Thon G, Baltz T, Giroud C, Eisen H
Fred Hutchinson Cancer Research Center, Seattle, Washington 98104.
Genes Dev. 1990 Aug;4(8):1374-83. doi: 10.1101/gad.4.8.1374.
Combinatorial processes increase the diversity of variable surface glycoproteins (VSGs) expressed by Trypanosoma equiperdum. We show here that a single telomeric pseudogene provides the 3' portion of three distinct T. equiperdum VSG genes by recombination with different 5' donor pseudogenes. Regions of sequence homology among the pseudogenes determine the sites of recombination in the formation of the expressed copies. This suggests that the recombination between any given basic copy (BC) and the expression-linked copy (ELC) depends on their sharing homology. We present evidence that this is the case and propose that such rules account for the order of expression of the VSGs. These results demonstrate how homologous recombination can generate an ordered sequence of gene expression.
组合过程增加了马媾疫锥虫表达的可变表面糖蛋白（VSG）的多样性。我们在此表明，单个端粒假基因通过与不同的5'供体假基因重组，为三个不同的马媾疫锥虫VSG基因提供3'部分。假基因之间的序列同源区域决定了表达拷贝形成过程中的重组位点。这表明任何给定的基本拷贝（BC）与表达连接拷贝（ELC）之间的重组取决于它们共享的同源性。我们提供的证据表明情况确实如此，并提出这样的规则解释了VSG的表达顺序。这些结果证明了同源重组如何产生有序的基因表达序列。
