APOBEC3 Deaminases Induce Hypermutation in Human Papillomavirus 16 DNA upon Beta Interferon Stimulation
APOBEC3 Deaminases Induce Hypermutation in Human Papillomavirus 16 DNA upon Beta Interferon Stimulation
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DOI：
10.1128/jvi.03091-13
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发表时间：
2014-01-01
影响因子：
5.4
通讯作者：
Muramatsu, Masamichi
中科院分区：
文献类型：
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作者：
Wang, Zhe;Wakae, Kousho;Muramatsu, Masamichi
载脂蛋白B信使核糖核酸编辑催化多肽3(APOBEC3)蛋白是干扰素(干扰素)诱导的抗病毒因子，通过诱导病毒DNA胞苷(C)到尿嘧啶(U)突变和抑制逆转录来对抗各种病毒，如乙肝病毒(HBV)和人类免疫缺陷病毒1型(HIV-1)。然而，APOBEC3蛋白(A3S)是否能使人乳头瘤病毒(HPV)DNA发生超突变，并在角质形成细胞中表现出抗病毒活性，目前尚不清楚。在这里，我们使用宫颈角质形成细胞W12细胞来研究A3S在HPV生命周期中的参与，W12细胞来自于低级别病变，并在其细胞核中保留了上体HPV16基因组。由于在整合的病毒DNA中经常发现作为边界序列的病毒E2基因，因此我们将其作为A3介导的超突变的潜在靶点。用β-干扰素处理W12细胞后，A3A、A3F和A3G等A3s的表达水平增加，并诱导E2基因的C-U转换，这种转换依赖于尿嘧啶DNA糖基酶的抑制。外源表达A3A和A3G也可诱导W12细胞发生E2过度突变。干扰素-β诱导的超突变可被针对A3G的小干扰RNA(适度地被针对A3A的干扰RNA)所阻断。然而，HPV16 Episome水平不受W12细胞A3A和A3G过表达的影响。本研究证实了干扰素-β上调的内源性A3s可诱导宫颈角质形成细胞中HPV16的E2超突变，并讨论了E2超突变的致病后果。
Apolipoprotein B mRNA-editing catalytic polypeptide 3 (APOBEC3) proteins are interferon (IFN)-inducible antiviral factors that counteract various viruses such as hepatitis B virus (HBV) and human immunodeficiency virus type 1 (HIV-1) by inducing cytidine (C)-to-uracil (U) mutations in viral DNA and inhibiting reverse transcription. However, whether APOBEC3 proteins (A3s) can hypermutate human papillomavirus (HPV) viral DNA and exhibit antiviral activity in human keratinocyte remains unknown. Here we examined the involvement of A3s in the HPV life cycle using cervical keratinocyte W12 cells, which are derived from low-grade lesions and retain episomal HPV16 genomes in their nuclei. We focused on the viral E2 gene as a potential target for A3-mediated hypermutation because this gene is frequently found as a boundary sequence in integrated viral DNA. Treatment of W12 cells with beta interferon (IFN-beta) increased expression levels of A3s such as A3A, A3F, and A3G and induced C-to-U conversions in the E2 gene in a manner depending on inhibition of uracil DNA glycosylase. Exogenous expression of A3A and A3G also induced E2 hypermutation in W12 cells. IFN-beta-induced hypermutation was blocked by transfection of small interfering RNAs against A3G (and modestly by those against A3A). However, the HPV16 episome level was not affected by overexpression of A3A and A3G in W12 cells. This study demonstrates that endogenous A3s upregulated by IFN-beta induce E2 hypermutation of HPV16 in cervical keratinocytes, and a pathogenic consequence of E2 hypermutation is discussed.