Two intervening sequences in the ATPase subunit 6 gene of Neurospora crassa. A short intron (93 base-pairs) and a long intron that is stable after excision.

A 3590 base-pair region of the mitochondrial genome of Neurospora crassa, including the gene for ATPase subunit 6 (oli2), has been sequenced. The oli2 gene is interrupted by two intervening sequences. The first intron, situated after the third codon of the gene, is 93 base-pairs long; two-thirds of this intron consist of a palindromic sequence. The second intron is 1370 base-pairs long and contains an extended open reading frame that is continuous and in frame with the upstream exon sequence. This intron has structural homology with most other fungal mitochondrial introns. Transcript analysis has yielded a complex pattern of RNA species and demonstrated that the second intron is quite stable after excision. An unknown reading frame (homologous to reading frames of other mitochondrial genomes) is located 1000 base-pairs upstream from the oli2 coding sequence.