Al-Homsi A S, Berger C, van Baarle D, Kersten M J, Klein M R, McQuain C, van Oers R, Knecht H
LINK Laboratories, Cancer Center, University of Massachusetts Medical Center, Worcester, MA 01655, USA.
Int J Mol Med. 1998 Jun;1(6):983-7. doi: 10.3892/ijmm.1.6.983.
EBNA-2 is the first protein to be detected after infection of primary B lymphocytes by Epstein-Barr virus (EBV) and plays an essential role as transcriptional activator in EBV-induced lymphocyte transformation. We analysed by PCR and sequencing regions of the EBNA-2 type 1 gene from isolates from 13 children with infectious mononucleosis (IM), 6 children with tonsillar hyperplasia (TH), and 9 patients with HIV infection followed longitudinally. We found in all three groups of patients frequent non-silent point mutations at positions 48990, 48991, 49021, 49057, 49083, 49089, 49091, 49113, 49119, 49140, 49156, and a triplet insertion at position 49136. While 4 out of 13 samples from patients with IM showed a mosaic pattern suggesting co-existence of more than 1 substrain of EBNA-2 type 1, none of the samples from TH showed this pattern consistent with substrain selection during clinical latency. No sequence changes were noted over time in samples derived from patients with HIV infection. We conclude that in analogy to the coexistence of several subtypes of EBNA-1 in healthy EBV carriers, samples from IM can harbor more than one subtype of the EBNA-2 type 1 gene.
EBNA-2是爱泼斯坦-巴尔病毒（EBV）感染原发性B淋巴细胞后最早被检测到的蛋白质，在EBV诱导的淋巴细胞转化中作为转录激活因子发挥重要作用。我们通过聚合酶链反应（PCR）和测序分析了13例传染性单核细胞增多症（IM）患儿、6例扁桃体增生（TH）患儿以及9例接受纵向随访的HIV感染患者的EBNA-2 1型基因分离株区域。我们在所有三组患者中均发现，在48990、48991、49021、49057、49083、49089、49091、49113、49119、49140、49156位点存在频繁的非同义点突变，以及在49136位点有一个三联体插入。虽然13例IM患者样本中有4例呈现嵌合模式，提示EBNA-2 1型存在不止1个亚株共存，但TH患者的样本均未呈现这种模式，这与临床潜伏期的亚株选择一致。HIV感染患者的样本随时间未观察到序列变化。我们得出结论，类似于健康EBV携带者中EBNA-1的几种亚型共存，IM患者的样本可携带不止一种EBNA-2 1型基因亚型。
