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Dengue structure differs at the temperatures of its human and mosquito hosts.

ABSTRACT: We report on a conformational transition of dengue virus when changing the temperature from that present in its mosquito vectors to that of its human host. Using cryoelectron microscopy, we show that although the virus has a smooth surface, a diameter of ?500 Å, and little exposed membrane at room temperature, the virions have a bumpy appearance with a diameter of ?550 Å and some exposed membrane at 37 °C. The bumpy structure at 37 °C was found to be similar to the previously predicted structure of an intermediate between the smooth mature and fusogenic forms. As humans have a body temperature of 37 °C, the bumpy form of the virus would be the form present in humans. Thus, optimal dengue virus vaccines should induce antibodies that preferentially recognize epitopes exposed on the bumpy form of the virus.

SUBMITTER: Zhang X

PROVIDER: S-EPMC3637732 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Dengue structure differs at the temperatures of its human and mosquito hosts.

Zhang Xinzheng X Sheng Ju J Plevka Pavel P Kuhn Richard J RJ Diamond Michael S MS Rossmann Michael G MG

Proceedings of the National Academy of Sciences of the United States of America 20130408 17

We report on a conformational transition of dengue virus when changing the temperature from that present in its mosquito vectors to that of its human host. Using cryoelectron microscopy, we show that although the virus has a smooth surface, a diameter of ∼500 Å, and little exposed membrane at room temperature, the virions have a bumpy appearance with a diameter of ∼550 Å and some exposed membrane at 37 °C. The bumpy structure at 37 °C was found to be similar to the previously predicted structure ...[more]

PMID: 23569243

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Dataset Information

Dengue structure differs at the temperatures of its human and mosquito hosts.

Publications

Dengue structure differs at the temperatures of its human and mosquito hosts.

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