BioPAX pathway converted from "FOXOA2-, MAFA-, and PAX6-dependent synthesis of PDX1 protein" in the Reactome database. FOXOA2-, MAFA-, and PAX6-dependent synthesis of PDX1 protein FOXOA2-, MAFA-, and PAX6-dependent synthesis of PDX1 protein The PDX1 (IPF1) gene is transcribed, its mRNA is translated, and the protein product is transported to the nucleus. PDX1 transcription is positively regulated by the activities of the FOXA2, MAFA, and PAX6 transcription factors. It is negatively regulated by FOXO1A, so events that deplete the nucleoplasmic pool of FOXO1A increase expression of PDX1. These events and interactions have not been studied directly in humans, but are inferred from corresponding ones worked out in the mouse. Authored: Ferrer, J, Tello-Ruiz, MK, 2008-05-23 Reviewed: Jensen, J, 2008-05-12 21:46:53 Edited: D'Eustachio, P, 2008-05-12 21:43:33 Reactome DB_ID: 9606088 1 nucleoplasm GO 0005654 ENSEMBL:ENSG00000139515 PDX1 IPF1 PDX1 STF1 Reactome Homo sapiens NCBI Taxonomy 9606 ENSEMBL ENSG00000139515 Reactome DB_ID: 211179 1 UniProt:P52945 PDX1 PDX1 IPF1 PDX1 STF1 FUNCTION Activates insulin, somatostatin, glucokinase, islet amyloid polypeptide and glucose transporter type 2 gene transcription. Particularly involved in glucose-dependent regulation of insulin gene transcription. As part of a PDX1:PBX1b:MEIS2b complex in pancreatic acinar cells is involved in the transcriptional activation of the ELA1 enhancer; the complex binds to the enhancer B element and cooperates with the transcription factor 1 complex (PTF1) bound to the enhancer A element. Binds preferentially the DNA motif 5'-[CT]TAAT[TG]-3'. During development, specifies the early pancreatic epithelium, permitting its proliferation, branching and subsequent differentiation. At adult stage, required for maintaining the hormone-producing phenotype of the beta-cell.SUBUNIT Interacts with the basic helix-loop-helix domains of TCF3(E47) and NEUROD1 and with HMG-I(Y). Interacts with SPOP (By similarity). Interacts with the methyltransferase SETD7. Part of a PDX1:PBX1b:MEIS2b complex.TISSUE SPECIFICITY Duodenum and pancreas (Langerhans islet beta cells and small subsets of endocrine non-beta-cells, at low levels in acinar cells).DOMAIN The Antp-type hexapeptide mediates heterodimerization with PBX on a regulatory element of the somatostatin promoter.DOMAIN The homeodomain, which contains the nuclear localization signal, not only mediates DNA-binding, but also acts as a protein-protein interaction domain for TCF3(E47), NEUROD1 and HMG-I(Y).PTM Phosphorylated by the SAPK2 pathway at high intracellular glucose concentration. Phosphorylated by HIPK2 on Ser-268 upon glucose accumulation. This phosphorylation mediates subnuclear localization shifting. Phosphorylation by PASK may lead to translocation into the cytosol (By similarity).MISCELLANEOUS According to PubMed:16141209, it may be methylated by SETD7 in vitro. However, the relevance of methylation is unsure in vivo.SIMILARITY Belongs to the Antp homeobox family. IPF1/XlHbox-8 subfamily. UniProt P52945 Chain Coordinates 1 EQUAL 283 EQUAL Reactome Database ID Release 82 211272 Database identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome R-HSA-211272 3 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: ACTIVATION Reactome Database ID Release 82 211277 Database identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome R-HSA-211277 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome DB_ID: 211275 UniProt:Q9Y261 FOXA2 FOXA2 HNF3B TCF3B FOXA2 FUNCTION Transcription factor that is involved in embryonic development, establishment of tissue-specific gene expression and regulation of gene expression in differentiated tissues. Is thought to act as a 'pioneer' factor opening the compacted chromatin for other proteins through interactions with nucleosomal core histones and thereby replacing linker histones at target enhancer and/or promoter sites. Binds DNA with the consensus sequence 5'-[AC]A[AT]T[AG]TT[GT][AG][CT]T[CT]-3' (By similarity). In embryonic development is required for notochord formation. Involved in the