Archive for June, 2012

The subgenomic promoter of brome mosaic virus folds into a stem–loop structure capped by a pseudo-triloop that is structurally similar to the triloop of the genomic promoter

23 June, 2012

See on Scoop.itVirology News

In brome mosaic virus, both the replication of the genomic (+)-RNA strands and the transcription of the subgenomic RNA are carried out by the viral replicase. The production of (−)-RNA strands is dependent on the formation of an AUA triloop in the stem–loop C (SLC) hairpin in the 3′-untranslated region of the (+)-RNA strands. Two alternate hypotheses have been put forward for the mechanism of subgenomic RNA transcription. One posits that transcription commences by recognition of at least four key nucleotides in the subgenomic promoter by the replicase. The other posits that subgenomic transcription starts by binding of the replicase to a hairpin formed by the subgenomic promoter that resembles the minus strand promoter hairpin SLC. In this study, we have determined the three-dimensional structure of the subgenomic promoter hairpin using NMR spectroscopy. The data show that the hairpin is stable at 30°C and that it forms a pseudo-triloop structure with a transloop base pair and a nucleotide completely excluded from the helix. The transloop base pair is capped by an AUA triloop that possesses an extremely well packed structure very similar to that of the AUA triloop of SLC, including the formation of a so-called clamped-adenine motif. The similarities of the NMR structures of the hairpins required for genomic RNA and subgenomic RNA synthesis show that the replicase recognizes structure rather than sequence-specific motifs in both promoters.

See on rnajournal.cshlp.org

Trade Secrets: Are Green Vaccines Appropriate for Africa? : Trade Secrets

21 June, 2012

See on Scoop.itVirology News

I have mentioned several times here, and elsewhere, that my lab works on expressing vaccine-relevant viral proteins in plants – and that I think this is a highly appropriate technology for the purpose.  Read more…

See on blogs.nature.com

Dengue vaccine results from Thailand trial expected by September | The Jakarta Post

16 June, 2012

See on Scoop.itVirology News

The efficacy of the first dengue fever vaccine is expected to be known by September when results of tests on thousands of Thai children will be …

See on www.thejakartapost.com

GM Crops Offer Natural Pest Control | The Scientist

14 June, 2012

See on Scoop.itVirology News

“They found that across all sites as insecticide spraying declined, predatory arthropod populations rose, bringing down populations of aphids, insects that consume and damage crops by carrying viruses . In addition, the team also studied experimental Bt cotton plots, and found that where predator populations were high in the Bt cotton, they were correspondingly high in surrounding peanut and soybean plots, suggesting the benefits of increased predators spilled over to neighboring crops.”

 

In.  Your.  FACES!!  Loony.  Greenies.  Actual proven BENEFITS!!  From GM!!  From a long term, HUGE experiment!!  I’ve been waiting a while for this.

See on the-scientist.com

Canadian researchers thwart Ebola virus

14 June, 2012

See on Scoop.itVirology News

Cure has the longest treatment window so far resulting in full recovery – a full day…The treatment, in which injections of protein-grabbing antibodies stop a virus from replicating, has the longest treatment window so far resulting in full recovery – a full day. There’s just one catch: It can take up to two weeks for symptoms of the disease to appear.

In an article published Wednesday in Science and Translational Medicine, Gary Kobinger and several others outline the cocktail of antibodies they used to treat macaque monkeys infected with the most lethal strain of Ebola virus. All the macaques treated 24 hours after infection recovered, as did half of those treated after 48 hours.

I must learn how to do science via press release – looks like you get much more interest that way….
See on www.theglobeandmail.com

Single science council proposed for South Africa

12 June, 2012

See on Scoop.itVirology News

“A committee has advised South Africa’s government to set up a national council to steer the country’s research agenda and make recommendations on all major funding allocations to science and innovation.

The 15 to 20 member council would be chaired by the country’s deputy president and the science minister would be deputy chair, to ensure legitimacy across all government departments.

The council would include other ministers as well as representatives from academia and industry, says the committee’s report, published for public consultation on 6 May by the Department of Science and Technology.”

While a good idea in principle, this could work out just like SA’s last effort at consolidating funding bodies: the creation of the Technology and Innovation Agency resulted in the abrupt cessation of funding from the bodies it replaced, with only a trickle starting to become available now.

