Wong W M, Abrahamson J L, Nazar R N
Proc Natl Acad Sci U S A. 1984 Mar;81(6):1768-70. doi: 10.1073/pnas.81.6.1768.
The genome of a thermophilic fungus, Thermomyces lanuginosus, contains a tandemly arranged cluster of sequences that are approximately equal to 50% homologous with the cytoplasmic 5S RNA and that are selectable by hybridization techniques. Unlike typical pseudogenes, these sequences are not truncated; rather, they bear a limited sequence homology with the entire length of the 5S RNA and are oriented end to end without significant intervening sequences. We suggest that these are gene relics that were duplicated by a rolling circle-like mechanism and that have evolutionarily drifted to become gene spacers. Accordingly, we raise the possibility that this offers a fortuitous glimpse at the origins for many of the gene spacers in the eukaryotic genome.
嗜热真菌羊毛嗜热丝孢菌（Thermomyces lanuginosus）的基因组包含一个串联排列的序列簇，这些序列与细胞质5S RNA约有50%的同源性，并且可以通过杂交技术进行筛选。与典型的假基因不同，这些序列没有被截断；相反，它们与5S RNA的全长具有有限的序列同源性，并且首尾相连排列，中间没有明显的间隔序列。我们认为这些是通过类似滚环机制复制的基因遗迹，并且在进化过程中已经漂移成为基因间隔区。因此，我们提出这样一种可能性，即这为偶然了解真核基因组中许多基因间隔区的起源提供了一个机会。
