Abstract
Giardia intestinalis undergo biochemical and morphological changes to survive under extreme environmental conditions. One of these changes is encystation. The trophozoites colonizing the upper part of the small intestine differentiate into a cyst, the infective form of the parasite. In in vitro cultures, the formation of cysts is induced by the depletion of cholesterol. It was reported that Giardia cannot synthesize cholesterol de novo. However, through bioinformatic studies, we found the genes that codify for the enzymes in the cholesterol biosynthesis pathway. We were able to verify the existence and define the transcription of four genes in the trophozoite and in parasites subjected to the encystation and excystation processes.
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Acknowledgements
This project was supported by grants of the Instituto para el Desarrollo de la Ciencia ‘Francisco José de Caldas’ (COLCIENCIAS)–Project 1101.0514649 and the Universidad Nacional de Colombia (División de Investigaciones Bogotá, DIB). The experiments described in this paper comply with the current laws of Colombia.
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Hernandez, P.C., Wasserman, M. Do genes from the cholesterol synthesis pathway exist and express in Giardia intestinalis?. Parasitol Res 98, 194–199 (2006). https://doi.org/10.1007/s00436-005-0039-1
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DOI: https://doi.org/10.1007/s00436-005-0039-1