This gene encodes a serine/threonine protein kinase called phosphoinositide-dependent kinase 1 (PDPK1) which is integral to the function of the PI3-K/Akt signaling pathway. PDPK1 plays a central role in the transduction of signals from insulin by providing the activating phosphorylation to PKB/AKT1, thus propagating the signal to downstream targets controlling cell proliferation and survival, as well as glucose and amino acid uptake and storage. It also negatively regulates the TGF-β-induced signaling by: modulating the association of SMAD3 and SMAD7 with TGF-beta receptor, phosphorylating SMAD2, SMAD3, SMAD4 and SMAD7, preventing the nuclear translocation of SMAD3 and SMAD4 and the translocation of SMAD7 from the nucleus to the cytoplasm in response to TGF-beta. Activates the NF-κB pathway via phosphorylation of IKKB.