Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rare developmental disorder linked to tumor-suppressing protein, Stanford researchers find

04.08.2014

CHARGE, which affects 1 in 10,000 babies, is an acronym whose letters stand for some of the more common symptoms of the condition: coloboma of the eye, heart defects, atresia of the choanae, retardation of growth and/or development, genital and/or urinary abnormalities, and ear abnormalities and deafness.

Originally, the researchers were examining the tumor-suppressive properties of the protein, called p53, not investigating developmental disorders. But when a mouse model developed a strange set of deficiencies, the researchers followed a trail of clues that led them to link p53 with CHARGE syndrome.

"It was a very big surprise and very intriguing," said Jeanine Van Nostrand, PhD, lead author of a paper describing the research and a former Stanford graduate student, now at The Salk Institute for Biological Studies. "P53 had never before been shown to have a role in CHARGE."

The paper will be published online Aug. 3 in Nature. The senior author is Laura Attardi, PhD, professor of radiation oncology and of genetics.

Cellular quality control regulator

The researchers originally created a mouse model that expressed a mutated form of the protein, known as p53, to investigate the behavior of p53 in suppressing tumors. Mice expressing only the mutated protein survived. But to their surprise, heterozygous mice, or those with one copy of the mutated p53 and one normal copy, developed symptoms of CHARGE and died in utero.

P53 is a cellular quality-control regulator. When it spots an ailing cell, it triggers other proteins to kill the cell or arrest its division. In a developing human or mouse, other proteins switch off p53 so it doesn't inadvertently kill important cells. The mutated form of p53 created by the researchers had a disabled off-switch, but it also couldn't communicate with other proteins to spark the cellular death. Therefore, a mouse containing only the mutated p53 survived to adulthood.

But when mice had one copy of a mutated p53 gene and one normal copy, the resultant proteins formed hybrids. These hybrid p53 proteins couldn't be turned off, but they retained the ability to trigger cellular death. Interestingly, these proteins only affected certain types of cells, causing the symptoms of CHARGE. The results suggest that p53 may play a role in other developmental disorders, Attardi said.

"It really reiterates how carefully p53 must be regulated," Attardi said. "It needs to be turned on at the right time and place. If it's not, it can cause damage."

CHARGE linked to gene mutation

The mechanisms of CHARGE syndrome remain a mystery, although it has been linked to a mutation in a gene called CHD7. Attardi's team examined the connection between p53 and CHD7. They discovered that the CHD7 protein can keep p53 turned off.

By linking p53 with CHARGE, this study elucidates molecular pathways that could be used to develop CHARGE therapies, said co-author Donna Martin, MD, PhD, associate professor of pediatrics and of human genetics at the University of Michigan Medical School and an expert on CHARGE.

###

Additional Stanford authors are former graduate students Colleen Brady, PhD, and Thomas Johnson, MD; postdoctoral scholar Heiyoun Jung, PhD; graduate students Daniel Fuentes, Chieh-Yu Lin and Chien-Jung Lin; Margaret Kozak, a former research assistant; Hannes Vogel, MD, professor of pathology and of pediatrics; Jonathan Bernstein, MD, assistant professor of pediatrics; and Joanna Wysocka, PhD, associate professor of chemical and systems biology and of developmental biology.

Other authors of the study are affiliated with Hôpital Necker-Enfants Malades in Paris, Université Paris Descartes, the Indiana University School of Medicine and the University of Michigan Medical School.

The study was supported by the National Science Foundation; the National Cancer Institute (grant 1F31CA167917); the National Institutes of Health (grants R01GM095555, R01DC009410, HL118087, HL121197 and R01CA140875); the American Heart Association; the March of Dimes Foundation; the American Cancer Society; and the Leukemia & Lymphoma Society.

Information about the Stanford's Department of Radiation Oncology and the Department of Genetics, which also supported the study, is available at http://radonc.stanford.edu and http://genetics.stanford.edu.

The Stanford University School of Medicine consistently ranks among the nation's top medical schools, integrating research, medical education, patient care and community service. For more news about the school, please visit http://mednews.stanford.edu. The medical school is part of Stanford Medicine, which includes Stanford Hospital & Clinics and Lucile Packard Children's Hospital Stanford. For information about all three, please visit http://stanfordmedicine.org/about/news.html.

Print media contact: Rosanne Spector at (650) 725-5374 (manishma@stanford.edu)

Broadcast media contact: M.A. Malone at (650) 723-6912 (mamalone@stanford.edu)

Rosanne Spector | Eurek Alert!

Further reports about: CHARGE Syndrome CHD7 Cancer Medicine death disorder heart defects p53 proteins symptoms

More articles from Life Sciences:

nachricht One step closer to reality
20.04.2018 | Max-Planck-Institut für Entwicklungsbiologie

nachricht The dark side of cichlid fish: from cannibal to caregiver
20.04.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>