ABSTRACT
For further research of the apoptosis mechanism of Schistosoma japonicum (S. japonicum). The cDNA encoding Sjcaspase3 of Schistosoma japonicum was amplified by polymerase chain reaction (PCR) technique, which contained 900 nucleotides and encoded 299 amino acids. The theory molecular weight and isoelectric point (PI) of the deduced protein is 33.5 kDa and 6.39, respectively. Real-time PCR was used to analyze the transcription profiles of Sjcaspase3 at different development stages of S. japonicum. The results showed that this gene was expressed in all stages of S. japonicum with the highest expression in 21d worms, and the level of gene transcription in 42 d female worms was higher than that of male worms. The recombinant plasmid pXJ40-FLAG-Sjcaspase3 was constructed and transfection into Hela cells successfully. Real-time PCR and Western blotting analysis showed Sjcaspase3 was successfully expressed in Hela cells. Enzyme activity analysis revealed that recombinant Sjcaspase3 possessed the activity to cut substrate DEVD. Flow cytometry proved that Sjcaspase3 could induce early apoptosis of Hela cells. The results provide the basis for proceeding further study on the biological function of Sjcaspase3 and better understand the apoptosis mechanism of S. japonicum.
Subject(s)
Animals , Female , Humans , Male , Apoptosis , Blotting, Western , Caspase 3 , Genetics , Metabolism , Cloning, Molecular , DNA, Complementary , HeLa Cells , Helminth Proteins , Genetics , Metabolism , Real-Time Polymerase Chain Reaction , Recombinant Proteins , Schistosoma japonicumABSTRACT
Radiation sensitive protein 23 (RAD23) is a nucleotide excision repair (NER) protein that plays an important role in Ubiquitin-proteasome pathway (UPP). Schistosoma japonicum radiation sensitive protein23 (SjRAD23) cDNA sequences were amplified by PCR and cloned into pET28a (+) vector to construct recombinant expression plasmid pET28a(+)-SjRAD23. The recombinant protein was expressed as both inclusion bodies and the supernatant in Escherichia coli BL21 (DE3) cell. Immunofluorescence observation shows that SjRAD23 was mainly distributed on the tegument surface of the worms. ELISA assay reveals that specific IgG, IgG1 and IgG2a antibodies could be detected in the sera of rSjRAD23 immunized mice. Western blotting analysis shows that the recombinant SjRAD23 could be recognized by serum specific to soluble adult worm antigen of S. japonicum. BALB/c mice vaccinated with rSjRAD23 combined with 206 adjuvant revealed 35.94% worm reduction and 40.59% liver egg reduction when compared with that of the adjuvant control
Subject(s)
Animals , Mice , Antibodies, Helminth , Blood , Blotting, Western , Cloning, Molecular , DNA Repair Enzymes , Genetics , Metabolism , DNA, Complementary , Enzyme-Linked Immunosorbent Assay , Escherichia coli , Genetic Vectors , Helminth Proteins , Genetics , Allergy and Immunology , Immunoglobulin G , Blood , Mice, Inbred BALB C , Recombinant Proteins , Genetics , Allergy and Immunology , Schistosoma japonicum , Genetics , Metabolism , Schistosomiasis japonica , Vaccines , Allergy and ImmunologyABSTRACT
Objective To clone cDNA encoding troponin T of Schistosoma japonicum(SjTnT),and evaluate the protective efficacy induced by recombinant SjTnT in BALB/c mice against S. japonicum challenge infection. Methods The SjTnT gene was amplified from 28-day-schistosome cDNAs by PCR and then subcloned into pET28a(+). The recombinant SjTnT protein (rSjTnT)was expressed in Escherichia coli BL21(DE3)cells. The serum specific to rSjTnT was prepared by immunized BALB/c mice with the recombinant antigen,and the immunogenicity of rSjTnT was detected by Western blotting and ELISA. The immuno-protective efficacy induced by rSjTnT in BALB/c mice was evaluated according to the reduction in worm and egg counts. Results The cDNA encoding SjTnT was successfully cloned and expressed in E. coli. Western blotting showed that rSjTnT had a good immunogenicity. The high level of specific IgG antibodies was detected,and 33.89% worm reduction and 43.94% liver egg reduction were obtained in mice vaccinated with rSjTnT combined with Seppic 206 adjuvant compared with those in the adjuvant control group. Conclusions rSjTnT could induce partial immuno-protection against S. japonicum infec-tion in BALB/c mice. This study provided a basic for understanding the biological function of SjTnT.
