The protein syncytin, which is essential for formation of the placenta, originally came to the genome of our ancestors, and those of other mammals, via a retrovirus infection. Placental structures have also developed in non-mammalian vertebrates. The Mabuya lizard (pictured: image credit), which emerged 25 million years ago, has a placenta very much like those …
Retroviruses turned egg-layers into live-bearers Read More »
The influenza virus vaccine is frequently updated to ensure that it protects against infection with circulating virus strains. In some years the vaccine matches the circulating strains, but in others, there is a mismatch. The result is that the vaccine is less effective at protecting from infection. During the 2014-15 influenza season there was a …
When you are infected with a microbe, pieces of the pathogen are picked up by sentinel dendritic cells and brought to local lymph nodes. There the sentinels present their gifts to lymphocytes – B (pictured; image credit) and T cells – who then decide if they are foreign, in which case an immune response begins. …
Written with Amy Rosenfeld, Ph.D. By infecting organotypic brain slice cultures from embryonic mice, we have shown that Zika virus has always been neurotropic. The same culture system provides information on how Zika virus infection of the developing brain might lead to microcephaly.
Written with Amy Rosenfeld, Ph.D. Zika virus has been infecting humans since at least the 1950s (and probably earlier), but epidemics of infection have only been observed in the past ten years and congenital Zika syndrome in the last two. Two hypotheses emerged to explain this new pattern of disease: evolution of the virus, or …
What would happen to an RNA virus if its genome were placed in a bad neighborhood? The answer is that fitness plummets. RNA virus populations are not composed of a single defined nucleic acid sequence, but are dynamic distributions of many nonidentical but related members. In the past I have referred to these populations as quasispecies but …
