Schardl C L, Pring D R, Lonsdale D M
Cell. 1985 Nov;43(1):361-8. doi: 10.1016/0092-8674(85)90041-8.
The mitochondrial genome of the S-type male-sterile cytoplasm of maize appears to be a collection of linear DNA molecules that are maintained by two linear episomal DNA species, S1 (6397 bp) and S2 (5453 bp), recombining with larger circular molecules. The M825 inbred nuclear genotype promotes a high frequency of spontaneous fertile mutants. Where the mutation is maternally inherited, analysis of the mitochondrial DNA reveals that the S1 and S2 episomes and all associated linear molecules have been lost. Integrated copies of the S1 and S2 episomes are retained, though part of one of the two terminal inverted repeats of the integrated S2 sequence has been deleted in all revertants studied. This deletion appears to correlate with the absence of the S2-URF-1 transcript.
玉米S型雄性不育细胞质的线粒体基因组似乎是由两个线性附加型DNA分子S1（6397碱基对）和S2（5453碱基对）与较大的环状分子重组而维持的线性DNA分子集合。M825近交核基因型促进了高频自发可育突变体的产生。当突变是母系遗传时，线粒体DNA分析表明S1和S2附加体以及所有相关的线性分子都已丢失。S1和S2附加体的整合拷贝得以保留，不过在所有研究的回复体中，整合的S2序列的两个末端反向重复之一的一部分已被删除。这种缺失似乎与S2-URF-1转录本的缺失相关。
