Biomphalaria glabrata peroxiredoxin: Effect of Schistosoma mansoni infection on differential gene regulation

Abstract

To identify gene(s) that may be associated with resistance/susceptibility in the intermediate snail host Biomphalaria glabrata to Schistosoma mansoni infection, a snail albumen gland cDNA library was differentially screened and a partial cDNA encoding an antioxidant enzyme thioredoxin peroxidase (Tpx), or peroxiredoxin (Prx), was identified. The 753 bp full-length, single-copy, constitutively expressed gene now referred to as BgPrx4 was later isolated. BgPrx4 is a 2-Cys peroxiredoxin containing the conserved peroxidatic cysteine (C P ) in the N-terminus and the resolving cysteine (C R ) in the C-terminus. Sequence analysis of BgPrx4 from both resistant and susceptible snails revealed the presence of several (at least 7) Single Nucleotide Polymorphisms (SNPs). Phylogenetic analysis indicated BgPrx4 to resemble a homolog of human peroxiredoxin, PRDX4. Northern analysis of hepatopancreas RNA from both resistant and susceptible snails showed that upon parasite exposure there were qualitative changes in gene expression. Quantitative real-time RT-PCR analysis showed differences in the levels of BgPrx4 transcript induction following infection, with the transcript up-regulated in resistant snails during the early phase (5 h) of infection compared to susceptible snails in which it was down-regulated within the early time period. While there was an increase in transcription in susceptible snails later (48 h) post-infection, this never reached the levels detected in resistant snails. A similar trend -higher, earlier up-regulation in the resistant snails but lower, slower protein expression in susceptible snails -was observed by Western blot analysis. Enzymatic analysis of the purified, recombinant BgPrx4 revealed the snail sequence to function as Prx but with an unusual ability to use both thioredoxin and glutathione as substrates.

Resistance of Biomphalaria glabrata 13-16-R1 snails to Schistosoma mansoni PR1 is a function of haemocyte abundance and constitutive levels of specific transcripts in haemocytes

“…The findings for prx1 and infPhox echoe a similar change reported for peroxiredoxin 4 ( prx4 ) by Knight et al (2009). Peroxiredoxins require conserved cysteines to scavenge (detoxify) hydrogen peroxide (H 2 O 2 ).…”

Differential Protein Expression in the Hemolymph of Bithynia siamensis goniomphalos Infected with Opisthorchis viverrini

“…In B . glabrata snails, it has been previously shown that the differential capability of host defense responses in susceptible and resistant snails could have different effects on enzyme activity due to the differences in the levels of these enzymes in each strain [31, 79, 80]. Serpin is a serine protease inhibitor that was only found expressed in plasma with an up-regulated expression profile at 24 and 48 hpi.…”

Schistosoma mansoni infection of juvenile Biomphalaria glabrata induces a differential stress response between resistant and susceptible snails

“…The 25 μl final reaction volume contained; 200 nM of each gene specific primers for nimbus RT (Raghavan, et al, 2003) and Hsp 70 or 50 nM of the housekeeping gene, myoglobin primers (Raghavan, et al, 2003). Reactions were performed in a one-step format with the first stand cDNA synthesis and Real time PCR amplification done in a single tube in triplicate as described previously (Knight, et al, 2009). Each reaction contained a no template negative control to rule out non-specific amplification from contamination in the buffers and data was normalized using myoglobin as the reference housekeeping gene.…”