New gene-silencing enzyme discovered: Implications seen for treating aggressi...( PHILADELPHIA

New gene-silencing enzyme discovered: Implications seen for treating aggressive cancers

PHILADELPHIA - Although the human genome is estimated to contain about 35,000 genes, only a fraction of these genes are turned on in a given cell type under normal circumstances. Precise control of gene expression is essential; many cancers have been linked to the improper activation of genes that should remain repressed, or silenced.

Now, researchers at The Wistar Institute report the identification of a new enzyme that is required for the silencing of certain genes. The enzyme functions by placing a molecular marker on a gene that causes the gene to be silenced. When this molecular marker is lost, certain genes may be improperly reactivated, which can result in cancer. Discovery of the enzyme could lead to new cancer therapies. A report on the research appears in the April 15 issue of Genes and Development.

"In this study we showed that when this enzyme is active at a particular gene, it places a molecular marker on the gene," says Frank J. Rauscher III, Ph.D., a professor at The Wistar Institute and deputy director of The Wistar Institute Cancer Center. "This molecular marker is crucial in silencing sets of genes."

The molecular marker is the methylation, or addition of a methyl group, to the DNA packaging proteins called histones on the gene that is to be silenced. When this molecular marker is lost, certain genes are no longer silenced but are instead reactivated, which may result in cancer. For instance, Rauscher notes that it has recently been shown that when you lose this molecular marker on a particular set of genes, a normally nonaggressive breast cancer can become very aggressive and metastatic.

"Now that we have found a new enzyme that is required for the silencing of certain genes," Rauscher says, "we believe it will be possible to create specific drugs that can either repress or activate gene expression through the targeting of this enzyme. This could lead to therapies for cancer, specifically for controlling the met
'"/>

Contact: Marion Wyce
wyce@wistar.upenn.edu
215-898-3943
The Wistar Institute
14-Apr-2002

Page: 1 2
Related biology news :

1. Scientists find they can tap gene-silencing process to reveal parts of genetic machinery
2. Anthrax enzyme images reveal secrets of antibiotic resistance, suggest new drug design
3. First glimpse of DNA binding to viral enzyme
4. Two enzymes key to calorie-burning, Brown research shows
5. Argonne scientists determine structure of staph, anthrax enzyme
6. Brain serotonin enzyme finding might explain psychiatric disorders
7. Study finds plant enzyme function changes with location in cell
8. Basic RNA enzyme research promises single-molecule biosensors
9. Molecule that blocks key bacterial enzyme may lead to new antibiotics
10. Study finds first evidence COX-2 enzymes can regulate DNA damage
11. UNC scientists block cellular enzyme activity involved in cancer progression

Post Your Comments: