Evolutionary transfer of the chloroplast tufA gene to the nucleus.
Evolutionary gene transfer is a basic corollary of the now widely accepted endosymbiotic theory, which proposes that mitochondria and chloroplasts originated from once free-living eubacteria. The small organellar chromosomes are remnants of larger bacterial genomes, with most endosymbiont genes having been either transferred to the nucleus soon after endosymbiosis or lost entirely, with some being functionally replaced by pre-existing nuclear genes. Several lines of evidence indicate that relocation of some organelle genes could have been more recent. These include the abundance of non-functional organelle sequences of recent origin in nuclear DNA, successful artificial transfer of functional organelle genes to the nucleus, and several examples of recently lost organelle genes, although none of these is known to have been replaced by a nuclear homologue that is clearly of organellar ancestry. We present gene sequence and molecular phylogenetic evidence for the transfer of the chloroplast tufA gene to the nucleus in the green algal ancestor of land plants.
Baldauf
S L
SL
Department of Biology, University of Michigan, Ann Arbor 48109.
Palmer
J D
JD
D000595:Amino Acid Sequence; D001483:Base Sequence; D005075:Biological Evolution; D002467:Cell Nucleus / Q000378:metabolism*; D000460:Chlorophyta / Q000235:genetics; D002736:Chloroplasts / Q000378:metabolism*; D004247:DNA / Q000235:genetics*; D008969:Molecular Sequence Data; D009491:Neurospora / Q000235:genetics; D009693:Nucleic Acid Hybridization; D010444:Peptide Elongation Factor Tu / Q000235:genetics*; D010944:Plants / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid
D004247:DNA; D010444:Peptide Elongation Factor Tu