TWiV 226: Taking the viral A train with Terry Dermody

On episode #226 of the science show This Week in Virology, Vincent and Dickson speak with Terry Dermody about his career in medicine and virology.

You can find TWiV #226 at www.microbe.tv/twiv.

Aaron J. Shatkin, 77

Aaron J ShatkinAaron J. Shatkin was well known for his work on reoviruses beginning in the 1960s in his laboratory at the Roche Institute of Molecular Biology in Nutley, NJ and then at Rutgers University. He was among the first to appreciate that virus particles contained many different enzymes, such as RNA polymerase and poly(A) polymerase, that could be readily purified and used to study aspects of the viral replication cycle. His studies of reovirus mRNAs revealed an unusual methylated, blocked 5′-terminal structure, m-7G(5′)ppp(5′)G-MpCp-. He found that the 5′-terminal G of reovirus mRNAs made in purified virions or in infected cells was linked to the second G via a 5′-5′ chemical linkage, not the typical 5′-3′ linkage found in nucleic acids. This structure, soon to be called the cap, was subsequently found on many other viral and cellular mRNAs. His laboratory found that the cap is required for efficient translation of mRNA and also for mRNA stability. His discovery of a protein that binds the cap, now called eIF4E, lead to our understanding of how ribosomes are recruited to mRNAs to initiate protein synthesis. In recent years he became interested in the enzymatic machinery in cells that is responsible for synthesis of the cap structure, the capping enzyme. He studied the role of the capping enzyme in the nematode C. elegans and, in one of his last papers, solved the structure of the protein.

I have very good memories of Aaron: in 1979 I interviewed for a postdoctoral position in his laboratory at the Roche Institute (during my seminar I also met Ann Skalka with whom I co-authored a virology textbook many years later). Aaron was the first to offer me a postdoctoral position. I recall him being extremely kind and genuinely interested in my career. When I told him I was also interested in David Baltimore’s laboratory, he quipped ‘You’ll be lucky to even talk to him’; but he had a smile on his face. I was lucky to obtain a position in the Baltimore lab, and when I called Aaron to tell him, he was extremely gracious and congratulatory.

Over the years I met Aaron on many occasions; he was always friendly and cheerful and we often had long scientific conversations. When I moved to Scotch Plains, NJ in 1989 I was surprised to find that Aaron lived just around the corner, less than a mile away. I often saw him jogging by my home on Saturday mornings. Once I pointed him out to my older son: ‘that is the man who discovered the cap on mRNAs!’ My son had just studied the mRNA cap in high school biology so he knew what I meant. After that he often told his friends that the cap-discoverer lived near him in NJ.

Cooper Island rally

Several years ago, when our town wanted to build a home on a nearby small island of land, residents organized a rally to protest the development. It was called ‘Save Cooper Road Island‘ and Aaron and his wife Joan came to lend their support! You can see me with Aaron in photographs of the event (In the photo at left, he is to my left, wearing khaki pants, a dark jacket, and white cap; I am holding a sign, and Joan is to my right).

Just over a year ago he interrupted one of his runs to come by and tell me that his wife had passed away. ‘It’s a bummer’, he said, ‘I have to do all the cooking and cleaning by myself’. I asked him when he was going to retire, and he said now that his wife had died, he would probably keep working as long as he lived. Which he did.

Aaron was a terrific person and scientist. I will miss watching him jog by, telling people that my neighbor discovered the mRNA cap, and thinking about him as I drive past his home. I had planned for years to organize a dinner with him and my Ph.D. mentor, Peter Palese (Peter did a postdoctoral fellowship at the Roche Institute while Aaron was there and knew him well). I also planned to interview Aaron for TWiV. Now I can’t do either. I really should learn not to put off doing important things.

Related:

On the Death of Aaron J. Shatkin

Aaron J. Shatkin Ph.D. Obituary

Photos from a presentation (pdf)

TWiV 131: A REOstat for cancer

reovirus coreHosts: Vincent Racaniello, Alan Dove, Dickson Despommier, and Brad Thompson

Vincent, Alan, and Dickson chat with Brad Thompson, CEO of Oncolytics Biotech, about using reovirus to treat cancer.

