Serine/threonine-protein kinase that regulates a number of transcription factors with key roles in cell fate determination. Positive effector of the non-canonical Wnt signaling pathway, acting downstream of WNT5A, MAP3K7/TAK1 and HIPK2. Activation of this pathway causes binding to and phosphorylation of the histone methyltransferase SETDB1. The NLK-SETDB1 complex subsequently interacts with PPARG, leading to methylation of PPARG target promoters at histone H3K9 and transcriptional silencing. The resulting loss of PPARG target gene transcription inhibits adipogenesis and promotes osteoblastogenesis in mesenchymal stem cells (MSCs). Negative regulator of the canonical Wnt/beta-catenin signaling pathway. Binds to and phosphorylates TCF7L2/TCF4 and LEF1, promoting the dissociation of the TCF7L2/LEF1/beta-catenin complex from DNA, as well as the ubiquitination and subsequent proteolysis of LEF1. Together these effects inhibit the transcriptional activation of canonical Wnt/beta-catenin target genes. Negative regulator of the Notch signaling pathway. Binds to and phosphorylates NOTCH1, thereby preventing the formation of a transcriptionally active ternary complex of NOTCH1, RBPJ/RBPSUH and MAML1. Negative regulator of the MYB family of transcription factors. Phosphorylation of MYB leads to its subsequent proteolysis while phosphorylation of MYBL1 and MYBL2 inhibits their interaction with the coactivator CREBBP. Other transcription factors may also be inhibited by direct phosphorylation of CREBBP itself. Acts downstream of IL6 and MAP3K7/TAK1 to phosphorylate STAT3, which is in turn required for activation of NLK by MAP3K7/TAK1. Upon IL1B stimulus, cooperates with ATF5 to activate the transactivation activity of C/EBP subfamily members. Phosphorylates ATF5 but also stabilizes ATF5 protein levels in a kinase-independent manner. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Activated by the non-canonical Wnt signaling pathway, in which WNT5A leads to activation of MAP3K7/TAK1 and HIPK2, which subsequently phosphorylates and activates this protein. Activated by dimerization and subsequent intermolecular autophosphorylation on Thr-298. Other cytokines such as IL6 may also activate this regulatory circuit (By similarity). Homodimer. Homodimerization is required for intermolecular autophosphorylation, kinase activation and nuclear localization (By similarity). May interact with components of cullin-RING-based SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes (By similarity). Interacts with LEF1, MEF2A, MYBL1 and MYBL2 (By similarity). Interacts with the upstream activating kinases HIPK2 and MAP3K7/TAK1. Interaction with MAP3K7/TAK1 seems to be indirect, and may be mediated by other proteins such as STAT3, TAB1 and TAB2. Interacts with and phosphorylates a number of transcription factors including FOXO1, FOXO3, FOXO4, MYB, NOTCH1 and TCF7L2/TCF4. Interacts with DAPK3/ZIPK, and this interaction may disrupt interaction with transcription factors such as TCF7L2/TCF4. Forms a transcriptional repressor complex with CHD7, PPARG and SETDB1. Interacts with RNF138/NARF (By similarity). Interacts with ATF5; the interaction stabilizes ATF5 at the protein level in a kinase-independent manner (By similarity). Predominantly nuclear. A smaller fraction is cytoplasmic (By similarity). Contains a TQE activation loop motif in which autophosphorylation of the threonine residue (Thr-298) is sufficient for kinase activation. This mode of activation contrasts with that of classical MAP kinases, which contain a TXY activation loop motif in which phosphorylation of both the threonine and tyrosine residues is required for kinase activation (By similarity). Phosphorylated on Thr-298. Intermolecular autophosphorylation on Thr-298 activates the enzyme (By similarity). Belongs to the protein kinase superfamily. CMGC Ser/Thr protein kinase family. MAP kinase subfamily.