Autophagy wins the 2016 Nobel Prize in Physiology or Medicine: Breakthroughs in baker's yeast fuel advances in biomedical research

Abstract

Autophagy is an ancient pathway in which parts of eukaryotic cells are self-digested within the lysosome or vacuole. This process has been studied for the past seven decades; however, we are only beginning to gain a molecular understanding of the key steps required for autophagy. Originally characterized as a hormonal and starvation response, we now know that autophagy has a much broader role in biology, including organellar remodeling, protein and organelle quality control, prevention of genotoxic stress, tumor suppression, pathogen elimination, regulation of immunity and inflammation, maternal DNA inheritance, metabolism, and cellular survival. Although autophagy is usually a degradative pathway, it also participates in biosynthetic and secretory processes. Given that autophagy has a fundamental role in many essential cellular functions, it is not surprising that autophagic dysfunction is associated with a wide range of human diseases. Genetic studies in various fungi, particularly Saccharomyces cerevisiae, provided the key initial breakthrough that led to an explosion of research on the basic mechanisms and the physiological connections of autophagy to health and disease. The Nobel Committee has recognized this breakthrough by the awarding of the 2016 Nobel Prize in Physiology or Medicine for research in autophagy.

Fig. 1.

Ultrastructure of autophagy in yeast and mammalian cells. (Left) Electron micrograph of a yeast (S. cerevisiae) cell with autophagic bodies in the vacuole during nitrogen starvation. Reproduced with permission from ref. . (Right) Electron micrograph of a forming autophagosome in an amino acid-starved beclin 1-deficient human breast cancer cell expressing exogenous Beclin 1. Courtesy of X. H. Liang, N. Furuya, Y. Wei, and B. Levine. (Scale bars, 1 μm.)

Fig. 2.

Attendees of the first Gordon Research Conference on “Autophagy in Stress, Development, and Disease” (Colby College, Maine, June 22–27, 2003). In the front row (positions 10–12) are Daniel J. Klionsky, the vice chair; Beth Levine, the chair; and Yoshinori Ohsumi, the 2016 Nobel Laureate in Physiology or Medicine.