Cytoplasmic N-terminal protein acetylation is required for efficient photosynthesis in Arabidopsis.
The Arabidopsis atmak3-1 mutant was identified on the basis of a decreased effective quantum yield of photosystem II. In atmak3-1, the synthesis of the plastome-encoded photosystem II core proteins D1 and CP47 is affected, resulting in a decrease in the abundance of thylakoid multiprotein complexes. DNA array-based mRNA analysis indicated that extraplastid functions also are altered. The mutation responsible was localized to AtMAK3, which encodes a homolog of the yeast protein Mak3p. In yeast, Mak3p, together with Mak10p and Mak31p, forms the N-terminal acetyltransferase complex C (NatC). The cytoplasmic AtMAK3 protein can functionally replace Mak3p, Mak10p, and Mak31p in acetylating N termini of endogenous proteins and the L-A virus Gag protein. This result, together with the finding that knockout of the Arabidopsis MAK10 homolog does not result in obvious physiological effects, indicates that AtMAK3 function does not require NatC complex formation, as it does in yeast. We suggest that N-acetylation of certain chloroplast precursor protein(s) is necessary for the efficient accumulation of the mature protein(s) in chloroplasts.
Pesaresi
Paolo
P
Abteilung für Pflanzenzüchtung und Ertragsphysiologie, Max-Planck-Institut für Züchtungsforschung, D-50829 Köln, Germany.
Gardner
Nora A
NA
Masiero
Simona
S
Dietzmann
Angela
A
Eichacker
Lutz
L
Wickner
Reed
R
Salamini
Francesco
F
Leister
Dario
D
D000107:Acetylation; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001191:Arylamine N-Acetyltransferase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D005816:Genetic Complementation Test; D046911:Macromolecular Substances; D008928:Mitochondria / Q000378:metabolism; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes; D009154:Mutation; D010641:Phenotype; D010788:Photosynthesis; D014176:Protein Biosynthesis; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D020524:Thylakoids / Q000378:metabolism
D029681:Arabidopsis Proteins; D018744:DNA, Plant; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D029701:Saccharomyces cerevisiae Proteins; D001191:Arylamine N-Acetyltransferase