development of multiple endoderm-derived organ systems such as the liver, pancreas and lungs; FOXA1 and FOXA2 seem to have at least in part redundant roles. Originally described as a transcription activator for a number of liver genes such as AFP, albumin, tyrosine aminotransferase, PEPCK, etc. Interacts with the cis-acting regulatory regions of these genes. Involved in glucose homeostasis; regulates the expression of genes important for glucose sensing in pancreatic beta-cells and glucose homeostasis. Involved in regulation of fat metabolism. Binds to fibrinogen beta promoter and is involved in IL6-induced fibrinogen beta transcriptional activation.SUBUNIT Binds DNA as a monomer. Binds TLE1 (By similarity). Interacts with FOXA1 and FOXA3. Interacts with PRKDC.PTM Phosphorylation on Thr-156 abolishes binding to target promoters and subsequent transcription activation upon insulin stimulation. UniProt Q9Y261 1 EQUAL 457 EQUAL INHIBITION Reactome Database ID Release 82 211284 Database identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome R-HSA-211284 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome DB_ID: 199300 UniProt:Q12778 FOXO1 FOXO1 FOXO1A FOXO1 FKHR FUNCTION Transcription factor that is the main target of insulin signaling and regulates metabolic homeostasis in response to oxidative stress (PubMed:10358076, PubMed:12228231, PubMed:15220471, PubMed:15890677, PubMed:18356527, PubMed:19221179, PubMed:20543840, PubMed:21245099). Binds to the insulin response element (IRE) with consensus sequence 5'-TT[G/A]TTTTG-3' and the related Daf-16 family binding element (DBE) with consensus sequence 5'-TT[G/A]TTTAC-3' (PubMed:10358076). Activity suppressed by insulin (PubMed:10358076). Main regulator of redox balance and osteoblast numbers and controls bone mass (By similarity). Orchestrates the endocrine function of the skeleton in regulating glucose metabolism (By similarity). Also acts as a key regulator of chondrogenic commitment of skeletal progenitor cells in response to lipid availability: when lipids levels are low, translocates to the nucleus and promotes expression of SOX9, which induces chondrogenic commitment and suppresses fatty acid oxidation (By similarity). Acts synergistically with ATF4 to suppress osteocalcin/BGLAP activity, increasing glucose levels and triggering glucose intolerance and insulin insensitivity (By similarity). Also suppresses the transcriptional activity of RUNX2, an upstream activator of osteocalcin/BGLAP (By similarity). Acts as an inhibitor of glucose sensing in pancreatic beta cells by acting as a transcription repressor and suppressing expression of PDX1 (By similarity). In hepatocytes, promotes gluconeogenesis by acting together with PPARGC1A and CEBPA to activate the expression of genes such as IGFBP1, G6PC1 and PCK1 (By similarity). Also promotes gluconeogenesis by directly promoting expression of PPARGC1A and G6PC1 (PubMed:17024043). Important regulator of cell death acting downstream of CDK1, PKB/AKT1 and STK4/MST1 (PubMed:18356527, PubMed:19221179). Promotes neural cell death (PubMed:18356527). Mediates insulin action on adipose tissue (By similarity). Regulates the expression of adipogenic genes such as PPARG during preadipocyte differentiation and, adipocyte size and adipose tissue-specific gene expression in response to excessive calorie intake (By similarity). Regulates the transcriptional activity of GADD45A and repair of nitric oxide-damaged DNA in beta-cells (By similarity). Required for the autophagic cell death induction in response to starvation or oxidative stress in a transcription-independent manner (PubMed:20543840). Mediates the function of MLIP in cardiomyocytes hypertrophy and cardiac remodeling (By similarity). Regulates endothelial cell (EC) viability and apoptosis in a PPIA/CYPA-dependent manner via transcription of CCL2 and BCL2L11 which are involved in EC chemotaxis and apoptosis (PubMed:31063815).SUBUNIT Interacts with LRPPRC. Interacts with RUNX2; the interaction inhibits RUNX2 transcriptional activity and mediates the IGF1/insulin-dependent BGLAP expression