Molecular characterization and immunolocalization of a protein disulfide isomerase from Angiostrongylus cantonensis.
Protein disulfide isomerases (PDIs), belonging to the thioredoxin superfamily, are oxidoreductases that catalyze the formation, reduction, and isomerization of disulfide bonds among cysteine residues of proteins. In this study, we report the cloning and characterization of a cDNA encoding a protein disulfide isomerase (AcPDI) from a cDNA library of fourth-stage larvae of Angiostrongylus cantonensis. The deduced amino acid sequence contains two thioredoxin domains and exhibits high identity to the homologues from other species. Quantitative real-time PCR (qRT-PCR) was performed at the third-stage larvae, fourth-stage larvae, and adult stage of A. cantonensis, and the results revealed that the AcPDI mRNA, while expressed at all three stages, is expressed at a significantly higher level in female adult worms. Results of immunohistochemical studies indicated that the AcPDI expression was specifically localized in the tegument and uterus wall of female adult worms. Biochemical analysis showed that recombinant AcPDI was biologically active in vitro and exhibited the typical biochemical functions of PDIs: oxidase/isomerase and reductase activities. Collectively, these results implied that AcPDI may be a female-enriched protein and associated with the reproductive development of A. cantonensis. In addition, considering its biochemical properties, AcPDI may be involved in the formation of the cuticle of A. cantonensis.
Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2 Road, Guangzhou, Guangdong, 510089, People's Republic of China.
Qian
Q
Liu
Xiao
X
Yang
Meichun
M
Zhang
Lin
L
Wang
Jing
J
Liu
Jing
J
Chen
Ai
A
He
Zhuoya
Z
Li
Zhongdao
Z
Wu
Ximei
X
Zhan
D000595:Amino Acid Sequence; D017185:Angiostrongylus cantonensis / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics*; D000825:Animal Structures / Q000737:chemistry / Q000201:enzymology; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D007150:Immunohistochemistry; D007814:Larva / Q000737:chemistry / Q000201:enzymology / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D019704:Protein Disulfide-Isomerases / Q000032:analysis* / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D019704:Protein Disulfide-Isomerases