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Updated: Jun 23, 2026
Purification of Biotinylated Cell Surface Proteins from Rhipicephalus microplus Epithelial Gut Cells
Published on: July 23, 2017
Antimicrobial activity in the tick Rhipicephalus (Boophilus) microplus eggs: Cellular localization and temporal
E Esteves1, A C Fogaça, R Maldonado
1Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil.
Abstract:
Arthropods display different mechanisms to protect themselves against infections, among which antimicrobial peptides (AMPs) play an important role, acting directly against invader pathogens. We have detected several factors with inhibitory activity against Candida albicans and Micrococcus luteus on the surface and in homogenate of eggs of the tick Rhipicephalus (Boophilus) microplus. One of the anti-M. luteus factors of the egg homogenate was isolated to homogeneity. Analysis by electrospray mass spectrometry (ESI-MS) revealed that it corresponds to microplusin, an AMP previously isolated from the cell-free hemolymph of R. (B.) microplus. Reverse transcription (RT) quantitative polymerase chain reactions (qPCR) showed that the levels of microplusin mRNA gradually increase along ovary development, reaching an impressive highest value three days after the adult females have dropped from the calf and start oviposition. Interestingly, the level of microplusin mRNA is very low in recently laid eggs. An enhance of microplusin gene expression in eggs is observed only nine days after the onset of oviposition, achieving the highest level just before the larva hatching, when the level of expression decreases once again. Fluorescence microscopy analysis using an anti-microplusin serum revealed that microplusin is present among yolk granules of oocytes as well as in the connecting tube of ovaries. These results, together to our previous data, suggest that microplusin may be involved not only in protection of adult female hemocele, but also in protection of the female reproductive tract and embryos, what points this AMP as a considerable target for development of new methods to control R. (B.) microplus as well as the vector-borne pathogens.
Insights
Antimicrobial peptides (AMPs) like microplusin protect ticks from pathogens. This study found microplusin in Rhipicephalus (Boophilus) microplus eggs, suggesting its role in protecting tick embryos and controlling tick populations.
Area of Science:
- Zoology
- Immunology
- Molecular Biology
Background:
- Arthropods utilize antimicrobial peptides (AMPs) for pathogen defense.
- The tick Rhipicephalus (Boophilus) microplus is a significant vector of diseases.
Purpose of the Study:
- To investigate the presence and role of antimicrobial factors in Rhipicephalus (Boophilus) microplus eggs.
- To characterize the expression patterns of microplusin during tick reproduction and development.
Main Methods:
- Isolation and identification of antimicrobial factors from tick egg homogenates using electrospray mass spectrometry (ESI-MS).
- Quantitative polymerase chain reaction (qPCR) to analyze microplusin mRNA expression levels.
- Fluorescence microscopy to visualize microplusin localization within tick reproductive tissues and eggs.
Main Results:
- An antimicrobial peptide, microplusin, was identified in Rhipicephalus (Boophilus) microplus eggs.
- Microplusin mRNA levels increase during ovary development and are high in mature eggs before hatching.
- Microplusin is localized within oocytes and ovarian tissues, indicating its presence in the female reproductive system.
Conclusions:
- Microplusin plays a crucial role in protecting the female reproductive tract and developing embryos of Rhipicephalus (Boophilus) microplus.
- Microplusin represents a potential target for developing novel strategies to control Rhipicephalus (Boophilus) microplus and associated vector-borne diseases.
