During the earliest stages of a virus infection, cytokines are produced when innate immune defenses are activated. The rapid release of cytokines at the site of infection initiates new responses with far-reaching consequences that include inflammation. One of the earliest cytokines produced is tumor necrosis factor alpha (TNF-α), which is synthesized by activated monocytes and …
USA Today’s Snapshot for 29 June was a survey in which 1000 adults were asked to name a famous scientist. Here are the results: 47% named Albert Einstein 23% could not name anyone 6% named Marie Curie 4% named Louis Pasteur 4% named Thomas Edison The survey was conducted by L’Oreal, but the methods were …
Mutation is an important source of RNA virus diversity that is made possible by the error-prone nature of RNA synthesis. Viruses with segmented genomes, such as influenza virus, have another mechanism for generating diversity: reassortment. When an influenza virus infects a cell, the individual RNA segments enter the nucleus. There they are copied many times …
The RNA genome of influenza viruses is segmented . The virions of influenza A and B viruses contain 8 different RNAs, while those of influenza C viruses contain 7. How is the correct number of RNA segments inserted into newly synthesized virus particles? During influenza virus assembly, viral RNAs and viral proteins €“ called a …
The Centers for Disease Control and Prevention has published their weekly analysis of influenza activity for the week of 7-13 June 2009. They conclude that …influenza activity decreased in the United States, however, there were still higher levels of influenza-like illness than is normal for this time of year. During week 23, 38.7% of specimens …
The influenza virus hemagglutinin (HA) is the viral protein that attaches to cell receptors. The HA also plays an important role in the release of the viral RNA into the cell, by causing fusion of viral and cellular membranes. HA must be cleaved by cellular proteases to be active as a fusion protein. The HA …
Influenza HA cleavage is required for infectivity Read More »
