Researchers from the UCLA School of Dentistry investigating how stem cells can be used to regenerate dental tissue have discovered a way to produce cells with stem cell-like characteristics from the most common type of human skin cell in the epidermis.
Scientists in Canada have overcome a key research hurdle to developing regenerative treatments for diabetes and liver disease with a technique to produce medically useful amounts of endoderm cells from human pluripotent stem cells. The research, published in Biotechnology and Bioengineering, can be transferred to other areas of stem cell research helping scientists to navigate the route to clinical use known as the ‘valley of death’.
“One million people suffer from type 1 diabetes in the United States, while liver disease accounts for 45,000 deaths a year,” said Dr Mark Ungrin from the University of Toronto. “This makes stem cells, and the potential for regenerative treatments, hugely interesting to scientists. Laboratory techniques can produce thousands, or even millions, of these cells, but generating them in the numbers and quality needed for medicine has long been a challenge.”
The research focused on the process of using pluripotent stem cells (PSC) to generate endoderm cells, one of the three primary germ layers which form internal organs including the lungs, pancreas, and liver. The ability to differentiate, or transform, PSCs into endoderm cells is a vital step to developing regenerative treatments for these organs.
Studies of a protein that fruit flies use to sense heat and chemicals may someday provide solutions to human pain and the control of disease-spreading mosquitoes.
In the current issue of Nature, biologist Paul Garrity of the National Center for Behavioral Genomics at Brandeis University and his team, spearheaded by KyeongJin Kang and Vince Panzano in the Garrity lab, discover how fruit flies distinguish the warmth of a summer day from the pungency of wasabi by using TRPA1, a protein whose human relative is critical for pain and inflammation.
In earlier research Garrity’s team showed that flies, like humans, sense chemical irritants with TRPA1, indicating an ancient origin for harmful chemical sensing. In 2008, the team demonstrated that this protein serves a second function in flies: sensing warmth.
Gentle warmth and nasty chemicals trigger distinct responses. How can both responses rely on the same sensor? The team has now discovered that there is an easy answer. Insects actually make two forms of TRPA1, one specialized for each task.
Such TRPA1 specialization has implications for devising bug sprays and traps to combat the transmission of diseases like malaria, dengue and West Nile virus. “This work on TRPA1 can explain how blood-sucking insects like mosquitoes discriminate noxious chemicals, which repel them, from the warmth of a human, which attracts them,” says Garrity. “By activating one kind of TRPA1 you might be able to deter mosquitoes from biting you, while activating the other kind of TRPA1 might lure mosquitoes to a trap.”
These findings also have implications for understanding the way that human damage-sensing neurons work, explains Garrity. Since human TRPA1 is a drug target aimed at treating diseases such as asthma, migraines, and chronic pain, Garrity says it’s important to understand how TRPA1 proteins operate.
Food prices are soaring at the same time as Earth’s population is nearing 9 billion. As a result the need for increased crop yields is extremely important. New research led by Carnegie’s Wolf Frommer into the system by which sugars are moved throughout a plant — from the leaves to the harvested portions and elsewhere — could be crucial for addressing this problem. Their work is published December 8 by Science Express.
Just as it’s necessary for the human body to move nutrients to all of the organs, it is vital for green plants to transport sugars to supply its various parts. In humans, this is the circulatory system’s job. But plants do not have a heart-like pump to move these vital energy sources. Instead, plants use a molecular pump.
Twenty years ago, the Frommer team identified one of the key components of this molecular pump, which actively loads a sugar called sucrose into the plant’s veins, a tissue called phloem. But how the sucrose produced in the leaves via photosynthesis is delivered to the transporters that move it into the phloem has remained a mystery. Thus, a critical piece of the molecular pump was unknown—the protein that moves the sucrose to the inside of the plant’s leaf cell walls.
Frommer’s team included Carnegie’s Li-Qing Chen, the paper’s lead author, Xiao-Quing Qu, Bi-Huei Hou and Davide Sosso, as well as Sonia Osorio and Alisdair Fernie of the Max Planck Institute of Molecular Plant Physiology. In this new research they have identified the missing piece of the molecular pump system.