See on www.research-africa.net

Province on rabies alert | The New Age Online

12 June, 2012

See on Scoop.itVirology News

“A three-year-old boy from Umlazi [KwaZulu-Natal, SA] was close to becoming the fourth victim of rabies in the province following an outbreak of the disease that has killed three people in the past month.

The toddler has been at the Prince Mshiyeni Memorial Hospital for the past two weeks and, according to the department of environmental affairs, is showing signs of recovery.

“We have been in contact with his mother since he was admitted to hospital and she says there are improvements. He can now sit and has started swallowing liquids. He also responds when she calls his name but he still cannot speak properly,” said department spokesperson Jeffrey Zikhali.”

 

If that’s the case, then it’s close to being a miracle.  The problem appears to be lack of general immunisation of domestic animals, and a lack of government-supplied vaccine for free distribution.

See on www.thenewage.co.za

Virus poses added threat to isle honey bees – Hawaii News – Honolulu Star-Advertiser

11 June, 2012

See on Scoop.itVirology News

The varroa mite is causing a highly contagious virus to proliferate in honeybee colonies here and around the globe, Hawaii and British researchers have found.

Researchers from the University of Hawaii, the University of Sheffield in South Yorkshire, the British Marine Biological Association, and the British Food and Environmental Research Agency studied the pest in Hawaii.

Their research, reported Friday in the journal Science, showed how the varroa mite caused the virus, a known pathogen, to increase its frequency among honeybee colonies to 100 percent from 10 percent.

The study showed that along with this change, a millionfold increase in the number of virus particles infect- ing each bee and a huge reduction in viral strain diversity led to the single virulent virus that deforms wings.

See on www.staradvertiser.com

Vaccine gets credit for decline in sex infection [in New Zealand]

11 June, 2012

See on Scoop.itVirology News

“A nationwide drop in the number of genital warts cases has been attributed to the controversial HPV vaccine, which is free for teenage girls.

Sexual health clinics reported a 10 per cent decrease in genital warts last year compared to 2010, according to the Institute of Environmental Science and Research’s annual report on sexually transmitted infections.

Family Planning national medical advisor Christine Roke attributed the fewer first-time cases of genital warts to the HPV vaccine, which was introduced in late 2008.

“It reduces the chances of getting warts if people have it before they are sexually active.”

The vaccine – now a routine immunisation for 12-year-old girls – aims to protect women against human papillomavirus and the risk of developing cervical cancer later in life.”

 

Nice example of the knock-on effect in public health due to a vaccine – in this case, even though only girls are getting the papillomavirus vaccine, bot sexes are protected against spread of genital warts caused by the viruses.

 

HPV graphic courtesy of Russell Kightley Media

See on www.stuff.co.nz

PLoS Pathogens: Mobilization of HIV Spread by Diaphanous 2 Dependent Filopodia in Infected Dendritic Cells

8 June, 2012

See on Scoop.itVirology and Bioinformatics from Virology.ca

“Paramount to the success of persistent viral infection is the ability of viruses to navigate hostile environments en route to future targets. In response to such obstacles, many viruses have developed the ability of establishing actin rich-membrane bridges to aid in future infections. Herein through dynamic imaging of HIV infected dendritic cells, we have observed how viral high-jacking of the actin/membrane network facilitates one of the most efficient forms of HIV spread. Within infected DC, viral egress is coupled to viral filopodia formation, with more than 90% of filopodia bearing immature HIV on their tips at extensions of 10 to 20 µm. Live imaging showed HIV filopodia routinely pivoting at their base, and projecting HIV virions at µm.sec−1 along repetitive arc trajectories. HIV filopodial dynamics lead to up to 800 DC to CD4 T cell contacts per hour, with selection of T cells culminating in multiple filopodia tethering and converging to envelope the CD4 T-cell membrane with budding HIV particles. Long viral filopodial formation was dependent on the formin diaphanous 2 (Diaph2), and not a dominant Arp2/3 filopodial pathway often associated with pathogenic actin polymerization. Manipulation of HIV Nef reduced HIV transfer 25-fold by reducing viral filopodia frequency, supporting the potency of DC HIV transfer was dependent on viral filopodia abundance. Thus our observations show HIV corrupts DC to CD4 T cell interactions by physically embedding at the leading edge contacts of long DC filopodial networks.”

 

A really nice microscopy paper, backed up by some good good molbiol, revealing another way virus – and in this case HIV – can hijack natural interactions of cells of the immune system to further its own spread.

See on www.plospathogens.org