CONCLUSION

In this experiment, by confocal microscopic findings, the Nfa1 protein located on cell surface of N. fowleri trophozoites, especially pseudopodia. The Nfa1 protein in N.

fowleri trophozoites co-cultured with CHO cells located on pseudopodia that contacted with target cells and in a food-cup that formed as a phagocytic structure.

Finally, in this study it was elucidated that the Nfa1 protein is involved in the food-cup formation which play an important role of phagocytic activity as a cell-contact mechanism in pathogenic N. fowleri.

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자유아메바의 병원성에 대해 많은 연구에도 불구하고, 이 생물체의 탐식기능(phagocytosis)과 관련된 단백질은 아직 별로 알려져 있지 않다. 본 연구에서는, Confocal microscope를 이용한 immunofluorescence 분석을 통하여 표적세포와 혼합배양된 파울러 자유아메바의 세포-접촉 기전에서 Nfa1 단백질의 위치와 역할을 관찰하였다. Confocal microscope 관찰 결과, Nfa1 단백질은 파울러 자유아메바의 세포 표면 특히, 위족에 위치하고 있었다. 그리고 표적세포와 혼합배양시 파울러 자유아메바에서의 Nfa1 단백질은 표적세포와 접촉하고 있는 위족에 밀집되어 있었고 특히, 식세포 작용을 하는 구조체로 형성된 food-cup에서 뚜렷한 발현양상을 보여주었다. 따라서 병원성의 파울러 자유아메바의 Nfa1 단백질은 아메바의 위족활동에 중요한 역할을 하며, 특히, 표적세포와의 접촉시, 아메바의 식세포 작용을 하는 food-cup의 형성과 활동에 매우 중요한 역할을 하고 있다는 것을 알 수 있었다.

핵심되는 말 : 파울러 자유아메바, 유전자 클로닝, 재조합 단백질, Nfa1 단백질, Confocal microscope