Glushkova I V, Gvozdev V A
Genetika. 1991 Mar;27(3):404-10.
The genomes of laboratory stocks and natural population of Drosophila melanogaster contain 8-12 copies of retrotransposon MDG3 detected by in situ hybridization. Construction of genotypes with decreased MDG3 copy number using X-chromosome and chromosome 3 free of MDG3 copies results in appearance of hybrid genomes carrying up to 7-10 copies, instead of 2-4 copies expected. New MDG3 copies are detected in different genome regions, including the 42B hot spot of their location. The chromosomes, where new clusters of MDG3 were observed, carry conserved "parental pattern" of MDG1 arrangement. The data obtained suggest the existence of genomic mechanism for maintenance of retrotransposon copy number on a definite level.
通过原位杂交检测发现，黑腹果蝇实验室品系和自然种群的基因组中含有8 - 12个反转录转座子MDG3拷贝。利用不含MDG3拷贝的X染色体和3号染色体构建MDG3拷贝数减少的基因型，结果出现了携带多达7 - 10个拷贝的杂交基因组，而不是预期的2 - 4个拷贝。在不同的基因组区域检测到新的MDG3拷贝，包括其定位的42B热点区域。观察到新MDG3簇的染色体带有MDG1排列的保守“亲本模式”。所获得的数据表明存在一种基因组机制，可将反转录转座子拷贝数维持在一定水平。
