Comparative large scale characterization of plant versus mammal proteins reveals similar and idiosyncratic N-α-acetylation features.
N-terminal modifications play a major role in the fate of proteins in terms of activity, stability, or subcellular compartmentalization. Such modifications remain poorly described and badly characterized in proteomic studies, and only a few comparison studies among organisms have been made available so far. Recent advances in the field now allow the enrichment and selection of N-terminal peptides in the course of proteome-wide mass spectrometry analyses. These targeted approaches unravel as a result the extent and nature of the protein N-terminal modifications. Here, we aimed at studying such modifications in the model plant Arabidopsis thaliana to compare these results with those obtained from a human sample analyzed in parallel. We applied large scale analysis to compile robust conclusions on both data sets. Our data show strong convergence of the characterized modifications especially for protein N-terminal methionine excision, co-translational N-α-acetylation, or N-myristoylation between animal and plant kingdoms. Because of the convergence of both the substrates and the N-α-acetylation machinery, it was possible to identify the N-acetyltransferases involved in such modifications for a small number of model plants. Finally, a high proportion of nuclear-encoded chloroplast proteins feature post-translational N-α-acetylation of the mature protein after removal of the transit peptide. Unlike animals, plants feature in a dedicated pathway for post-translational acetylation of organelle-targeted proteins. The corresponding machinery is yet to be discovered.
CNRS, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France.
Willy V
WV
Bienvenut
David
D
Sumpton
Aude
A
Martinez
Sergio
S
Lilla
Christelle
C
Espagne
Thierry
T
Meinnel
Carmela
C
Giglione
D000107:Acetylation; D000123:Acetyltransferases / Q000737:chemistry / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism*; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D010446:Peptide Fragments / Q000737:chemistry; D010802:Phylogeny; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D020543:Proteome / Q000737:chemistry / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
D029681:Arabidopsis Proteins; D010446:Peptide Fragments; D020543:Proteome; D000123:Acetyltransferases