Post-translational modification of proteins during intermittent hypoxia.

Post-translational modification (PTM) is one of the mechanisms by which protein function is regulated by chronic hypoxia. This article presents an overview of recent findings on PTM of proteins induced by chronic intermittent hypoxia (CIH) which is experienced by humans with sleep disordered breathing resulting in autonomic abnormalities. The analysis of PTM of proteins involves electrophoretic separation of tissue or cellular proteins followed by immunolabeling using antibodies specific to native and post-translationally modified forms. Recent results demonstrate that CIH, depending on the pattern, duration and severity of hypoxia, alters the state of phosphorylation of a subset of proteins associated with transcriptional factor activation, signaling pathways and neurotransmitter synthesis via activation of appropriate enzymatic machinery that catalyzes specific phosphorylation reactions. Investigation pertaining to PTMs associated with CIH is at its infant stage and future application of high throughput proteomics techniques are necessary to unravel other important PTMs associated with various critical metabolic and signaling pathways that are activated by intermittent hypoxia.