"Sheep's blood or cow's blood," said Clem, an associate professor of biology at Kansas State University. "This particular species is less finicky than others," so Clem won't need to stock their cages with sweaty socks. (Some mosquitoes won't feed without the persuasive scent of humans in the air.)
Clem, who studies molecular virology, is going out of his way to accommodate A. aegypti in hopes of learning more about how viruses disrupt the programmed death of cells, or apoptosis.
"Millions of cells are dying at any given moment in our body," Clem said. "And that's a good thing."
Programmed cell death is tidier than necrosis, in which injury prompts inflammatory cells to rush in and clean up. In contrast, apoptosis relies on a cell's genes to trigger an orderly disassembly.
It's the body's way of removing tissue that has done its job, such as the webbing between the developing fingers of an embryo, or cells whose DNA is damaged. Malfunctions in apoptosis are associated with cancer, neurological diseases such as Alzheimer's and immune disorders such as AIDS and rheumatoid arthritis.
Though scientists knew of apoptosis as long ago as the late 1800s, interest in the field has intensified only in the last 15 years, Clem said.
"It was very obscure" when he was a graduate student at the University of Georgia in the early 1990s, he said. "Now it's taught to undergraduates."
Clem's current experiment, helped by a grant from the National Institutes of Health, grew from his work with moths that were naturally immune to fatal viruses. Clem chose A. aegypti for this round because it spreads such diseases as dengue fever, the most important of the world's mosquito-borne viruses. The Centers for Disease Control estimate that 100 million cases occur annually.
But the mosquito's effectiveness in spreading the disease varies from place to place. Clem wants to find out whether apoptosis plays a role in that variability.
Once his mosquitoes are safely housed in their lab, Clem plans to infect them with genetically altered strains of Sindbis, a virus related to those that cause equine encephalitis. Some strains will contain genes that block apoptosis, Clem said, and others will encourage the process.
He will go on to test other mosquitoes with unaltered strains of Sindbis. The results should suggest whether A. aegypti can be made immune to viruses.
Clem stresses that A. aegypti's living arrangements will be anything but casual. His lab's insectary is approved by the CDC to conform to "arthropod containment level 2," which specifies such things as screened drainage, extensive caulking, and heat-sterilization of equipment and waste. So whatever you're swatting this summer, it won't be one of Clem's mosquitoes.
"Our work will be taking place in a very secure environment," he said.
In the Western Hemisphere, A. aegypti is widespread in Latin America but occupies only bits of the southern United States, particularly south Florida. The species has made a comeback since eradication programs ended in the 1970s, and dengue fever has expanded along with it.
In Kansas, Culex tarsalis and other members of the Culex group do most of the biting. They don't transmit dengue, but C. tarsalis is known to spread West Nile and western equine encephalitis. The world's most troublesome mosquito-borne disease, malaria, is spread by Anopheles gambiae.
One of Clem's students is investigating a dozen or so genes in A. aegypti because of their similarity to genes that control apoptosis in the fruit fly. "But even in humans, the genes are similar in their sequence," Clem said. This phenomenon of "gene homology" means that insects have a lot to tell the species on the other end of the microscope about its own genetic workings.
Rollie Clem | EurekAlert!
Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel
Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Business and Finance
22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy