Impact of low temperature on splicing of atypical group II introns in wheat mitochondria.
To investigate the impact of cold on group II intron splicing, we compared the physical forms of excised mitochondrial introns from wheat embryos germinated at room temperature and 4°C. For introns which deviate from the conventional branchpoint structure, we observed predominantly heterogeneous circularized introns in the cold rather than linear polyadenylated forms arising from a hydrolytic pathway as seen at room temperature. In addition, intron-containing precursors are elevated relative to mature mRNAs upon cold treatment. Our findings indicate that low temperature growth not only reduces splicing efficiency, but also shifts the splicing biochemistry of atypical group II introns to novel, yet productive, pathways.
Biology Department, University of Ottawa, Ottawa K1N 6N5, Canada.
Stephen J
SJ
Dalby
Linda
L
Bonen
D001483:Base Sequence; D017931:DNA Primers; D007438:Introns; D008928:Mitochondria / Q000235:genetics*; D012326:RNA Splicing; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds; D014908:Triticum / Q000235:genetics*
D017931:DNA Primers
Cold; Evolution; Intron; Mitochondria; Ribozyme; Splicing