Mapping of two O-GlcNAc modification sites in the capsid protein of the potyvirus Plum pox virus

• Published in: FEBS letters 2006-10, Vol.580 (25), p.5822-5828
• Main Authors: Pérez, José de Jesús, Juárez, Silvia, Chen, Dinghu, Scott, Cheryl L., Hartweck, Lynn M., Olszewski, Neil E., García, Juan Antonio
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Amino Acid Substitution; Base Sequence; Binding Sites; Capsid protein; Capsid Proteins - chemistry; Capsid Proteins - genetics; Capsid Proteins - metabolism; days post infection; DNA, Viral - genetics; dpi; Glycosylation; MALDI-TOF; Matrix-assisted Laser Desorption/Ionization-Time of Flight; Molecular Sequence Data; Mutagenesis, Site-Directed; Nicotiana - virology; Nicotiana clevelandii; O-GlcNAc; O-GlcNAc transferase; O-GlcNAcylation; O-glycosylation; O-Linked N-acetylglucosamination; O-linked β-N-acetylglucosamine; OGT; Plant Diseases - virology; Plum pox virus; Plum Pox Virus - chemistry; Plum Pox Virus - genetics; Plum Pox Virus - pathogenicity; Potyvirus; Protein Processing, Post-Translational; Prunus; Prunus - virology; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; SEC; SECRET AGENT; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; SPINDLY; SPY; Threonine - chemistry
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/j.febslet.2006.09.041

A large number of O-linked N-acetylglucosamine ( O-GlcNAc) residues have been mapped in vertebrate proteins, however targets of O-GlcNAcylation in plants still have not been characterized. We show here that O-GlcNAcylation of the N-terminal region of the capsid protein of Plum pox virus resembles that of animal proteins in introducing O-GlcNAc monomers. Thr-19 and Thr-24 were specifically O-GlcNAcylated. These residues are surrounded by amino acids typical of animal O-GlcNAc acceptor sites, suggesting that the specificity of O-GlcNAc transferases is conserved among plants and animals. In laboratory conditions, mutations preventing O-GlcNAcylation of Thr-19 and Thr-24 did not have noticeable effects on PPV competence to infect Prunus persicae or Nicotiana clevelandii. However, the fact that Thr-19 and Thr-24 are highly conserved among different PPV strains suggests that their O-GlcNAc modification could be relevant for efficient competitiveness in natural conditions.