Protein fatty acylation affects several aspects of Toxoplasma gondii biology

CABALLERO, MC; ALONSO, AM; CORVI, MM

Buenos Aires

Congreso; XXVII Annual Meeting Sociedad Argentina de Protozoologia; 2015

SAP

Proteinfatty acylation refers the covalent modification of proteins by long chainfatty acids. This modification plays key roles in cellular signaling pathways,in mediating subcellular targeting and in protein-protein interactions requiredfor activity. It is divided into two categories: myristoylation andpalmitoylation. N-myristoylation involves the co- or post-translationalattachment of myristate to an N-terminal glycine residue of a protein via astable amide linkage. We obtained data demonstrating that T. gondii expresses one N-myristoyl transferase, enzyme responsiblefor this modification. Furthermore, myristoylated proteins are predicted to beinvolved in important events for this parasite such as calcium homeostasis andkinase activity regulation which are critical for invasion and gliding. Inparallel, protein palmitoylation typically refers to the covalent attachment ofpalmitate to cysteine residues via a thioester linkage. Our experimentalpalmitoylome shows that most of thepalmitoylated proteins cluster into groups including metabolic andenergy-related processes and protein translation. However, it is evident thatthe modification affects the majority of cellular functions since we were ableto identify proteins involved in signaling, gliding motility, transcription andtranslation. From our data we can conclude that protein fatty acylation is awidespread modification that affects vital processes of this parasite