In experiments with mice genetically prone to develop polyps, researchers discovered that animals carrying one copy of the damaged gene, Atp5a1, had about 90 percent fewer polyps in the small intestine and colon. Because people with large numbers of such polyps are at significantly higher risk to develop colon cancer, the finding may provide new ways to diagnose, prevent and treat colon cancer, the scientists say. They report their findings March 22, 2007 online in the journal Genome Research.
The researchers, led by Arthur Buchberg, Ph.D., and Linda Siracusa, Ph.D., both associate professors of microbiology and immunology at Jefferson Medical College of Thomas Jefferson University in Philadelphia, studied a type of mice called Min (multiple intestinal neoplasia). Such mice carry mutations in the Apc gene, which causes the development of intestinal tumors in mice. An alteration in the corresponding human gene, APC, is the first step in most cases of the development of colon polyps and the majority of colorectal cancers.
It turns out that Atp5a1, which is crucial for the cell’s energy production, is also a “modifier” gene. Modifier genes play roles in individual susceptibility to cancers. “Modifier genes alter a phenotype dictated by other genes,” explains Dr. Siracusa. “If a person inherits a mutation in the APC gene, a modifier gene can make that number of polyps – and tumors – either higher or lower, and can mean a person is more prone or resistant to developing polyps and tumors.”
In earlier work, the husband and wife team had identified the general region on the chromosome for the mutation. “Now, we’ve identified the gene and it’s very important – it encodes a subunit of the ATP synthase protein, which is known as the molecular motor in the mitochondria, and responsible for the production of ATP and energy in cells,” says Dr. Buchberg. They have dubbed Atp5a1 “Mom2,” for Modifier of Min 2 gene, having previously identified the first modifier of Min mice, Mom1.
“No one as far as we know has ever found a mutation in this gene,” says Dr. Siracusa, noting that both gene mutations – Apc and Atp5a1 – are on mouse chromosome 18. “If the other normal chromosome is lost for some reason, or mice have two copies of the mutant Atp5a1, they die in embryonic development, presumably because the cells lack an energy source.”
The corresponding human gene, ATP5A1, is also located on chromosome 18, in a region that sometimes shows genetic mutations in colon tumors.
Steve Benowitz | EurekAlert!
Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides
16.07.2018 | Tokyo Institute of Technology
The secret sulfate code that lets the bad Tau in
16.07.2018 | American Society for Biochemistry and Molecular Biology
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences