Hehlmann R, Brack-Werner R, Leib-Mösch C
Medizinische Poliklinik, Universitat Munchen.
Leukemia. 1988 Dec;2(12 Suppl):167S-177S.
One of the unique features of retroviruses is their ability to integrate their genetic information in the genomes of their host cells, including the germ line, and to persist there as so-called proviruses. Proviruses which are contained in the germ line of a given species and are inherited from generation to generation like cellular genes are called endogenous retroviruses (for review see 1). Although the function or bioiological role of endogenous retroviruses still remains to be elucidated, they have been detected in almost all vertebrate species examined. The most relevant properties of endogenous, genetically transmitted retroviruses are summarized in Table 1. Endogenous retroviruses persist in cellular DNA, are transmitted through the germ line, and possess a transposon-like structure (2) which enables them to integrate at any position of the cellular genome. Endogenous retroviruses can be activated by certain chemicals such as mutagens/carcinogens or mitogens, by radiation, and by other mechanisms such as DNA-viruses or physiological processes (e.g. aging) to express antigens or to form infectious virus particles. Their biological relevance is unknown but may include involvement in physiological processes such as protection against superinfection by related retroviruses, similar to observations made with exogenous retroviruses in some animal model systems.
逆转录病毒的独特特征之一是它们能够将自身的遗传信息整合到宿主细胞的基因组中，包括生殖细胞系，并以所谓的前病毒形式持续存在于其中。存在于特定物种生殖细胞系中并像细胞基因一样代代相传的前病毒被称为内源性逆转录病毒（综述见1）。尽管内源性逆转录病毒的功能或生物学作用仍有待阐明，但在几乎所有已检测的脊椎动物物种中都发现了它们。内源性、可遗传传播的逆转录病毒的最相关特性总结于表1中。内源性逆转录病毒存在于细胞DNA中，通过生殖细胞系传播，并具有类似转座子的结构（2），这使其能够整合到细胞基因组的任何位置。内源性逆转录病毒可被某些化学物质如诱变剂/致癌物或促细胞分裂剂、辐射以及其他机制如DNA病毒或生理过程（如衰老）激活，从而表达抗原或形成感染性病毒颗粒。它们的生物学相关性尚不清楚，但可能包括参与生理过程，如防止相关逆转录病毒的重复感染，这类似于在一些动物模型系统中对外源性逆转录病毒的观察结果。
