Downard J S
J Bacteriol. 1987 Apr;169(4):1522-8. doi: 10.1128/jb.169.4.1522-1528.1987.
The expression of the ops gene, like that of the highly homologous and closely linked tps gene, is induced during development of the fruiting bacterium Myxococcus xanthus. The RNA products of the ops gene have been identified and compared with tps RNA. The ops RNA was observed in developmental cells only after spore formation had commenced, and it was necessary to use a sporulation-defective mutant strain or to disrupt spores to isolate this RNA. RNA from the ops gene was not observed in vegetative cells but was readily detected in cells subjected to glycerol-induced sporulation. In contrast, a large amount of developmental tps RNA was observed in cells well before sporulation had occurred; low levels of tps RNA were observed in vegetative cells; and only a slight increase in tps RNA was found during glycerol-induced sporulation. Several ops and tps RNAs were observed in this study, and the positions of these RNAs were mapped on the M. xanthus genome. The 5' ends of both the ops and tps RNAs mapped predominantly to positions about 50 bases upstream from the respective translational initiation sites. The 3' ends of RNAs from both genes were heterogeneous. The four ops RNAs were 620, 775, 845, and 1,230 bases in length, while the tps RNAs were 612, 695, 730, and 935 bases.
ops基因的表达，与高度同源且紧密连锁的tps基因一样，在粘细菌黄色粘球菌的发育过程中被诱导。ops基因的RNA产物已被鉴定，并与tps RNA进行了比较。ops RNA仅在孢子形成开始后才在发育细胞中被观察到，并且有必要使用孢子形成缺陷型突变菌株或破坏孢子来分离这种RNA。在营养细胞中未观察到来自ops基因的RNA，但在甘油诱导的孢子形成的细胞中很容易检测到。相比之下，在孢子形成发生之前很久就在细胞中观察到大量发育性tps RNA；在营养细胞中观察到低水平的tps RNA；并且在甘油诱导的孢子形成过程中仅发现tps RNA略有增加。在本研究中观察到了几种ops和tps RNA，并将这些RNA的位置定位在黄色粘球菌基因组上。ops和tps RNA的5'端主要定位在各自翻译起始位点上游约50个碱基的位置。两个基因的RNA的3'端是异质的。四种ops RNA的长度分别为620、775、845和1230个碱基，而tps RNA的长度分别为612、695、730和935个碱基。
