Okahara Goichi, Matsubara Shinobu, Oda Takaya, Sugimoto Jun, Jinno Yoshihiro, Kanaya Fuminori
Department of Molecular Biology, Ryukyu University School of Medicine, 207 Uehara, Okinawa 903-0215, Japan.
Genomics. 2004 Dec;84(6):982-90. doi: 10.1016/j.ygeno.2004.09.004.
The evolutional and biological roles of human endogenous retroviruses (HERVs) are less recognized compared to those of L1. In the present study, we focused on the transcriptional activity of HERVs in normal human tissues and found five HERV loci that are actively expressed in normal tissues. All but one showed tissue specificity of expression: one was expressed in stomach and small intestine and three were in placenta. We subsequently examined by TaqMan-based RT-PCR assays the temporal expression profiles of the three placenta-specific HERVs along with syncytin and syncytin 2 and observed three patterns. Syncytin and HERV-Fb showed almost constant expression through gestations. Syncytin 2 gradually decreased as pregnancy proceeded. In contrast, expression from the HERV-H/F and HERV-K(HML-6) loci increased remarkably in term placentas. Term placentas in general showed larger interindividual differences in HERV expression levels. Our results suggest that HERVs might have more diverse effects than currently thought.
与L1相比，人类内源性逆转录病毒（HERV）的进化和生物学作用鲜为人知。在本研究中，我们聚焦于HERV在正常人体组织中的转录活性，发现了五个在正常组织中活跃表达的HERV基因座。除一个外，其余均表现出表达的组织特异性：一个在胃和小肠中表达，三个在胎盘中表达。随后，我们通过基于TaqMan的RT-PCR分析检测了三个胎盘特异性HERV以及合胞素和合胞素2的时间表达谱，并观察到三种模式。合胞素和HERV-Fb在整个妊娠期表达几乎恒定。随着妊娠进展，合胞素2逐渐减少。相反，HERV-H/F和HERV-K（HML-6）基因座在足月胎盘中的表达显著增加。一般来说，足月胎盘在HERV表达水平上个体间差异较大。我们的结果表明，HERV可能具有比目前认为的更多样化的作用。
