Isolation of virulence genes directing surface glycosyl-phosphatidylinositol synthesis by functional complementation of Leishmania.

AUTOR(ES)

Ryan, K A

RESUMO

Trypanosomatid parasites of the genus Leishmania cause a spectrum of widespread tropical diseases. In the vertebrate host they reside within the macrophage phagolysosome; however, the mechanisms employed in this remarkable survival strategy are not well understood. Recent advances in the molecular genetics of these parasites prompted us to develop methods of functional genetic complementation in Leishmania and apply them to the isolation of genes involved in the biosynthesis of the virulence determinant lipophosphoglycan, an abundant glycosyl-phosphatidylinositol-anchored polysaccharide. LPG1, the gene product identified by complementation of the R2D2 mutant, appears to be a glycosyltransferase responsible for the addition of galactofuranosyl residues to the nascent lipophosphoglycan chain. As galactofuranose is not found in mammalian cells, inhibition of the addition of this sugar could be exploited for chemotherapy. Overall, the success of the functional complementation approach opens the way to the identification of a variety of genes involved in pathogenesis and parasitism.

Documentos Relacionados

• Evidence for glycosyl-phosphatidylinositol anchoring of Toxoplasma gondii major surface antigens.
• Biosynthesis of glycosyl-phosphatidylinositol lipids in Trypanosoma brucei: involvement of mannosyl-phosphoryldolichol as the mannose donor.
• Apical Localization of the Coxsackie-Adenovirus Receptor by Glycosyl-Phosphatidylinositol Modification Is Sufficient for Adenovirus-Mediated Gene Transfer through the Apical Surface of Human Airway Epithelia
• Stimulation of glycogen synthesis by insulin in human erythroleukemia cells requires the synthesis of glycosyl-phosphatidylinositol.
• Complementary DNA for the folate binding protein correctly predicts anchoring to the membrane by glycosyl-phosphatidylinositol.