NEWS OF THE WEEK
MEASLES SURPRISE IMAGING: Microscopy methods suggest a role for measles matrix protein in packaging viral RNA
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HE THREE-DIMENSIONAL organization of
PROC. NATL. ACA D. SCI . USA
measles virus appears to be different than what researchers had expected. The discovery of a protein-nucleic acid complex via electron microscopy studies could have implications for designing drugs that combat related viruses, such as respiratory syncytial virus or influenza. Many teams have mapped the measles virus layout in the past, but they used negative-stain electron microscopy, a technique that cannot peer inside the virus in its natural state. Sarah J. Butcher of the University of Helsinki, in Finland, and colleagues at Oxford University and Finland’s University of Turku, however, looked at measles virus with cryoelectron
NEW TWIST The measles matrix protein was thought to line part of the viral inner membrane (top). New data suggest it coats the helical nucleocapsid instead (bottom). Nucleocapsid = brown, matrix = blue, membrane = red, membrane glycoproteins = purple and yellow.
NATIONS BREAK IMPASSE ON WASTE
ORLD GOVERNMENTS have cleared the way to implement a long-pending ban of hazardous waste shipments from industrialized countries to developing nations. Countries agreed to the ban in 1995 under a United Nations treaty governing trade in waste known as the Basel Convention on the Control of Transboundary Movements of Hazardous Wastes & Their Disposal. But a diplomatic deadlock over an obscure procedural detail left the ban stuck in limbo for the past 16 years. It has not entered into force. At a weeklong meeting in Cartagena, Colombia, which ended on Oct. 21, governments came up with a plan for the ban to take effect. They agreed to a somewhat complicated formula: The ban will enter into force once 68 of the
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SHUTTERSTOCK
Under the Basel Convention, electronic waste, such as old computer equipment, can no longer be sent from developed nations to the developing world.
ENVIRONMENT: Ban to halt export of hazardous waste to developing world
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microscopy, which doesn’t have that limitation. The team detected a never-before-seen complex between the virus’s matrix protein (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.1105770108), thought to play a major part in viral assembly, and its nucleocapsid, which consists of viral RNA surrounded by protective capsid proteins. Until now, the scientific consensus was that the matrix protein covered the inner part of the viral membrane. The Finland team’s data suggest that the matrix protein instead coats sections of the helical nucleocapsid, packing it into bundles resembling rotini pasta. The existence of the added coating implies that additional steps are involved in virus replication, Butcher says. “And if you’ve got more steps, you’ve got more drug targets,” she adds. Though measles virus is largely controlled with vaccines in developed nations, her team is now studying related viruses to see whether they can detect similar helical complexes. The work “is very exciting as it seriously challenges the classical view of measles virus particle organization,” says Sonia Longhi, who studies measles virus protein structure at Aix-Marseille University and France’s National Center for Scientific Research (CNRS). “It will undoubtedly promote numerous future studies to unveil the determinants of coating and uncoating,” she adds.—CARMEN DRAHL VIDEO ONLINE
Peek inside measles virus at cenm.ag/measles.
90 countries that were parties to the Basel Convention in 1995 formally endorse the prohibition. According to the UN, 51 of these 90 countries have already ratified the ban. Thus, the ban will enter into force once 17 more take the same step. The Basel Action Network, an environmental group, predicts this will happen sometime in the next two to three years. The ban “ensures that developing countries are not convenient dumping grounds for toxic factory waste, obsolete ships containing asbestos, or old computers coming from affluent countries,” says Jim Puckett, executive directive of the Basel Action Network. Technically, the ban will prohibit shipment of hazardous waste from the 34 industrialized nations that are members of the Organization for Economic Cooperation & Development (OECD) to countries that are not members. OECD members include the U.S., Canada, European Union nations, Japan, and Mexico. The deal struck in Cartagena also sets the stage for new global talks on how developing countries that wish to accept hazardous waste imports can minimize health and environmental impacts of recycling and disposing of this material. Currently, 178 countries are parties to the Basel Convention. The U.S. signed and the Senate consented to ratify the Basel Convention. However, Congress has never passed legislation necessary for the U.S. to become an official party to the pact.—CHERYL HOGUE
OCTOBER 31, 2011
