Figure 1.

oxt6-mediated suppression of cell death in mips1. A, Suppression of mips1-mediated cell death in the mips1 oxt6 background and restoration of the cell death phenotype through the complementation of mips1 oxt6 with the smaller of the two OXT6-derived mRNAs. Plants were grown 1 week in vitro and then 14 d in SD conditions in soil and photographed 5 d after transfer to LD conditions. Bar = 1 cm. B, Ion leakage assays, with means and sd calculated from six discs per treatment with three replicates within an experiment in SD and LD conditions. The asterisk denotes a significantly different value according to Student’s t test (P < 0.002). C, Trypan blue staining of wild-type, mips1, oxt6, and mips1 oxt6 leaves. Bars = 2 mm. D, Schematic representation of the OXT6 (AT1G30460) gene structure. Light gray boxes indicate the exons present in the smaller of the two transcripts encoded by this gene, while black boxes represent additional exons present in the larger of the two OXT6-encoded RNAs. The sequence represented by the small dark gray box is absent in the larger RNA (alternative splicing indicated by the dashed line). The structures of the small (CPSF30) and the larger (CPSF30-YT521-B) RNAs are depicted beneath the illustration of the genomic DNA. The position of the T-DNA insertion (Zhang et al., 2008) in the oxt6 mutant is indicated on the genomic DNA.