Angata K, Ogawa S, Yanagisawa K, Tanaka Y
Institute of Biological Sciences, University of Tsukuba, Ibaraki, Japan.
Gene. 1995 Feb 3;153(1):49-55. doi: 10.1016/0378-1119(94)00732-8.
A 547-bp group-I intron belonging to subgroup IA1 was found near the 3' end of the large subunit ribosomal RNA-encoding gene (LSUrRNA) in the mitochondrial (mt) DNA of the cellular slime mold Dictyostelium discoideum. This intron was inserted in a highly conserved stretch within the sequence that encodes the peptidyl transferase center domain V in the corresponding region of the Escherichia coli LSUrRNA. Interestingly, the insertion site of the intron is the same as that of the So.LSU.2 intron of the green alga, Scenedesmus obliquus, mt DNA and the Pw.LSU.2 intron of the colorless alga, Prototheca wickerhamii, mt DNA. The intron could self-splice in vitro at a concentration higher than 20 mM MgCl2. Polymerase chain reaction analysis showed the possible existence of an intron similar to that of D. discoideum LSUrRNA in another cellular slime mold, Polysphondylium pallidum (CK-8), but not in D. mucoroides (Dm7 and Dm11).
在细胞黏菌盘基网柄菌的线粒体（mt）DNA中，在编码大亚基核糖体RNA的基因（LSUrRNA）的3'端附近发现了一个属于IA1亚组的547个碱基对的I类内含子。该内含子插入到大肠杆菌LSUrRNA相应区域中编码肽基转移酶中心结构域V的序列内的一个高度保守区域。有趣的是，该内含子的插入位点与绿藻斜生栅藻mt DNA的So.LSU.2内含子和无色藻威克汉姆原甲藻mt DNA的Pw.LSU.2内含子的插入位点相同。该内含子在体外MgCl2浓度高于20 mM时可自我剪接。聚合酶链反应分析表明，在另一种细胞黏菌苍白聚孢霉（CK - 8）中可能存在与盘基网柄菌LSUrRNA的内含子相似的内含子，但在毛霉状网柄菌（Dm7和Dm11）中不存在。
