Miller A D
Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
Proc Natl Acad Sci U S A. 1996 Oct 15;93(21):11407-13. doi: 10.1073/pnas.93.21.11407.
Retroviruses can utilize a variety of cell-surface proteins for binding and entry into cells, and the cloning of several of these viral receptors has allowed refinement of models to explain retrovirus tropism. A single receptor appears to be necessary and sufficient for entry of many retroviruses, but exceptions to this simple model are accumulating. For example, HIV requires two proteins for cell entry, neither of which alone is sufficient; 10A1 murine leukemia virus can enter cells by using either of two distinct receptors; two retroviruses can use different receptors in some cells but use the same receptor for entry into other cells; and posttranslational protein modifications and secreted factors can dramatically influence virus entry. These findings greatly complicate the rules governing retrovirus tropism. The mechanism underlying retrovirus evolution to use many receptors for cell entry is not clear, although some evidence supports a mutational model for the evolution of new receptor specificities. Further study of factors that govern retrovirus entry into cells are important for achieving high-efficiency gene transduction to specific cells and for the design of retroviral vectors to target additional receptors for cell entry.
逆转录病毒可利用多种细胞表面蛋白进行结合并进入细胞，对其中几种病毒受体的克隆使得用于解释逆转录病毒嗜性的模型得以完善。对于许多逆转录病毒的进入而言，单一受体似乎是必要且充分的，但这种简单模型的例外情况正在不断增加。例如，HIV进入细胞需要两种蛋白，单独一种都不充分；10A1小鼠白血病病毒可通过两种不同受体中的任何一种进入细胞；两种逆转录病毒在某些细胞中可使用不同受体，但进入其他细胞时使用相同受体；翻译后蛋白质修饰和分泌因子可显著影响病毒进入。这些发现极大地使控制逆转录病毒嗜性的规则变得复杂。尽管一些证据支持新受体特异性进化的突变模型，但逆转录病毒进化为利用多种受体进入细胞的潜在机制尚不清楚。进一步研究控制逆转录病毒进入细胞的因素对于实现高效基因转导至特定细胞以及设计靶向其他细胞进入受体的逆转录病毒载体非常重要。
