Molecular and biochemical characterizationof calmodulin
fromEchinococcus granulosus
Ning Wang, Xiuqin Zhong, Xingju Song, Xiaobin Gu, Weiming Lai, Yue Xie,
Xuerong Peng and Guangyou Yang
Abstract
Background:Echinococcus granulosusis a harmful cestode parasite that causes cystic echinococcosis in humans as well as various livestock species and wild animals. Calmodulin (CaM), a Ca2+sensor protein, is widely expressed in eukaryotes and mediates a variety of cellular signaling activities.
Methods:In the present study, the cDNA encoding CaM inEchinococcus granulosus(rEgCaM) was successfully cloned and the molecular and biochemical characterizations carried out. The antigenicity and immunoreactivity of rEgCaM was detected and the preliminary enzyme-linked immunosorbent assay (ELISA)-based serodiagnostic potential of EgCaM was assessed. The locations of this protein in the adult worm and larval stage, and the mRNA expression in different states ofE. granulosusprotoscoleces (PSCs) were defined clearly. Moreover, the Ca2+-binding properties of EgCaM were measured.
Results:rEgCaM is a highly conserved calcium-binding protein, consisting of 149 amino acids. Immunoblotting analysis revealed that rEgCaM could be identified usingE. granulosusinfected sheep serum. The use of rEgCaM as an antigen was evaluated by indirect ELISA which exhibited a high sensitivity (90.3%), but low specificity (47.1%). rEgCaM was ubiquitously expressed in protoscoleces and adults ofE. granulosus, as well as in the germinal layer of the cyst wall. The mRNA expression level of rEgCaM was increased from the start of H2O2exposure and then gradually decreased because of the increased apoptosis of PSCs. In electrophoretic mobility tests and 1-anilinonaphthalene-8-sulfonic acid assays, rEgCaM showed a typical characteristic of a calcium-binding protein.
Conclusions:To our knowledge, this is the first report on CaM fromE. granulosusand rEgCaM is likely to be involved in some important biological function ofE. granulosusas a calcium-binding protein.
copyright:© The Author(s).
Parasites & Vectors(2017) 10:597. DOI: 10.1186/s13071-017-2545-2
Read FullText: www.preprints.org/manuscript/201705.0173/v1
