ROS-regulated signaling pathways. Simplified diagram representing major ROS regulated signaling pathways. ROS can influence the pathways either positively or negatively. ROS necessary for regulation of signaling pathways are mostly generated through specific enzymatic reactions as well as due to the changes in cellular metabolic activity leading to altered ROS production. DAG, diacylglycerol; ERK, extracellular signal-regulated kinase; FAK, focal adhesion kinase; GP, G-protein; GPCR, G-protein coupled receptor; Grb2, growth factor receptor-bound protein 2; HIF-1α, hypoxia-inducible factor-1α; IκB, inhibitor of NF-κB; IKK, IκB kinase; MEK, MAPK/ERK kinase; MKP3, mitogen-activated protein (MAP) kinasephosphatase/dual specificity protein phosphatase-6; PHD, prolyl hydroxylase; PI3K, phosphatidylinositol 3-kinases; PI3P, phosphatidylinositol 3-phosphate; PKB/Akt, proteinkinase B; PKC, protein kinase C; PTEN, phosphatase and tensin homolog deleted on chromosome 10; Raf, ras attachement factor; Ras, Rat sarcoma; RTK, receptor tyrosinekinase; SOS, son of sevenless; Shc, SHC-transforming protein; Src, sarcoma.ETC, electron transport chain; NF-κB, nuclear factor kappa B; NOX, NADPH oxidase subunit; PKC, protein kinase C; PPAR, peroxisome proliferator-activated receptor; SOD,superoxide dismutase; TCA, tricarboxylic acid (Corlach et al., 2015).