Relationship between oxidative stress and lifespan in Daphnia pulex.

Macromolecular damage leading to cell, tissue and ultimately organ dysfunction is a major contributor to aging. Intracellular reactive oxygen species (ROS) resulting from normal metabolism cause most damage to macromolecules and the mitochondria play a central role in this process as they are the principle source of ROS. The relationship between naturally occurring variations in the mitochondrial (MT) genomes leading to correspondingly less or more ROS and macromolecular damage that changes the rate of aging associated organismal decline remains relatively unexplored.

Regulation of PKR activation and apoptosis during oxidative stress by TRBP phosphorylation.

Transactivation response element RNA-binding protein (TRBP or TARBP2) originally identified as a pro-viral cellular protein in human immunodeficiency virus (HIV) replication is also a regulator of microRNA biogenesis and cellular stress response. TRBP inhibits the catalytic activity of interferon-induced double-stranded RNA (dsRNA)-activated protein kinase (PKR) during viral infections and cell stress thereby regulating stress-induced signaling pathways. During cellular stress, PKR is catalytically activated transiently by its protein activator PACT and TRBP inhibits PKR to bring about a timely cellular recovery.