Mitochondria are subcellular organelles that function as "power plants]for the cell, generating energy in the form of ATP from glucose, oxygen, and other molecules. Thought to have arisen about 2 billion years ago when an aerobic bacterium invaded the primitive eukaryotic cell, they have their own DNA, undergo fission and fusion independently, and play an important role in programmed cell death. Written and edited by experts in the field, this collection from Cold Spring Harbor Perspectives in Biology discusses the evolution of mitochondria, their functions in cells, and the numerous diseases in which mitochondrial dysfunction is implicated. The contributors also examine mitochondrial biogenesis, the molecular mechanisms underlying fission and fusion, how proteins are imported from the cytoplasm, and the organization of the mitochondrial DNA. This book includes chapters covering the involvement of mitochondria in Parkinson's disease, encephalopathies, tumorigenesis, muscular dystrophy, and other diseases, as well as aging. It is thus a vital reference for all cell and molecular biologists, as well as researchers working on muscle and neurodegenerative diseases, the role of metabolism in aging, and cancer.