Characterization and expression of the Schistosoma japonicum thioredoxin peroxidase-2 gene.

Abstract

We analyzed proteins that were differentially expressed by 10-day-old schistosomula from 3 different hosts and determined that a functional thioredoxin peroxidase-2 gene has an important antioxidant role in Schistosoma japonicum , which we investigated further. A full-length cDNA encoding the S. japonicum thioredoxin peroxidase-2 (SjTPx-2) had an open reading frame of 681 bp that encoded 226 amino acids with a signal peptide of 24 amino acids. A cDNA encoding SjTPx-2 without the signal peptide sequence was isolated from 42-day-old schistosome cDNAs. Real-time quantitative RT-PCR analysis revealed that SjTPx-2 was upregulated in 7- and 13-day-old schistosomes, while the expression level in females was around 2-fold higher than that in male worms at 42 days. SjTPx was subcloned into pET28a(+) and expressed as both inclusion bodies and supernatant in Escherichia coli BL21 (DE3) cells. Western blotting showed that the recombinant SjTPx-2 (rSjTPx-2) was immunogenic. The purified recombinant protein could form disulfide-bonded dimers and it had peroxidase activity in vitro. An immunoprotection experiment in BALB/c mice showed that vaccination with recombinant SjTPx-2 could induce 31.2% and 34.0% reductions in the numbers of worms and eggs in the liver, respectively. This study suggests that SjTPx-2 may be an important antioxidative enzyme in scavenging ROS, and it may be a potential vaccine candidate or new drug target for schistosomiasis.

• Authors: Yang Hong, Yanhui Han, Zhiqiang Fu, Hongxiao Han, Chunhui Qiu, Min Zhang, Jianmei Yang, Yaojun Shi, Xiangrui Li, Jiaojiao Lin
• Journal: The Journal of parasitology (J Parasitol) Vol. 99 Issue 1 Pg. 68-76 (Feb 2013) ISSN: 1937-2345 [Electronic] United States
• PMID: 22924918 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Adjuvants, Immunologic
• Antibodies, Helminth
• Antioxidants
• Immunoglobulin G
• RNA, Messenger
• Peroxiredoxins

Topics

• Adjuvants, Immunologic (administration & dosage)
• Animals
• Antibodies, Helminth (blood)
• Antioxidants (metabolism)
• Dose-Response Relationship, Immunologic
• Female
• Gene Expression Regulation, Enzymologic
• Immunity, Cellular
• Immunoglobulin G (blood)
• Male
• Mice
• Mice, Inbred BALB C
• Peroxiredoxins (genetics, immunology, metabolism)
• Phylogeny
• RNA, Messenger (isolation & purification, metabolism)
• Rabbits
• Random Allocation
• Real-Time Polymerase Chain Reaction
• Schistosoma japonicum (classification, enzymology, genetics, immunology)
• Schistosomiasis japonica (prevention & control)
• Sex Factors
• Spleen (cytology, immunology)
• Vaccination