Seminar by Yukihiko Sugita, DVM Institute of Medical Science, University of Tokyo

Dear All,

Molecular Cryo-Electron Microscopy Unit (Wolf Unit) would like to invite you to a Seminar by Dr. Yukihiko Sugita, from Institute of Medical Science, University of Tokyo

Speaker:    Yukihiko Sugita, DVM

                   Institute of Medical Science, University of Tokyo

Title: Morphogenesis of Influenza Virus Particle

Abstract:

Influenza A virus, a member of the Orthomyxoviridae, is an enveloped virus with an eight-segmented, negative-sense, single-stranded RNA genome. When influenza virions are observed by using negative-staining electron microscopy, they often appear as spherical, elliptical, filamentous, or sometimes irregular shapes, which is referred to as pleomorphism. Inside the virion, each viral genomic RNA segment forms a ribonucleoprotein complex (RNP) together with viral nucleoproteins and the heterotrimeric RNA-dependent RNA polymerase complex. Recent electron microscopic studies have shown that eight RNPs are arranged in a specific array, with seven RNPs surrounding a central one, and are selectively packaged into the virion, underneath its budding tip. Extensive research on the polymorphic outer features of the virions and on the RNP architecture inside the virions has been conducted; however, the morphogenesis of influenza virions is not yet fully understood.

          By using various electron microscopic techniques, I have studied the interior and exterior morphologies of influenza virions. In the first part, to clarify the native morphology of the influenza virion, I attempted to determine whether the irregular-shaped influenza virion is native and which viral component is important for virion integrity. In the second part, I analyzed the orientation of the viral RNPs inside the virion to elucidate the morphogenesis and genome packaging mechanisms of influenza virus.

We hope to see many of you at the Seminar.

Best Regards,

Rika Yoshizawa

Research Administrator

Molecular Cryo-Electron Microscopy Unit (Wolf Unit)