Molecular biologist discusses role of autophagy
Autophagy, the process of self-digestion of cell components through the action of enzymes within a cell, plays a vital role in cell maintenance and development, but in recent years has also been linked to a growing number of human diseases, including neurodegenerative conditions, cardiovascular disease and breast cancer.
In the Dec. 1, 2000 issue of the journal Science, UCSD professor of cellular and molecular medicine and Howard Hughes Medical Institute investigator Scott D. Emr, Ph.D., reviews recent findings regarding autophagy and advances made in identifying its molecular components.
Along with co-author Daniel J. Klionsky from the University of Michigan, Emr notes that autophagy, the breakdown and recycling of cellular material, is seen in yeast, plants and animals. Although first identified more than 20 years ago, scientific interest in autophagy was fairly modest until the identification about five years ago of several of the molecular components underlying this important process. Since then, some 30 genes have been identified as part of the autophagy pathway. Within the past two years, researchers have identified a link between decreased levels of one of these genes, called beclin 1, and breast cancer.
There are many lines of evidence that connect autophagy to human disease, Emr says. Lower levels of autophagy genes have been linked to cancer and heart disease, while elevated expression of autophagy is associated with neurodegenerative diseases such as Parkinsons.
In the Science review, Emr and Klionsky note that several questions remain for researchers, including the mechanism by which cells sense the need for autophagy and the specific roles of genes within the autophagy pathway.