Dale R M, Wu M, Kiernan M C
Nucleic Acids Res. 1983 Mar 25;11(6):1673-85. doi: 10.1093/nar/11.6.1673.
Supercoiled mtDNAs were isolated from tobacco suspension culture cells and three of the smallest size classes (10.1, 20.2 and 30.3 kb) were characterized through denaturation, heteroduplex and restriction mapping. The 20.2 molecule was found to be a head-to-tail dimer of the 10.1 or X size class, while the 30.3 kb size class was found to contain two kinds of molecules, a head-to-tail trimer of X (X3) and a second molecule, ABC. X and ABC had a 118 +/- 35 bp region of homology, and both size classes shared a degree of homology with at least one other size class. Restriction maps of both the X and ABC molecules are presented and the possible origin and role of the many plant mtDNA size classes are discussed.
从烟草悬浮培养细胞中分离出超螺旋线粒体DNA（mtDNA），并通过变性、异源双链和限制性酶切图谱分析对三个最小尺寸类别的mtDNA（10.1、20.2和30.3 kb）进行了表征。发现20.2分子是10.1或X尺寸类别的头对头二聚体，而30.3 kb尺寸类别包含两种分子，一种是X的头对头三聚体（X3），另一种是ABC分子。X和ABC有一个118±35 bp的同源区域，并且这两个尺寸类别都与至少一个其他尺寸类别有一定程度的同源性。文中给出了X和ABC分子的限制性酶切图谱，并讨论了许多植物mtDNA尺寸类别的可能起源和作用。
