Plant Molecular Farming

While healthy people have proteins in their blood called clotting factors that act quickly to plug wounds, hemophiliacs lack these proteins, making even minor bleeds difficult to stop.

The main treatment option for people with severe hemophilia is to receive regular infusions of clotting factor. But 20 to 30 percent of people who get these infusions develop antibodies, called inhibitors, against the clotting factor. Once these inhibitors develop, it can be very difficult to treat or prevent future bleeding episodes.

In a new study, researchers from the University of Pennsylvania School of Dental Medicine and theUniversity of Florida College of Medicine teamed up to develop a strategy to prevent these antibodies from forming. Their approach, which uses plant cells to teach the immune system to tolerate rather than attack the clotting factor protein, offers hope for preventing one of the most serious complications of hemophilia treatment.

Will the public swallow science’s best solution to one of the most dangerous wheat pathogens on the planet?

Some wheat varieties are resistant to Ug99, but they represent just 10 percent of the varieties grown around the world. And even these plants are not necessarily immune to infection. Ug99 continues to mutate and spread, and new virulent races, or biotypes, of the fungus that are able to skirt plant resistance strategies could emerge at any time. Just last year, for example, outbreaks of a novel stem rust race in Ethiopia and Germany infected Ug99-resistant wheat plants. In the oft-repeated words of the late wheat-breeding pioneer Norman Borlaug of the Rockefeller Foundation and CIMMYT, “Rust never sleeps.”

Most wheat researchers and breeders agree that to protect plants from Ug99, they must develop wheat varieties with several rust-resistance genes, so that if the fungus mutates to outwit one defense, there are others there to take on the pathogen. The problem is that it can take years to achieve this goal using traditional breeding methods. In the meantime, favorable winds could spread Ug99 even farther, and the fungus continues to evolve resistance to wheat crops’ natural defenses.

One way to hasten the development of a long-lasting stem rust–resistant wheat variety is to engineer plants’ DNA to carry resistance genes, creating what are known as genetically modified (GM) crops. But at many of the facilities that develop wheat varieties—primarily led by academic breeding groups, in contrast to the commercial domination of corn and soybean development—such transgenic approaches are taboo, as public opposition, regulatory expenses, and genetic complexity have kept wheat transgenics off the market. “We could do millions of things [with transgenics],” says Jorge Dubcovsky, a wheat geneticist and breeder at the University of California, Davis, “but we have our hands tied.”

All 18 monkeys exposed to a lethal dose of the virus and given the experimental drug survived, raising hopes that ZMapp will work in people.

Giving ZMapp, a cocktail of antibodies, to rhesus macaques up to five days after infection with the Ebola virus completely protected the animals — a finding that a Canadian-led research team says supports use of the treatment during the current outbreak in West Africa.

Kathy Willis examines how we are building future resilience into our modern crops.

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The body is structured to ensure that any invading organisms have a tough time reaching the brain, an organ obviously critical to survival. Known as the blood-brain barrier, cells that line the brain and spinal cord are tightly packed, making it difficult for anything besides very small molecules to cross from the bloodstream into the central nervous system. While beneficial, this blockade also stands in the way of delivering drugs intended to treat neurological disorders, such as Alzheimer’s.

In a new study published in the journal Molecular Therapy, University of Pennsylvania researchers have found a way of traversing the blood-brain barrier, as well as a similar physiological obstacle in the eye, the retinal-blood barrier. By pairing a receptor that targets neurons with a molecule that degrades the main component of Alzheimer’s plaques, the biologists were able to substantially dissolve these plaques in mice brains and human brain tissue, offering a potential mechanism for treating the debilitating disease, as well as other conditions that involve either the brain or the eyes.

The recent finding of the tryptophan aminotransferase (TAA)/flavin monooxygenase (YUC) pathway as the principal route of auxin production in plants provides an opportunity to revisit the origin of plant auxin biosynthesis. Phylogenetic analyses of the TAA and YUC gene families provide very little evidence for the production of indole-3-acetic acid (IAA) in algae. Instead, horizontal gene transfer of YUCs from bacteria to the ancestral land plant suggests that the TAA/YUC pathway is a land plant innovation. In this Opinion article we postulate that the origin of tryptophan-dependent IAA biosynthesis in land plants might have evolved in response to interactions with microbes, particularly bacteria, allowing plants to counteract bacterial activities and control their own auxin signaling.

A Liberian health worker who recovered from Ebola after receiving an experimental drug is urging the manufacturer to speed up its production and send it to Africa,

Two Ebola patients, given the experimental drug ZMapp, have been allowed to leave a treatment centre in the Liberian capital after testing negative for the disease. The pair – both medics – were greeted by country’s president in Monrovia.

“Really, really good news. First of all I just want to say to both of you, how happy we are that you have survived this,” said Ellen Johnson Sirleaf.

Meanwhile, residents have been celebrating the lifting of a blockade in a neighbourhood of the capital.

Streets in the West Point district had been closed for 10 days after an Ebola health centre was stormed.

Residents had feared that they would run out of food and safe water due to the outbreak.

In Sierra Leone, youth groups have taken to the streets of Freetown to raise awareness of Ebola, as the virus continues to spread.

More than three thousand cases have now been reported across West Africa.

Liberia has been the hardest hit, reporting at least 694 deaths.

Senegal has joined the list of affected countries, announcing its first case on Friday.