Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Virology. 2011 Sep 1;417(2):334-42. doi: 10.1016/j.virol.2011.06.017. Epub 2011 Jul 12.
The F16L gene of vaccinia virus (VACV) is conserved in all chordopoxviruses except avipoxviruses. The crocodile poxvirus F16 protein ortholog has highly significant similarity to prokaryotic serine recombinases and contains all amino acids that comprise the catalytic site. In contrast, F16 orthologs encoded by other poxviruses show only marginally significant similarity to serine recombinases, lack essential amino acids of the active site and are most likely inactive derivatives of serine recombinases. Nevertheless, the conservation of F16L in non-avian poxviruses suggested an important function. However, a VACV mutant with the F16L gene knocked out replicated normally in dividing and quiescent cells. The F16 protein was synthesized early after infection and detected in virus cores. When expressed in infected or uninfected cells, F16 accumulated in nucleoli depending on the level of expression and confluency of cells. Evidence was obtained that F16 forms multimers, which might regulate concentration-dependent intracellular localization.
痘病毒 F16L 基因在所有正痘病毒中都保守，除了禽痘病毒。鳄鱼类痘病毒 F16 蛋白的直向同源物与原核丝氨酸重组酶高度相似，并且包含组成催化位点的所有氨基酸。相比之下，其他痘病毒编码的 F16 直向同源物与丝氨酸重组酶只有轻微的相似性，缺乏活性位点的必需氨基酸，很可能是丝氨酸重组酶的非活性衍生物。尽管如此，F16L 在非禽类痘病毒中的保守性表明它具有重要的功能。然而，F16L 基因敲除的 VACV 突变体在分裂和静止细胞中正常复制。F16 蛋白在感染后早期合成，并在病毒核心中检测到。当在感染或未感染的细胞中表达时，F16 根据表达水平和细胞的汇合程度积累在核仁中。有证据表明 F16 形成多聚体，这可能调节浓度依赖性的细胞内定位。
