Molecular characterization and immunolocalization of a protein disulfide isomerase from Angiostrongylus cantonensis

Abstract

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.

Meloidogyne graminicola protein disulfide isomerase may be a nematode effector and is involved in protection against oxidative damage

“…The reduction of cCMP by active RNase into CMP was monitored by the absorbance at 296 nm for 60 min in a Microplate Reader (Thermo, Varioskan Flash). For the PDI reductive assay, the MgPDI enzyme activity to reduce insulin was determined by a modified method 41,42 . Reaction mixtures (200 μl) included 100 mM Tris-Cl (pH 6.8), 2 mM ethylenediaminetetraacetic acid (EDTA), 0.13 mM insulin from bovine pancreas (Sigma), 0.33 mM dithiothreitol (DTT) and increasing concentrations (ranging from 2.5 to 10 μM) of purified MgPDI protein.…”

Molecular cloning and characterization of protein disulfide isomerase of Brugia malayi, a human lymphatic filarial parasite

“…Proper folding of proteins is necessary for parasite reproduction, development and play a pivotal role in host parasite interactions. Recently it was shown that PDI is vigorously expressed in the uterus wall and oocyte of female adult A. cantonensis worms (Liu et al, 2012[ 28 ]). The formation and maturation of proteins occur throughout the whole life and vitellogenins are prevalent proteins in adult female nematodes that are synthesized in a large amount to support developing oocytes (Nisbet et al, 2010[ 37 ]).…”

Identification and characterisation of microRNAs in young adults of Angiostrongylus cantonensis via a deep-sequencing approach

“…The transcripts found in pepsin-activated infective larvae (3rd-stage) encode proteins that participate in a wide range of biological processes (Chang et al 2011). Although cloning of galectin (Hao et al 2007), cystatin (Liu et al 2010), Ac16 (Li et al 2011), cathepsin B (Han et al 2011), a cathepsin B-like cysteine proteinase (Cheng et al 2012) and a protein disulphide isomerase (Liu et al 2012) has been accomplished in A . cantonensis , the characterisation of these proteins is far from complete.…”