German Cancer Research Center (DKFZ), Research Program Infection and Cancer, Heidelberg, Germany.
Virology. 2012 Mar 15;424(2):138-46. doi: 10.1016/j.virol.2011.12.017. Epub 2012 Jan 20.
Defined host-encoded feline APOBEC3 (feA3) cytidine deaminases efficiently restrict the replication and spread of exogenous retroviruses like Feline Immunodeficiency Virus (FIV) and Feline Foamy Virus (FFV) which developed different feA3 counter-acting strategies. Here we characterize the molecular interaction of FFV proteins with the diverse feA3 proteins. The FFV accessory protein Bet is the virus-encoded defense factor which is shown here to bind all feA3 proteins independent of whether they restrict FFV, a feature shared with FIV Vif that induces degradation of all feA3s including those that do not inactivate FIV. In contrast, only some feA3 proteins bind to FFV Gag, a pattern that in part reflects the restriction pattern detected. Additionally, one-domain feA3 proteins can homo- and hetero-dimerize in vitro, but a trans-dominant phenotype of any of the low-activity feA3 forms on FFV restriction by one of the highly-active feA3Z2 proteins was not detectable.
定义宿主编码的猫 APOBEC3（feA3）胞嘧啶脱氨酶能够有效地限制外源逆转录病毒的复制和传播，如猫免疫缺陷病毒（FIV）和猫泡沫病毒（FFV），它们发展了不同的 feA3 对抗策略。在这里，我们描述了 FFV 蛋白与不同 feA3 蛋白的分子相互作用。FFV 的辅助蛋白 Bet 是病毒编码的防御因子，它被证明可以与所有 feA3 蛋白结合，而不管它们是否限制 FFV，这一特性与 FIV 的 Vif 共享，Vif 诱导所有 feA3 的降解，包括那些不能使 FIV 失活的 feA3。相比之下，只有一些 feA3 蛋白与 FFV Gag 结合，这种模式部分反映了检测到的限制模式。此外，一结构域 feA3 蛋白可以在体外发生同源和异源二聚化，但在高活性 feA3Z2 蛋白之一限制 FFV 时，任何低活性 feA3 形式的反式显性表型都无法检测到。
