Jaquenoud, Malika Pagac, Martin Signorell, Aita Benghezal, Mohammed Jelk, Jennifer Bütikofer, Peter Conzelmann, Andreas 2007-12-07 Glycosylphosphatidylinositol (GPI) lipids of <i>Trypanosoma brucei</i> undergo lipid remodelling, whereby longer fatty acids on the glycerol are replaced by myristate (C14:0). A similar process occurs on GPI proteins of <i>Saccharomyces cerevisiae</i> where Per1p first deacylates, Gup1p subsequently reacylates the anchor lipid, thus replacing a shorter fatty acid by C26:0. Heterologous expression of the <i>GUP1</i> homologue of <i>T. bruce</i>i in <i>gup1</i>Δ yeast cells partially normalizes the <i>gup1</i>Δ phenotype and restores the transfer of labelled fatty acids from Coenzyme A to <i>lyso</i>-GPI proteins in a newly developed microsomal assay. In this assay, the Gup1p from <i>T. brucei</i> (tbGup1p) strongly prefers C14:0 and C12:0 over C16:0 and C18:0, whereas yeast Gup1p strongly prefers C16:0 and C18:0. This acyl specificity of tbGup1p closely matches the reported specificity of the reacylation of free <i>lyso</i>-GPI lipids in microsomes of <i>T. brucei</i>. Depletion of tbGup1p in trypanosomes by RNAi drastically reduces the rate of myristate incorporation into the <i>sn</i>-2 position of <i>lyso</i>-GPI lipids. Thus, tbGup1p is involved in the addition of myristate to <i>sn</i>-2 during GPI remodelling in <i>T. brucei</i> and can account for the fatty acid specificity of this process. tbGup1p can act on GPI proteins as well as on GPI lipids. application/pdf https://folia.unifr.ch/global/documents/300683 https://folia.unifr.ch/documents/300683/files/conzelmann_ght.pdf https://folia.unifr.ch/documents/300683/files/conzelmann_ght_sm.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1111/j.1365-2958.2007.06043.x info:eu-repo/semantics/openAccess License undefined Molecular Microbiology. - 2008, vol. 67, no. 1, p. 202-212 info:eu-repo/classification/udc/57 The <i>Gup1</i> homologue of <i>Trypanosoma brucei</i> is a GPI glycosylphosphatidylinositol remodelase http://purl.org/coar/resource_type/c_6501