Onafuwa-Nuga Adewunmi A, Telesnitsky Alice, King Steven R
RNA. 2006 Apr;12(4):542-6. doi: 10.1261/rna.2306306. Epub 2006 Feb 17.
The virion incorporation of 7SL, the RNA component of the host signal recognition particle (SRP), has been shown for several simple retroviruses. Data here demonstrate that 7SL is also packaged by HIV-1, in sevenfold molar excess of genomic RNA. Viral determinants of HIV-1 genome and primer tRNA packaging were not required for 7SL incorporation, as virus-like particles with only minimal assembly components efficiently packaged 7SL. The majority of 7SL within cells resides in ribonucleoprotein complexes bound by SRP proteins, and most SRP protein exists in signal recognition particles. However, Western blot comparison of virion and cell samples revealed that there is at least 25-fold less SRP p54 protein per 7SL RNA in HIV-1 particles than in cells. Comparing 7SL:actin mRNA ratios in virions and cells revealed that 7SL RNA appears selectively enriched in virions.
几种简单逆转录病毒已被证明其病毒粒子中含有宿主信号识别颗粒（SRP）的RNA成分7SL。此处数据表明，HIV-1也会包装7SL，其摩尔数是基因组RNA的七倍。HIV-1基因组和引物tRNA包装的病毒决定因素并非7SL掺入所必需，因为仅具有最小组装成分的病毒样颗粒就能有效地包装7SL。细胞内的大多数7SL存在于与SRP蛋白结合的核糖核蛋白复合物中，并且大多数SRP蛋白存在于信号识别颗粒中。然而，病毒粒子和细胞样本的蛋白质免疫印迹比较显示，HIV-1颗粒中每7SL RNA所含的SRP p54蛋白比细胞中至少少25倍。比较病毒粒子和细胞中7SL与肌动蛋白mRNA的比率发现，7SL RNA在病毒粒子中似乎有选择性地富集。
