Five small heat shock protein genes from Chilo suppressalis: characteristics of gene, genomic organization, structural analysis, and transcription profiles

Abstract

Small heat shock proteins (sHSPs) are the most diverse but also the most poorly known family of molecular chaperones, and they play essential roles in various biological processes. The striped stem borer, Chilo suppressalis (Insecta: Lepidoptera: Pyralidae), is one of the most serious pests of rice, causing extensive damage and yield loss. In this study, we isolated and characterized five members of the sHSPs family-Cshsp19.8, Cshsp21.4, Cshsp21.5, Cshsp21.7a, and Cshsp21.7b-from C. suppressalis. The cDNAs of these genes encoded proteins of 177, 187, 191, 191, and 191 amino acids with isoelectric points of 7.0, 5.6, 6.1, 6.3, and 6.3, respectively. While Cshsp19.8, Cshsp21.5, and Cshsp21.7b had no introns, Cshsp21.4 and Cshsp21.7a contained one and two introns, respectively. Structural analysis indicated that all five Cshsps possessed conserved arginine and a V/IXI/V motif, which is related to hydrophobic characteristics of sHSPs. The five heat shock proteins can be classified into two main groups: an orthologous type (Cshsp21.4 and Cshsp21.7a) and a species-specific type (Cshsp19.8, Cshsp21.5, and Cshsp21.7b). Real-time quantitative PCR analyses revealed that Cshsp19.8, Cshsp21.5, Cshsp21.7a, and Cshsp21.7b all exhibited their highest expression levels within Malpighian tubules or the hindgut, while such levels were found in the head for Cshsp21.4. The expression of Csshsps at different developmental stages revealed that the mRNA levels of Cshsp19.8, Cshsp21.4, Cshsp21.5, and Cshsp21.7b peaked in adults, whereas the highest level of Cshsp21.7a was observed in first instar larvae. Cshsp19.8 and Cshsp21.7b were both upregulated dramatically by heat and cold, and Cshsp21.5 could be induced by cold stress. Neither Cshsp21.4 nor Cshsp21.7a responded to heat or cold. These results demonstrated that different Csshsps play distinctive roles in the regulation of the physiological activities in C. suppressalis.

Characterization of six small HSP genes from Chironomus riparius (Diptera, Chironomidae): Differential expression under conditions of normal growth and heat-induced stress

“…Phylogenetic analysis of C. riparius sHSPs suggests the existence of three groups: one formed by CrHSP34 and CrHSP23, a second one formed by CrHSP21, and a third one comprised by the others. These results agree with previous data available for other species (Shen et al, 2011;Lu et al, 2014) which were used in the phylogenetic analysis (Supplementary material), suggesting a gradual emergence of new sHSP genes. However, comparison of individual evolutionary trees suggests that evolution of this family of genes may be more complex than previously thought and may involve several mechanisms depending on the species.…”

“…The genes have been named according to the molecular weight of the predicted protein as CrHsp17, CrHsp21, CrHsp22, CrHsp23, CrHsp24, and CrHsp34. Previous studies in insects have identified several members of this family in different species (Li et al, 2009;Shen et al, 2011;Lu et al, 2014) including the sibling species Chironomus tentans (Vincent and Tanguay, 1979;Tanguay and Vincent, 1981) but there were differences in the number of representatives. In this study, we describe seven sHSPs in C. riparius, which is the same number proposed for A. gambiae and four less than for D. melanogaster (Li et al, 2009).…”

Small heat shock proteins, phylogeny in filamentous fungi and expression analyses in Aspergillus nidulans

“…Expression of A. nidulansshsp genes A) in different developmental stages, B) responding to thermal and cold stresses, C) responding to osmotic pressure and D) responding to oxidative stress. 2014; Chen and Zhang, 2014), and in Chilo suppressalis, Cshsp19.8 and Cshsp21.7b were both upregulated dramatically by heat and cold (Lu et al, 2014). In our study, all A. nidulans shsp genes but AN10507 were strongly induced when subjected to heat and cold pressure.…”

Characterization and functional analysis of hsp21.8b: An orthologous small heat shock protein gene in Tribolium castaneum

“…This phenomenon is due to that the female insects enter the adult stage in August (hot weather), whereas the male larvae continuously keep in the second‐instar stage. In kinds of moths ( Plutella xylostella , C. suppressalis and S. inferens ) , the lowest expression of hsp21.4 was observed in embryonic or larval stages, and the highest expression was found in adult stage (Chen & Zhang, ; Lu, Hua, Cui, & Du, ; Sun et al., ). Moreover, hsp21.4 was most strongly expressed in the head, gut or malpighian tubule of these moths, which all belonged to important detoxification tissues mainly because the sHSP could protect the insects from external injury in the adult stage (Lu et al., ; Sun et al., ).…”

“…Then, the orthologous shsps , similar with the species‐specific shsps , could be classified into three types depending on the different reactions to the temperature stimuli. The first type, like Cshsp21.4 and Slhsp21.4 , was insensitive to heat or cold stress (Lu et al., ; Shen et al., ). And the second type can be upregulated under temperature stress conditions.…”