in osteoblasts Interacts with PPP2R1A; the interaction regulates the dephosphorylation of FOXO1 at Thr-24 and Ser-256 leading to its nuclear import. Interacts (acetylated form) with PPARG. Interacts with XBP1 isoform 2; this interaction is direct and leads to FOXO1 ubiquitination and degradation via the proteasome pathway (By similarity). Interacts with NLK. Interacts with SIRT1; the interaction results in the deacetylation of FOXO1 leading to activation of FOXO1-mediated transcription of genes involved in DNA repair and stress resistance. Binds to CDK1. Interacts with the 14-3-3 proteins, YWHAG and YWHAZ; the interactions require insulin-stimulated phosphorylation on Thr-24, promote nuclear exit and loss of transcriptional activity. Interacts with SKP2; the interaction ubiquitinates FOXO1 leading to its proteosomal degradation. The interaction requires the presence of KRIT1. Interacts (via the C-terminal half) with ATF4 (via its DNA-binding domain); the interaction occurs in osteoblasts, regulates glucose homeostasis via suppression of beta-cell proliferation and subsequent decrease in insulin production. Interacts with PRMT1; the interaction methylates FOXO1, prevents PKB/AKT1 phosphorylation and retains FOXO1 in the nucleus. Interacts with EP300 and CREBBP; the interactions acetylate FOXO1. Interacts with SIRT2; the interaction is disrupted in response to oxidative stress or serum deprivation, leading to increased level of acetylated FOXO1, which promotes stress-induced autophagy by stimulating E1-like activating enzyme ATG7. Interacts (acetylated form) with ATG7; the interaction is increased in response to oxidative stress or serum deprivation and promotes the autophagic process leading to cell death. Interacts (via the Fork-head domain) with CEBPA; the interaction increases when FOXO1 is deacetylated. Interacts with WDFY2. Forms a complex with WDFY2 and AKT1 (By similarity). Interacts with CRY1 (By similarity). Interacts with PPIA/CYPA; the interaction promotes FOXO1 dephosphorylation, nuclear accumulation and transcriptional activity (PubMed:31063815). Interacts with TOX4; FOXO1 is required for full induction of TOX4-dependent activity and the interaction is inhibited by insulin (By similarity).TISSUE SPECIFICITY Ubiquitous.INDUCTION Expression is regulated by KRIT1. Levels of expression also regulated by FOXC1 which binds to a conserved element in the FOXO1 promoter.PTM Phosphorylation by NLK promotes nuclear export and inhibits the transcriptional activity. In response to growth factors, phosphorylation on Thr-24, Ser-256 and Ser-322 by PKB/AKT1 promotes nuclear export and inactivation of transactivational activity. Phosphorylation on Thr-24 is required for binding 14-3-3 proteins. Phosphorylation of Ser-256 decreases DNA-binding activity and promotes the phosphorylation of Thr-24 and Ser-319, permitting phosphorylation of Ser-322 and Ser-325, probably by CDK1, leading to nuclear exclusion and loss of function. Stress signals, such as response to oxygen or nitric oxide, attenuate the PKB/AKT1-mediated phosphorylation leading to nuclear retention. Phosphorylation of Ser-329 is independent of IGF1 and leads to reduced function. Dephosphorylated on Thr-24 and Ser-256 by PP2A in beta-cells under oxidative stress leading to nuclear retention (By similarity). Phosphorylation of Ser-249 by CDK1 disrupts binding of 14-3-3 proteins leading to nuclear accumulation and has no effect on DNA-binding nor transcriptional activity. Phosphorylation by STK4/MST1 on Ser-212, upon oxidative stress, inhibits binding to 14-3-3 proteins and nuclear export. PPIA/CYPA promotes its dephosphorylation on Ser-256 (PubMed:31063815).PTM Ubiquitinated by SKP2. Ubiquitination leads to proteasomal degradation.PTM Methylation inhibits AKT1-mediated phosphorylation at Ser-256 and is increased by oxidative stress.PTM Acetylated (PubMed:20543840, PubMed:15220471, PubMed:15890677, PubMed:18786403). Acetylation at Lys-262, Lys-265 and Lys-274 are necessary for autophagic cell death induction (PubMed:20543840). Deacetylated by SIRT2 in response to oxidative