Presence of a latent mitochondrial targeting signal in gene on mitochondrial genome.
Organelles, such as mitochondria and chloroplasts, are derived from endosymbionts. Gene transfer events from organelles to the nucleus have occurred over evolutionary time. In the case that a transferred gene in the nucleus needs to go back to the original organelle, it must obtain targeting information for sorting its protein to that organelle. Here, we reveal that the genes for the ribosomal proteins L2 and S4 in the Arabidopsis thaliana mitochondrial (mt) genome contain information for protein targeting into the mitochondria. Similarly, the genes for the ribosomal proteins L2 and S19 in the Oryza sativa mt genome contain information for protein targeting into mitochondria. These results suggest that targeting information already existed in each gene in the plant mt genome before the transfer event to the nucleus occurred. We provide new insights into the timing of the appearance of targeting signals in evolution.
Minoru
M
Ueda
Masaru
M
Fujimoto
Shin-Ichi
S
Arimura
Nobuhiro
N
Tsutsumi
Koh-Ichi
K
Kadowaki
D017360:Arabidopsis; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000235:genetics; D050259:Genes, Mitochondrial; D017343:Genes, Plant; D018745:Genome, Plant; D012275:Oryza; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D021381:Protein Transport / Q000235:genetics*; D011995:Recombination, Genetic; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; D010940:Plant Proteins; D012269:Ribosomal Proteins; C029466:ribosomal protein L2; C040343:ribosomal protein S19; C031798:ribosomal protein S4