Click the arrow above to play, or right-click to download TWiV #131 (42 MB .mp3, 97 minutes).

Subscribe to TWiV (free) in iTunes , at the Zune Marketplace, by the RSS feed, by email, or listen on your mobile device with the Microbeworld app.

Links for this episode:

Weekly Science Picks

Dickson – Angels and Insects
Alan – Science Buddies
Vincent – Emerging Diseases: The Importance of Early Warning and Surveillance (YouTube)

Listener Pick of the Week

Josh  – Prof. Racaniello’s Virology course on iTunes

Send your virology questions and comments (email or mp3 file) to twiv@microbe.tv, or call them in to 908-312-0760. You can also post articles that you would like us to discuss at microbeworld.org and tag them with twiv.

Reovirus infection of farmed salmon

Global fish farming may be the solution to the impending collapse of the commercial fishing industry, but penned fish are susceptible to infectious diseases. Infection with salmon infectious anemia virus, an orthomyxovirus, lead Wal-Mart to stop buying farmed salmon from Chile, the world’s second largest producer of the fish. As a consequence Chilean farmed salmon are being immunized to prevent infection. Heart and skeletal muscle inflammation (HSMI) is another disease of farmed salmon, first detected in Norway – the world’s largest supplier of the fish – in 1999. The results of deep sequencing suggest that HSMI is caused by a novel piscine reovirus.

HSMI was transmitted to salmon by inoculation with tissue extracts of diseased fish or by co-habitation. RNA was extracted from the heart and subjected to high throughput sequence analysis, which revealed the presence of a novel member of the reovirus family. These are are non-enveloped, icosahedral viruses with 10-12 segments of double-stranded RNA that infect a variety of hosts, including humans: rotaviruses are important agents of gastroenteritis.

The presence of piscine reovirus in salmon with HSMI was examined by polymerase chain reaction assays. Included were heart and kidney samples from 29 salmon from three different outbreaks of HSMI, and from 10 healthy fish. All but one of the diseased fish, and none of the healthy fish, contained PRV nucleic acid. To determine the prevalence of PRV in healthy salmon, samples were collected from 9 different Norwegian coastal waters. Sixteen of 66 (24.2%) of these fish were positive for PRV.

Is heart and skeletal muscle inflammation of salmon caused by piscine reovirus? It’s possible, but further work is needed to prove causality, as the authors write:

Formal implication of PRV in HSMI will require isolation in cell culture and fulfillment of Koch’s postulates, or prevention or modification of disease through use of specific drugs or vaccines.

It’s important to identify the etiologic agent of HSMI because it is a threat to both farmed and wild salmon. Farmed fish are kept in pens in the open ocean, facilitating spread of infectious diseases to wild fish. Knowledge of the causative agent will permit preventive measures such as immunization.

Palacios G, Lovoll M, Tengs T, Hornig M, Hutchison S, Hui J, Kongtorp RT, Savji N, Bussetti AV, Solovyov A, Kristoffersen AB, Celone C, Street C, Trifonov V, Hirschberg DL, Rabadan R, Egholm M, Rimstad E, & Lipkin WI (2010). Heart and skeletal muscle inflammation of farmed salmon is associated with infection with a novel reovirus. PloS one, 5 (7) PMID: 20634888

TWiV 89: Where do viruses vacation?

Hosts: Vincent Racaniello and Alan Dove

On episode #89 of the podcast This Week in Virology, Vincent and Alan review recent findings on the association of the retrovirus XMRV with ME/CFS, reassortment of 2009 pandemic H1N1 influenza virus in swine, and where influenza viruses travel in the off-season.

Click the arrow above to play, or right-click to download TWiV #89 (56 MB .mp3, 78 minutes)

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Links for this episode:

Weekly Science Picks

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Send your virology questions and comments (email or mp3 file) to twiv@microbe.tv or leave voicemail at Skype: twivpodcast. You can also post articles that you would like us to discuss at microbeworld.org and tag them with twiv.

Virology lecture #6: RNA-directed RNA synthesis


Download: .wmv (324 MB) | .mp4 (76 MB)

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