Identification and expression analysis of cDNA encoding a chloroplast recombination protein REC1, the chloroplast RecA homologue in Chlamydomonas reinhardtii.
Chloroplasts of plant cells have their own genome, and a basic recombination protein homologous to the eubacterial RecA was suggested to be involved in the perpetuation of chloroplast DNA. A candidate cDNA sequence encoding the chloroplast RecA protein was identified from the Kazusa EST database for the unicellular green alga, Chlamydomonas reinhardtii (http://www.kazusa.or.jp/en/plant/chlamy/EST/). Analysis of the cDNA sequence identified an open reading frame (ORF) of 414 amino acids encoding a eubacteria-type RecA protein. Thus the corresponding gene was named REC1. The predicted protein contains an N-terminal extension that does not show any similarity with other RecA proteins. Transient expression of a REC1-sGFP (green fluorescent protein) fusion construct in tobacco cells has indicated that this N-terminal sequence functions as a transit peptide for import into chloroplasts. Since DNA-damaging reagents induced the REC1 mRNA, REC1 was suggested to have roles in DNA recombination and repair of the chloroplast DNA in C. reinhardtii.
Nakazato
Emi
E
Laboratory of Molecular Genetics, Department of Molecular Biology, Institute of Molecular and Cellular Biosciences, The University of Tokyo, Japan.
Fukuzawa
Hideya
H
Tabata
Satoshi
S
Takahashi
Hideo
H
Tanaka
Kan
K
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D016825:Chlamydomonas reinhardtii / Q000235:genetics*; D002736:Chloroplasts / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018742:DNA, Chloroplast / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism*; D011938:Rec A Recombinases / Q000235:genetics / Q000378:metabolism*; D011995:Recombination, Genetic / Q000235:genetics; D016415:Sequence Alignment; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism*
D018742:DNA, Chloroplast; D018076:DNA, Complementary; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins; D011938:Rec A Recombinases