About
In the Shadel Lab, we study mitochondria, essential organelles inside most cells. Mitochondria are known as the “powerhouses of the cell” because of their key role in generating the high-energy molecule ATP to power virtually all processes in an organism. However, mitochondria do much more than oxidative phosphorylation (OXPHOS) to produce ATP. For example, they are the sites of dozens of other essential biochemical reactions (e.g. heme and iron-sulfur cluster synthesis) and can initiate apoptotic cell death. Mitochondria are also constantly fusing, dividing and moving throughout the cell. Thus, their morphology, motility and dynamics regulate their function. Lastly, mitochondria contain DNA (mtDNA) that is maternally inherited in mammals, usually present at thousands of copies/cell, and, because it encodes thirteen essential subunits of the OXPHOS complexes, causes human diseases and contributes to aging when mutated.
Given the multi-faceted roles of mitochondria, the overarching hypothesis in the Shadel lab is that these amazing organelles are involved in many more processes and pathways than originally thought. Furthermore, we believe they communicate with other organelles within the same cell, and elicit direct intracellular, intercellular, and even peripheral signaling events. Thus, a major emphasize of our work is to understand the nature of these mitochondrial stress-signaling pathways. In doing so, we continue to elucidate novel ways that mitochondria and mtDNA contribute to human diseases, aging and immunity.
On the web
Website: https://shadel.salk.edu/
News: https://www.salk.edu/news-release/mitochondria-are-the-canary-in-the-coal-mine-for-cellular-stress/
People
Gerald Shadel, PhD
Director, San Diego-Nathan Shock Center of Excellence in the Basic Biology of Aging, Audrey Geisel Chair in Biomedical Science, Professor Molecular and Cell BiologyBio
Gerald Shadel studies the basic biology of mitochondria and mtDNA, and, in doing so, has identified novel ways that mitochondria contribute to disease, aging and the immunesystem. He is also interested in understanding how mitochondria are involved in cellular signaling processes. He seeks to identify what the signals are, what pathways they trigger and how they play a part in aging, cancer and metabolic and degenerative diseases. His group takes a multidisciplinary view, exploring mitochondrial function—and dysfunction—via cultured cells, model organisms and other genetic and biochemical approaches.
Shadel has elucidated context-specific ways that mitochondria and the reactive oxygen species (ROS) they produce are involved in the neurodegenerative disease ataxia-telangiectasia (A-T), maternally inherited deafness, aging and cancer.
He also discovered that mtDNA, which is derived from an ancient bacterium, can trigger the immune system if exposed to the rest of the cell, causing antiviral and other defensive responses. Image courtesy Nature Reviews Immunology.
He is currently studying adaptive responses to mitochondrial stress in mammals, based on his discovery in yeast that mitochondrial ROS signals induce changes in gene expression in the cell nucleus that extend this organism’s life span.
On The Web
Greg Shadel at Salk Institute: https://www.salk.edu/scientist/gerald-shadel/