Giron M L, de Thé H, Saïb A
CNRS UPR 9051, University of Paris VII, Hôpital Saint-Louis, 75475 Paris Cedex 10, France.
J Virol. 1998 Jun;72(6):4906-10. doi: 10.1128/JVI.72.6.4906-4910.1998.
Foamy viruses (spumaretroviruses) represent a retroviral genus which exhibits unusual features relating it to pararetroviruses. Previously, we reported the existence of a protein species harboring Env, Bel, and Bet epitopes in human foamy virus (HFV)-infected cells (M. L. Giron, F. Rozain, M. C. Debons-Guillemin, M. Canivet, J. Périès, and R. Emanoil-Ravier, J. Virol. 67:3596-3600, 1993). Here, we identify this protein as a 160-kDa Env-Bet fusion glycoprotein (gp160) translated from an mRNA species harboring a highly conserved splice site which deletes the membrane anchor domain of Env and fuses the env open reading frame with that of bel1/bet. While gp160 and Bet proteins were both secreted into the supernatant, only Bet was taken up by recipient cells. Since Bet plays a key role in the switch from lytic to chronic infection, secretion of Bet and gp160, together with cellular uptake of Bet, could be highly relevant for both immune response and development of HFV infection in vivo.
泡沫病毒(泡沫逆转录病毒)是逆转录病毒属,具有与副逆转录病毒相关的异常特征。此前,我们报道了在人类泡沫病毒(HFV)感染的细胞中存在一种含有Env、Bel和Bet表位的蛋白(M.L.吉龙、F.罗赞、M.C.德邦斯-吉耶曼、M.卡尼维、J.佩里埃和R.埃马诺伊尔-拉维耶,《病毒学杂志》67:3596 - 3600,1993年)。在此,我们鉴定该蛋白为一种160 kDa的Env - Bet融合糖蛋白(gp160),它由一种含有高度保守剪接位点的mRNA翻译而来,该剪接位点删除了Env的膜锚定结构域,并将env开放阅读框与bel1/bet的开放阅读框融合。虽然gp160和Bet蛋白都分泌到了上清液中,但只有Bet被受体细胞摄取。由于Bet在从裂解性感染向慢性感染的转变中起关键作用,Bet和gp160的分泌以及Bet的细胞摄取可能与体内HFV感染的免疫反应和发展高度相关。