Brown T A, Davies R W, Waring R B, Ray J A, Scazzochio C
Nature. 1983 Apr 21;302(5910):721-3. doi: 10.1038/302721a0.
The mitochondrial genome of the ascomycete Aspergillus nidulans possesses at least nine unidentified reading frames (URFs). Two of these are particularly interesting in that the amino acid sequences of the derived translation products are very similar in the N-terminal regions. The first 36 residues of the URFx gene product are repeated at the start of a second reading frame, URFA3, with only six mismatches. Despite this similarity in their amino-termini, the latter parts of URFx and URFA3 are completely different. Closer examination of the nucleotide sequences at the 5' ends of the two genes shows that the conserved peptides are part of a 300-base pair (bp) duplication within the mitochondrial genome. This duplication also includes the tRNA gene for asparagine and a conserved 116-bp intergenic region.
子囊菌构巢曲霉的线粒体基因组拥有至少九个未鉴定的阅读框（URF）。其中两个特别有趣，因为推导的翻译产物的氨基酸序列在N端区域非常相似。URFx基因产物的前36个残基在第二个阅读框URFA3的起始处重复，只有六个错配。尽管它们的氨基末端有这种相似性，但URFx和URFA3的后半部分完全不同。对这两个基因5'端核苷酸序列的仔细检查表明，保守肽是线粒体基因组内300碱基对（bp）重复的一部分。这种重复还包括天冬酰胺的tRNA基因和一个保守的116 bp基因间区域。
