The pentatricopeptide repeat gene OTP51 with two LAGLIDADG motifs is required for the cis-splicing of plastid ycf3 intron 2 in Arabidopsis thaliana.
Summary The Arabidopsis thaliana chloroplast contains 20 group-II introns in its genome, and seven known splicing factors are required for the splicing of overlapping subsets of 19 of them. We describe an additional protein (OTP51) that specifically promotes the splicing of the only group-II intron for which no splicing factor has been described previously. This protein is a pentatricopeptide repeat (PPR) protein containing two LAGLIDADG motifs found in group-I intron maturases in other organisms. Amino acids thought to be important for the homing endonuclease activity of other LAGLIDADG proteins are missing in this protein, but the amino acids described to be important for maturase activity are conserved. OTP51 is absolutely required for the splicing of ycf3 intron 2, and also influences the splicing of several other group-IIa introns. Loss of OTP51 has far-reaching consequences for photosystem-I and photosystem-II assembly, and for the photosynthetic fluorescence characteristics of mutant plants.
Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley 6009 WA, Australia.
Andéol Falcon
AF
de Longevialle
Luke
L
Hendrickson
Nicolas L
NL
Taylor
Etienne
E
Delannoy
Claire
C
Lurin
Murray
M
Badger
A Harvey
AH
Millar
Ian
I
Small
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D054628:Genome, Chloroplast; D018745:Genome, Plant; D007438:Introns; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D045331:Photosystem I Protein Complex / Q000235:genetics / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000235:genetics / Q000378:metabolism; D054730:Protein Interaction Domains and Motifs; D012326:RNA Splicing; D018749:RNA, Plant / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D020524:Thylakoids / Q000378:metabolism
D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D018742:DNA, Chloroplast; D018744:DNA, Plant; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D018749:RNA, Plant; C036483:T-DNA; D002734:Chlorophyll