SUBCELLULAR LOCALIZATION AND ADHESION CHARACTERISTICS OF FIBRONECTIN TYPE Ⅲ DOMAIN-CONTAINING PROTEIN IN CRYPTOSPORIDIUM PARVUM
10.3969/j.issn.1005-0507.2024.03.001
- VernacularTitle:微小隐孢子虫含有纤维连接蛋白Ⅲ型结构域蛋白的亚细胞定位及其细胞黏附特性研究
- Author:
Zi-Qiang WANG
1
;
Dong-Qiang WANG
;
Ting-Ting WU
;
Guan ZHU
;
Ji-Gang YIN
Author Information
1. 人畜共患传染病重症诊治全国重点实验室,吉林大学人兽共患病研究所/动物医学学院,长春 130062
- Keywords:
Cryptosporidium parvum;
Fibronectin type Ⅲ domains;
Heparin;
Adhesion
- From:
Acta Parasitologica et Medica Entomologica Sinica
2024;31(3):129-136
- CountryChina
- Language:Chinese
-
Abstract:
Objective This study was performed to investigate the subcellular localization and adhesion properties of the Cryptosporidium parvum fibronectin type Ⅲ domain-containing protein(CpFN3).CpFN3 is a 2 430-aa single-pass type Ⅰ membrane protein encoded by the cgd4_640 gene.Methods A CpFN3-epitope short peptide was designed to immunize two specific pathogen-free rabbits,from which polyclonal antibodies were affinity-purified.As expected,this antibody detected a 280 kDa band on Western blot analysis of a crude sporozoite extract.In an immunofluorescence assay,the antibody labeled the surface of C.parvum sporozoites and trophozoites mainly in granular form.The antibody labeled all lifecycle stages,from sporozoites to intracellular asexual and sexual stages.A protein fragment spanning the FN3 domain was expressed as a His-tagged recombinant protein(His-CpFN3)in bacteria and purified to determine binding kinetics by ELISA.Results In congruence with the presence of the FN3 domain,His-CpFN3 displayed high binding affinity to fixed HCT-8 with an apparent Kd of 0.23 μmol/L and to heparin with a Kd of 1.21 μmol/L.Conclusions Binding kinetics for both targets showed dose-dependence and saturability,indicating that binding is specific in both cases.The data suggest that CpFN3 may play a role in parasite-host adhesion.