Yu S F, Baldwin D N, Gwynn S R, Yendapalli S, Linial M L
Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98104, USA.
Science. 1996 Mar 15;271(5255):1579-82. doi: 10.1126/science.271.5255.1579.
Human foamy virus (HFV) is the prototype of the Spumavirus genus of Retroviridae. In all other retroviruses, the pol gene products, including reverse transcriptase, are synthesized as Gag-Pol fusion proteins and are cleaved to functional enzymes during viral budding or release. In contrast, the Pol protein of HFV is translated from a spliced messenger RNA and lacks Gag domains. Infectious HFV particles contain double-stranded DNA similar in size to full-length provirus, suggesting that reverse transcription has taken place in viral particles before new rounds of infection, reminiscent of hepadnaviruses. These data suggest that foamy viruses possess a replication pathway containing features of both retroviruses and hepadnaviruses but distinct from both.
人类泡沫病毒（HFV）是逆转录病毒科泡沫病毒属的原型。在所有其他逆转录病毒中，包括逆转录酶在内的pol基因产物是以Gag-Pol融合蛋白的形式合成的，并在病毒出芽或释放过程中被切割成功能性酶。相比之下，HFV的Pol蛋白是从剪接后的信使RNA翻译而来，并且缺乏Gag结构域。具有感染性的HFV颗粒含有与全长前病毒大小相似的双链DNA，这表明逆转录在新一轮感染之前已在病毒颗粒中发生，这让人联想到嗜肝DNA病毒。这些数据表明，泡沫病毒拥有一种复制途径，该途径兼具逆转录病毒和嗜肝DNA病毒的特征，但又与两者不同。
