org/) was also used in the structural analysis. Multiple sequence alignments were performed using the Clustal X program with its default parameters (Kokolakis et al 2008). Phylogenetic and molecular evolutionary analyses were performed using the neighbor-joining method with the Molecular Evolutionary Genetics Analysis (MEGA version 4.1) software.…”