stress or serum deprivation, thereby negatively regulating FOXO1-mediated autophagic cell death (PubMed:20543840). Once in the nucleus, acetylated by CREBBP/EP300 (PubMed:15220471, PubMed:15890677, PubMed:18786403). Acetylation diminishes the interaction with target DNA and attenuates the transcriptional activity. It increases the phosphorylation at Ser-256 (PubMed:15220471, PubMed:15890677, PubMed:18786403). Deacetylation by SIRT1 results in reactivation of the transcriptional activity (PubMed:15220471, PubMed:15890677, PubMed:18786403). Oxidative stress by hydrogen peroxide treatment appears to promote deacetylation and uncoupling of insulin-induced phosphorylation (PubMed:15220471, PubMed:15890677, PubMed:18786403). By contrast, resveratrol acts independently of acetylation (PubMed:15220471, PubMed:15890677, PubMed:18786403). Acetylated at Lys-423, promoting its localization to the nucleus and transcription factor activity (PubMed:25009184). Deacetylation at Lys-423 by SIRT6, promotes its translocation into the cytoplasm, preventing its transcription factor activity (PubMed:25009184). Deacetylation and subsequent inhibition by SIRT6 has different effects depending on cell types: it inhibits gluconeogenesis in hepatocytes, promotes glucose sensing in pancreatic beta-cells and regulates lipid catabolism in brown adipocytes (By similarity). UniProt Q12778 1 EQUAL 655 EQUAL ACTIVATION Reactome Database ID Release 82 211575 Database identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome R-HSA-211575 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome DB_ID: 3009044 UniProt:P26367 PAX6 PAX6 AN2 PAX6 FUNCTION Transcription factor with important functions in the development of the eye, nose, central nervous system and pancreas. Required for the differentiation of pancreatic islet alpha cells (By similarity). Competes with PAX4 in binding to a common element in the glucagon, insulin and somatostatin promoters. Regulates specification of the ventral neuron subtypes by establishing the correct progenitor domains (By similarity). Acts as a transcriptional repressor of NFATC1-mediated gene expression (By similarity).SUBUNIT Interacts with MAF and MAFB (By similarity). Interacts with TRIM11; this interaction leads to ubiquitination and proteasomal degradation, as well as inhibition of transactivation, possibly in part by preventing PAX6 binding to consensus DNA sequences (By similarity). Interacts with TLE6/GRG6 (By similarity).DEVELOPMENTAL STAGE Expressed in the developing eye and brain. Expression in the retina peaks at fetal days 51-60. At 6-week old, in the retina, is predominantly detected in the neural layer (at protein level). At 8- and 10-week old, in the retina, the expression is strongest in the inner and middle layer of the neural part (at protein level).PTM Ubiquitinated by TRIM11, leading to ubiquitination and proteasomal degradation.SIMILARITY Belongs to the paired homeobox family. UniProt P26367 1 EQUAL 422 EQUAL ACTIVATION Reactome Database ID Release 82 211282 Database identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome R-HSA-211282 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: Reactome DB_ID: 211283 UniProt:Q8NHW3 MAFA MAFA MAFA FUNCTION Transcription factor that activates insulin gene expression (PubMed:15993959, PubMed:12011435). Acts synergistically with NEUROD1/BETA2 and PDX1 (PubMed:15993959). Binds the insulin enhancer C1/RIPE3b element (PubMed:12011435). Binds to consensus TRE-type MARE 5'-TGCTGACTCAGCA-3' DNA sequence (PubMed:23148532, PubMed:29339498).SUBUNIT Forms homodimers or heterodimers (PubMed:12011435, PubMed:23148532). Monomers and dimers are able to bind DNA, but the off-rate is faster for monomers (PubMed:23148532). Interacts with NEUROD1 and PDX1 (By similarity). May interact with MAFB, FOS, JUN and PCAF (By similarity).TISSUE SPECIFICITY Expressed in the islets of Langerhans (at protein level).PTM Ubiquitinated, leading to its degradation by the proteasome.PTM Phosphorylated at tyrosines.SIMILARITY Belongs to the bZIP family. Maf subfamily. UniProt Q8NHW3 1 EQUAL 353 EQUAL