Dataset Information

Molecular and functional characterization of a putative PA28? proteasome activator orthologue in Schistosoma mansoni.

ABSTRACT: PA28? is a proteasome activator involved in the regulation of the cellular proliferation, differentiation and growth. In the present study, we identified and characterized a cDNA from Schistosoma mansoni exhibiting significant homology to PA28? of diverse taxa ranging from mammals (including humans) to simple invertebrates. Designated SmPA28?, this transcript has a 753bp predicted ORF encoding a protein of 250 amino acid residues. Alignment of SmPA28? with multiple PA28? orthologues revealed an average similarity of ~40% among the investigated organisms, and 90% similarity with PA28? from Schistosoma japonicum. In addition, phylogenetic analysis demonstrated a close linkage between SmPA28? to its sister group that contains well-characterized PA28? sequences from Drosophila spp., as well as sharing the same branch with PA28? from S. japonicum. Gene expression profiling of SmPA28? using real-time quantitative PCR revealed elevated steady-state transcript levels in the eggs, miracidia and paired adult worms compared to other stages. In parallel with gene expression profiles, an affinity-purified anti-SmPA28? antibody produced against recombinant protein exhibited strongest reactivity in Western blot analyses to endogenous SmPA28? from miracidia, sporocysts and paired adult worms. Given its known regulatory function in other organisms, we hypothesized that the high level of SmPA28? transcript and protein in these stages may be correlated with an important role of the PA28? in the cellular growth and/or development of this parasite. To address this hypothesis, miracidia were transformed in vitro to sporocysts in the presence of SmPA28? double-stranded RNAs (dsRNAs) and cultivated for 4 days, after which time steady-state transcript and protein levels, and phenotypic changes were evaluated. SmPA28? dsRNA treatment resulted in gene and protein knockdown of ~60% and ~80%, respectively, which were correlated with a significant decrease in larval length compared to its controls. These findings are consistent with a putative role of SmPA28? in larval growth/development of the S. mansoni.

SUBMITTER: Soares CS

PROVIDER: S-EPMC3712533 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Molecular and functional characterization of a putative PA28γ proteasome activator orthologue in Schistosoma mansoni.

Soares Cláudia Sossai CS Morais Enyara Rezende ER Magalhães Lizandra G LG Machado Carla Botelho CB Moreira Érika Bueno de Carvalho ÉB Teixeira Felipe Roberti FR Rodrigues Vanderlei V Yoshino Timothy P TP

Molecular and biochemical parasitology 20130420 1-2

PA28γ is a proteasome activator involved in the regulation of the cellular proliferation, differentiation and growth. In the present study, we identified and characterized a cDNA from Schistosoma mansoni exhibiting significant homology to PA28γ of diverse taxa ranging from mammals (including humans) to simple invertebrates. Designated SmPA28γ, this transcript has a 753bp predicted ORF encoding a protein of 250 amino acid residues. Alignment of SmPA28γ with multiple PA28γ orthologues revealed an ...[more]

PMID: 23611749

Similar Datasets

Project description:Proteasome is a proteolytic complex responsible for intracellular protein turnover in eukaryotes, archaea and in some actinobacteria species. Previous work has demonstrated that in Schistosoma mansoni parasites, the proteasome inhibitor MG-132 affects parasite development. However, the molecular targets affected by MG-132 in S. mansoni are not entirely known. Here, we used expression microarrays to measure the genome-wide changes in gene expression of S. mansoni adult worms exposed in vitro to MG-132, followed by in silico functional analyses of the affected genes using Ingenuity Pathway Analysis (IPA). Scanning electron microscopy was used to document changes in the parasites' tegument. We identified 1,919 genes with a statistically significant (q-value ? 0.025) differential expression in parasites treated for 24 h with MG-132, when compared with control. Of these, a total of 1,130 genes were up-regulated and 790 genes were down-regulated. A functional gene interaction network comprised of MG-132 and its target genes, known from the literature to be affected by the compound in humans, was identified here as affected by MG-132. While MG-132 activated the expression of the 26S proteasome genes, it also decreased the expression of 19S chaperones assembly, 20S proteasome maturation, ubiquitin-like NEDD8 and its partner cullin-3 ubiquitin ligase genes. Interestingly, genes that encode proteins related to potassium ion binding, integral membrane component, ATPase and potassium channel activities were significantly down-regulated, whereas genes encoding proteins related to actin binding and microtubule motor activity were significantly up-regulated. MG-132 caused important changes in the worm tegument; peeling, outbreaks and swelling in the tegument tubercles could be observed, which is consistent with interference on the ionic homeostasis in S. mansoni. Finally, we showed the down-regulation of Bax pro-apoptotic gene, as well as up-regulation of two apoptosis inhibitor genes, IAP1 and BRE1, and in contrast, down-regulation of Apaf-1 apoptotic activator, thus suggesting that apoptosis is deregulated in S. mansoni exposed to MG-132. A considerable insight has been gained concerning the potential of MG-132 as a gene expression modulator, and overall the data suggest that the proteasome might be an important molecular target for the design of new drugs against schistosomiasis.

Dataset Information

Molecular and functional characterization of a putative PA28? proteasome activator orthologue in Schistosoma mansoni.

Publications

Molecular and functional characterization of a putative PA28γ proteasome activator orthologue in Schistosoma mansoni.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets