A discovery by Penn State College of Medicine researchers refutes an idea widely accepted by scientists and throws new light on how certain genes are regulated by so-called gene switches.
Faulty regulation of genes is a common basis of many human diseases, including many cancers. Understanding gene regulation comes down to describing the components of gene switches and understanding how the various components work together to provide normal switch operation and, therefore, normal gene expression.
This discovery reveals that a protein previously thought to be in the nucleus of the cell actually resides in the cytoplasm, the part of the cell that surrounds and interacts with the nucleus. Also, the study corrects a theory held since 1992 that describes the way the gene switch regulating galactose metabolism operates.
These findings offer a new set of parameters for understanding gene switches as scientists search for the reasons why faulty gene switches cause illness.
The study, titled "Gene activation by interaction of an inhibitor with a cytoplasmic signaling protein," was published today, (June 24) in the online Proceedings of the National Academy of Sciences Early Edition, http://www.pnas.org. It will appear in the June 25, 2002, print edition of the journal.
"Gene switches determine how, when, and to what extent specific genes in the genome are turned on or off or modulated," said James Hopper, Ph.D., professor of biochemistry and molecular biology, Penn State College of Medicine, and principal investigator for the study. "Understanding gene switches is germane to many diseases in humans. If the gene switch breaks down, all of the genes controlled by the switch show abnormal expression."
Abnormal expression may result when the gene's protein is not produced, too much of the protein is produced, or the protein is produced at inappropriate times under inappropriate conditions.