ABSTRACT
The 26S proteasome is a proteolytic complex responsible for the degradation of the vast majority of eukaryotic proteins. Regulated proteolysis by the proteasome is thought to influence cell cycle progression, transcriptional control, and other critical cellular processes. A novel Schistosoma japonicum gene (GenBank Accession No. AY813725) proteasome alpha2 subunit (SjPSMA2) was cloned. Sequence analysis revealed that the ORF of SjPSMA2 gene contains 708 nucleotides encoding 235 amino acids, and the molecular weight was estimated to be 25.84 kDa. Real-time PCR analysis showed that this gene expressed in 7 d, 13 d, 18 d, 23 d, 32 d and 42 d schistosoma. The mRNA level of SjPSMA2 was lower in 7 d and 23 d schistosomulum than that in other stages. The SjPSMA2 cDNA fragment was subcloned into an expression vector pET28a(+) and transformed into E. coli BL21 (DE3) cells. After induction with IPTCQ the 30 kDa fusion protein was produced as included bodies. Western-blotting revealed that the fusion protein could be recognized by the rabbit serum anti-Schistosoma japonicum adult worm antigen preparation, and the protein in native could be detected. After immunization of BALB/c mice with the fusion protein, the reduction rates of worm counts and liver egg counts were 12.33% and 35.23%. ELISA results revealed that the vaccinated group showed a significant increase in the level of IgG antibody. This study provided an important basis for investigating the regulation mechanism of the proteasome during the development of Schistosoma japonicum.
Subject(s)
Animals , Male , Mice , Rabbits , Antibodies, Helminth , Blood , Base Sequence , Cloning, Molecular , Escherichia coli , Genetics , Metabolism , Genes, Helminth , Helminth Proteins , Genetics , Metabolism , Immunization , Liver , Parasitology , Mice, Inbred BALB C , Molecular Sequence Data , Parasite Egg Count , Proteasome Endopeptidase Complex , Genetics , Allergy and Immunology , Recombinant Proteins , Genetics , Allergy and Immunology , Schistosoma japonicum , Genetics , Metabolism , Vaccines, Synthetic , Allergy and ImmunologyABSTRACT
The present study was intend to clone and express the cDNA encoding Cyclophilin B (CyPB) of Schistosoma japonicum, its preliminary biological function and further immunoprotective effect against schistosome infection in mice. RT-PCR technique was applied to amplify a full-length cDNA encoding protein Cyclophilin B (Sj CyPB) from schistosomula cDNA. The expression profiles of Sj CyPB were determined by Real-time PCR using the template cDNAs isolated from 7, 13, 18, 23, 32 and 42 days parasites. The cDNA containing the Open Reading Frame of CyPB was then subcloned into a pGEX-6P-1 vector and transformed into competent Escherichia coli BL21 for expressing. The recombinant protein was renaturated, purified and its antigenicity were detected by Western blotting, and the immunoprotective effect induced by recombinant Sj CyPB was evaluated in Balb/C mice. The cDNA containing the ORF of Sj CyPB was cloned with the length of 672 base pairs, encoding 223 amino acids. Real-time PCR analysis revealed that the gene had the highest expression in 18-day schistosomula, suggesting that Sj CyPB was schistosomula differentially expressed gene. The recombinant protein showed a good antigenicity detected by Western blotting. Animal experiment indicated that the vaccination of recombinant CyPB protein in mice led to 31.5% worm and 41.01% liver egg burden reduction, respectively, compared with those of the control. A full-length cDNA differentially expressed in schistosomula was obtained. The recombinant Sj CyPB protein could induce partial protection against schistosome infection.