Pays E, Van Assel S, Laurent M, Darville M, Vervoort T, Van Meirvenne N, Steinert M
Cell. 1983 Sep;34(2):371-81. doi: 10.1016/0092-8674(83)90371-9.
Expression of the gene coding for the trypanosome AnTat 1.1 surface antigen is linked to the duplicative transposition of a basic copy (BC) of this gene to an expression site. In two trypanosome clones successively derived from AnTat 1.1 (AnTat 1.10 and AnTat 1.1B) we found evidence that gene conversions are involved in the transformation of the AnTat 1.1 transposed element into the two new surface antigen coding sequences. Although the three resultant mRNAs--AnTat 1.1, 1.10, and 1.1B--are different, they still share large homologies. Two of them, AnTat 1.1 and 1.1B, code for surface coats that are indistinguishable by conventional serological techniques, whereas AnTat 1.10 has been found different by the same methods. The three genomic rearrangements involve two of the five members of the AnTat 1.1 gene family. These two members are both located in unstable telomeric regions similar to the expression site, each in a different orientation with respect to the DNA terminus. We have concluded that the duplicative transposition is achieved by a gene conversion that may affect variable lengths of the same silent genes, and that different members of the same surface antigen gene family can contribute to the diversification of the antigen repertoire.
锥虫AnTat 1.1表面抗原编码基因的表达与该基因的一个基本拷贝（BC）向一个表达位点的重复转座有关。在两个相继源自AnTat 1.1的锥虫克隆（AnTat 1.10和AnTat 1.1B）中，我们发现有证据表明基因转换参与了将AnTat 1.1转座元件转化为两个新的表面抗原编码序列的过程。尽管产生的三种mRNA——AnTat 1.1、1.10和1.1B——不同，但它们仍有很大的同源性。其中两种，AnTat 1.1和1.1B，编码的表面被膜用传统血清学技术无法区分，而用同样的方法发现AnTat 1.10有所不同。这三种基因组重排涉及AnTat 1.1基因家族五个成员中的两个。这两个成员都位于类似于表达位点的不稳定端粒区域，相对于DNA末端，各自方向不同。我们得出结论，重复转座是通过一种可能影响相同沉默基因不同长度的基因转换实现的，并且同一表面抗原基因家族的不同成员可促成抗原库的多样化。
