Kinase signalling pathways are crucial in the control of cell growth and behaviour.
PKB isoforms are overexpressed in human cancers. PKB can also protect cells from apoptosis. PtdIns 3-kinases play a major role in activating PKB in mammals. This signalling pathway is crucial and defects in it can lead to many diseases in humans from insulin related problems to cancers. There was, until recently, a missing step in the pathway in that the link between the PtdIns 3-kinases and PKB was not direct, thus there had to be another gene involved.