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Flow Cytometric Characterization of Murine B Cell Development
Published on: January 22, 2021
Characterization of MEDLE-1, a protein in early development of Cryptosporidium parvum
Jilan Fei1, Haizhen Wu2, Jiayuan Su1
1State Key Laboratory of Bioreactor Engineering, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Background:
Cryptosporidium spp. are important diarrhea-causing pathogens in humans and animals. Comparative genomic analysis indicated that Cryptosporidium-specific MEDLE family proteins may contribute to host adaptation of Cryptosporidium spp., and a recent study of one member of this family, CpMEDLE-2 encoded by cgd5_4590, has provided evidence supporting this hypothesis. In this study, another member of the protein family, CpMEDLE-1 of Cryptosporidium parvum encoded by cgd5_4580, which is distinct from CpMEDLE-2 and has no signature motif MEDLE, was cloned, expressed and characterized to understand its function.
Methods:
CpMEDLE-1 was expressed in Escherichia coli and polyclonal antibodies against the recombinant CpMEDLE-1 protein were prepared in rabbits. Quantitative PCR was used to analyze the expression profile of cgd5_4580 in C. parvum culture. Immunofluorescence staining was used to locate CpMEDLE-1 expression in life-cycle stages, and in vitro neutralization assay with antibodies was adopted to assess the role of the protein in C. parvum invasion.
Results:
The results indicated that cgd5_4580 had a peak expression at 2 h of C. parvum culture. CpMEDLE-1 was located in the mid-anterior region of sporozoites, probably within the dense granules. The neutralization efficiency of anti-CpMEDLE-1 antibodies was approximately 40%.
Conclusions:
The differences in protein and gene expression profiles between CpMEDLE-1 and CpMEDLE-2 suggest that MEDLE proteins have different subcellular locations, are developmentally regulated, could be potentially involved in the transcriptional regulation of the expression of parasite or host proteins and may exert their functions in different stages of the invasion and development process.
Insights
Researchers studied Cryptosporidium parvum
Area of Science:
- Parasitology
- Molecular Biology
- Host-Pathogen Interactions
Background:
- Cryptosporidium spp. are significant causes of diarrhea in humans and animals.
- MEDLE family proteins are implicated in Cryptosporidium host adaptation.
- CpMEDLE-2, a MEDLE protein, has shown evidence supporting this hypothesis.
Purpose of the Study:
- To characterize CpMEDLE-1, a distinct member of the MEDLE protein family from Cryptosporidium parvum.
- To understand the function of CpMEDLE-1 in the context of parasite-host interactions.
Main Methods:
- Cloning, expression, and purification of CpMEDLE-1.
- Generation of polyclonal antibodies against CpMEDLE-1.
- Quantitative PCR for gene expression analysis.
- Immunofluorescence microscopy for protein localization.
- In vitro neutralization assays to assess invasion inhibition.
Main Results:
- CpMEDLE-1 gene expression peaked at 2 hours in C. parvum culture.
- CpMEDLE-1 was localized to the mid-anterior region of sporozoites, likely in dense granules.
- Anti-CpMEDLE-1 antibodies showed approximately 40% neutralization efficiency against C. parvum invasion.
Conclusions:
- CpMEDLE-1 and CpMEDLE-2 exhibit distinct expression patterns and subcellular localizations.
- MEDLE proteins may be developmentally regulated and involved in transcriptional regulation.
- These proteins likely play roles in different stages of parasite invasion and development.
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