Lozovskaya E R, Hartl D L, Petrov D A
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
Curr Opin Genet Dev. 1995 Dec;5(6):768-73. doi: 10.1016/0959-437x(95)80009-t.
Transposable elements are a major source of genetic change, including the creation of novel genes, the alteration of gene expression in development, and the genesis of major genomic rearrangements. They are ubiquitous among contemporary organisms and probably as old as life itself. The long coexistence of transposable elements in the genome would be expected to be accompanied by host-element coevolution. Indeed, the important role of host factors in the regulation of transposable elements has been illuminated by recent studies of several systems in Drosophila. These include host factors that regulate the P element, a host mutation that renders the genome permissive for gypsy mobilization and infection, and newly induced mutations that affect the expression of transposon insertion mutations. The finding of a type of hybrid dysgenesis in D. virilis, in which multiple unrelated transposable elements are mobilized simultaneously, may also be relevant to host-factor regulation of transposition.
转座元件是遗传变化的主要来源，包括新基因的产生、发育过程中基因表达的改变以及主要基因组重排的发生。它们在当代生物中无处不在，可能与生命本身一样古老。转座元件在基因组中的长期共存预计会伴随着宿主与元件的共同进化。事实上，果蝇中几个系统的最新研究揭示了宿主因子在转座元件调控中的重要作用。这些包括调控P元件的宿主因子、使基因组对gypsy转座和感染具有许可性的宿主突变，以及影响转座子插入突变表达的新诱导突变。在粗壮果蝇中发现的一种杂种不育现象，即多个不相关的转座元件同时被激活，这也可能与宿主因子对转座的调控有关。
