Fig. 6

Splicing of nad4 intron 1 was abolished in the fse5 mutant. Total RNA was extracted from nine-day-old seedlings, and random hexamer primers were used to synthetize first-strand cDNA. a, Transcript analysis of mitochondrial intron-containing genes in the WT (left) and fse5 mutant (right). OsActin1 was used as the internal control. Specific primers were used to amplify 9 transcripts (Wu et al. 2019). b, Schematic of nad4 precursor mRNA and RT-PCR analysis of three introns of nad4. nad4 precursor mRNA consists of 4 exons (E1-E4) and 3 introns. The black boxes indicate exons, and the curved lines represent introns. a, b, c, and m are fragments amplified by exon-exon flanking primers (Chen et al. 2017). Numbers of nucleic acids included by the introns and fragments are noted. M, DNA marker