美国洛克菲勒大学科学家在《自然》杂志上发表了一篇介绍新显微镜技术的 文章，这项技术能够只“照亮”细胞的表面。利用这一技术，科学家首次实 时、清晰地观察到了无数分子在活细胞中形成单个HIV粒子的过程。这一成果 将可能在开发艾滋病治疗方案方面提供帮助，并将改变艾滋病研究者的思考 方式。 这一新的技术称为全内反射显微镜方法（total internal reflection microscopy），与传统的显微镜照亮整个细胞不同，它仅仅照亮HIV聚集的细 胞表面。在这项技术的帮助下，能够非常详细地观察到细胞表面发生的情况 。利用这一技术，研究人员观察了HIV粒子装配的过程，并记录下了每个HIV 粒子装配所需的时间──5到6分钟。研究人员表示，这是首次观察到病毒粒 子诞生过程。并不仅仅限于HIV，可以是任何病毒。通过亲眼所见而不是推断 病毒粒子的装配过程，将提升我们思考问题的层次。这一技术的应用非常广 泛，它给了我们机会来回答那些之前无法回答的问题，不仅仅是病毒学方面 ，还包括一般的生物学方面。 Imaging the biogenesis of individual HIV-1 virions in live cells Observations of individual virions in live cells have led to the characterization of their attachment, entry and intracellular transport1. However, the assembly of individual virions has never been observed in real time. Insights into this process have come primarily from biochemical analyses of populations of virions or from microscopic studies of fixed infected cells. Thus, some assembly properties, such as kinetics and location, are either unknown or controversial2, 3, 4, 5. Here we describe quantitatively the genesis of individual virions in real time, from initiation of assembly to budding and release. We studied fluorescently tagged derivatives of Gag, the major structural component of HIV-1─which is sufficient to drive the assembly of virus-like particles6─with the use of fluorescence resonance energy transfer, fluorescence recovery after photobleaching and total-internal-reflection fluorescent microscopy in living cells. Virions appeared individually at the plasma membrane, their assembly rate accelerated as Gag protein accumulated in cells, and typically 5C6 min was required to complete the assembly of a single virion. These approaches allow a previously unobserved view of the genesis of individual virions and the determination of parameters of viral assembly that are inaccessible with conventional techniques. --

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