Tag Archives: research

Mapping the embryonic epigenome: How genes are turned on and off during early human development

After an egg has been fertilized, it divides repeatedly to give rise to every cell in the human body — from the patrolling immune cell to the pulsing neuron. Each functionally distinct generation of cells subsequently differentiates itself from its predecessors in the developing embryo by expressing only a selection of its full complement of genes, while actively suppressing others…

How nerve wiring self-destructs

Now, researchers at Washington University School of Medicine in St. Louis have found a way the body can remove injured axons, identifying a potential target for new drugs that could prevent the inappropriate loss of axons and maintain nerve function. "Treating axonal degeneration could potentially help a lot of patients because there are so many diseases and conditions where axons are inappropriately lost," says Aaron DiAntonio, MD, PhD, professor of developmental biology. "While this would not be a cure for any of them, the hope is that we could slow the progression of a whole range of diseases by keeping axons healthy." DiAntonio is senior author of the study that appears online May 9 in the journal Cell Reports. …

Genetic variations associated with susceptibility to bacteria linked to stomach disorders

"[H pylori] is the major cause of gastritis (80 percent) and gastroduodenal ulcer disease (15 percent-20 percent) and the only bacterial pathogen believed to cause cancer," according to background information in the article. "H pylori prevalence is as high as 90 percent in some developing countries but 10 percent of a given population is never colonized, regardless of exposure. Genetic factors are hypothesized to confer H pylori susceptibility." Julia Mayerle, M.D., of University Medicine Greifswald, Greifswald, Germany, and colleagues conducted a study to identify genetic loci associated with H pylori seroprevalence…

Potential therapeutic target for Cushing’s disease

The protein, called TR4 (testicular orphan nuclear receptor 4), is one of the human body’s 48 nuclear receptors, a class of proteins found in cells that are responsible for sensing hormones and, in response, regulating the expression of specific genes. Using a genome scan, the Salk team discovered that TR4 regulates a gene that produces adrenocorticotropic hormone (ACTH), which is overproduced by pituitary tumors in Cushing’s disease (CD). …

Immune cells that suppress genital herpes infections identified

The discovery of this subtype of immune cells, called CD8+ T cells, opens a new avenue of research to develop a vaccine to prevent and treat herpes simplex virus type 2, or HSV-2. Identifying these T cells’ specific molecular targets, called epitopes, is the next step in developing a vaccine. The findings are described in the May 8 advance online edition of Nature…

Adult cells transformed into early-stage nerve cells, bypassing the pluripotent stem cell stage

Bypassing the ultra-flexible iPSC stage was a key advantage, says senior author Su-Chun Zhang, a professor of neuroscience and neurology. "IPSC cells can generate any cell type, which could be a problem for cell-based therapy to repair damage due to disease or injury in the nervous system." In particular, the absence of iPSC cells rules out the formation of tumors by pluripotent cells in the recipient, a major concern involving stem cell therapy. A second advance comes from the virus that delivers genes to reprogram the adult skin cells into a different and more flexible form…

New target for personalized cancer therapy

The research team has pinpointed the cancer abnormality to a mutation in a gene called PIK3CA that results in a mutant protein, which may be an early cancer switch. By disrupting the mutated signaling pathway, the Case Western Reserve team, led by John Wang, PhD, inhibited the growth of cancer cells, opening the possibility to new cancer therapies. Their findings, "Gain of interaction with IRS1 by p110 helical domain mutants is crucial for their oncogenic functions," was published on May 2 in the journal Cancer Cell. Cancer arises from a single cell, which has mutated in a small number of genes because of random errors in the DNA replication process…