Dual-specificity kinase which possesses both serine/ threonine and tyrosine kinase activities. Enhances the transcriptional activity of TCF1/HNF1A and FOXO1. Inhibits epithelial cell migration. Mediates colon carcinoma cell survival in mitogen-poor environments.
Mirk/Dyrk1B is an arginine-directed serine/threonine protein kinase that is expressed at low levels in most normal tissues but at elevated levels in many tumor cell lines and in normal skeletal muscle. Colon carcinoma cell lines stably overexpressing Mirk proliferated in serum-free medium, but the mechanism of Mirk action is unknown. DCoHm (dimerization cofactor of hepatocyte nuclear factor 1alpha ( HNF1alpha) from muscle), a novel gene of the DCoH family with 78% amino acid identity to DCoH, was identified as a Mirk-binding protein by yeast two-hybrid analysis and cloned. Mirk co-immunoprecipitated with DCoHm and bound to DCoHm in glutathione S-transferase pull-down assays. DCoH stabilizes HNF1alpha as a dimer and enhances its transcriptional activity on the beta-fibrinogen promoter reporter, and DCoHm had similar activity. Mirk enhanced HNF1alpha transcriptional activity in a dose-dependent manner, whereas two kinase-inactive Mirk mutants and a Mirk N-terminal deletion mutant did not. Mirk, DCoHm, and HNF1alpha formed a complex. Mirk bound to a specific region within the CREB-binding protein-binding region of HNF1alpha and phosphorylated HNF1alpha at a site adjacent to the Mirk-binding region. Conversely, the HNF1alpha binding domain was located within the first five conserved kinase subdomains of Mirk. Mirk co-immunoprecipitated with the MAPK kinase MKK3, an upstream activator of p38. MKK3 enhanced Mirk kinase activity and the transcriptional activation of HNF1alpha by Mirk, suggesting that Mirk, like p38, is activated by certain environmental stress agents. The Mirk-binding protein DCoH has been shown to be selectively expressed in colon carcinomas but not in normal tissue. Mirk may function as an HNF1alpha transcriptional activator in response to an MKK3-mediated stress signal, and the selective expression of DCoH could restrict the Mirk response to carcinoma cells.
Minibrain-related kinase (Mirk)/Dyrk1B is an arginine-directed serine/threonine kinase that is active in skeletal muscle development but is also expressed in various carcinomas. In the current study, the Met adaptor protein Ran-binding protein M (RanBPM) was identified as a Mirk-binding protein by yeast two-hybrid analysis. The Mirk-RanBPM association was confirmed by glutathione S-transferase pull-down assays, co-immunoprecipitation studies, and in vivo cross-linking. Met plays an important role in tumor cell invasion and cell migration. RanBPM has been reported to bind to the tyrosine kinase domain of the hepatocyte growth factor (HGF) receptor Met, enhance Met downstream signaling, and enhance HGF-induced A704 kidney carcinoma cell invasion (Wang, D., Li, Z., Messing, E. M., and Wu, G. (2002) J. Biol. Chem. 277, 36216-36222). We made a stable Mirk-inducible subline from nontransformed Mv1Lu lung epithelial cells and now demonstrate that induction of Mirk inhibited the migration of these cells in wounding experiments and inhibited their invasion through polycarbonate Transwell filters. Furthermore the ability of Mirk to inhibit Mv1Lu cell migration was attenuated when cells were exposed to HGF or to elevated levels of transiently expressed RanBPM. RanBPM inhibited the kinase activity of Mirk/Dyrk1B and Dyrk1A. In addition, RanBPM and HGF inhibited the function of Mirk as a transcriptional coactivator. Our findings suggest that Mirk plays a role in modulating cell migration through opposing the action of the Met signaling cascade adaptor protein RanBPM.
We have cloned a novel gene mirk (minibrain-related kinase) encoding a protein kinase that enables colon carcinoma cells to survive under certain stress conditions. Mirk is a mitogen-activated protein kinase substrate but is down-regulated by activated extracellular signal-regulated kinases (erks) in vivo. Mirk contains a PEST region characteristic of rapidly turned over proteins and is broken down to a Mr 57,000 form only in the nucleus. In each of three colon carcinoma cell lines, mirk levels were increased 20-fold when erk activation was blocked by the MEK inhibitor PD98059 in serum-free medium. Addition of IGF-I to activate erks blocked this increase. Mirk was stably overexpressed in two colon carcinoma cell lines to attain levels seen in colon cancers. Each of five mirk transfectants proliferated when switched to serum-free medium and regained rapid growth when serum was restored, whereas five vector control transfectants and three kinase-dead mutant mirk transfectants did not. mirk mRNA levels were elevated in several types of carcinomas, and mirk protein was detected in each of seven colon carcinoma cell lines. mirk was expressed at a higher protein level in Western blots from three of eight colon cancers compared with paired normal colon tissue, suggesting that mirk plays a role in the evolution of a subset of colon cancers. mirk is not mutated in colon carcinomas. Mirk may mediate tumor cell survival in mitogen-poor environments or early in colon cancer development before many autocrine growth factors have been induced.
Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).
Evidence
1:
Inferred from Physical InteractionUniProtKB
Glycogen synthase, a key enzyme in the regulation of glycogen synthesis by insulin, is controlled by multisite phosphorylation. Glycogen synthase kinase-3 (GSK-3) phosphorylates four serine residues in the COOH terminus of glycogen synthase. Phosphorylation of one of these residues, Ser(640) (site 3a), causes strong inactivation of glycogen synthase. In previous work, we demonstrated in cell models that site 3a can be phosphorylated by an as yet unidentified protein kinase (3a-kinase) distinct from GSK-3. In the present study, we purified the 3a-kinase from rabbit skeletal muscle and identified one constituent polypeptide as HAN11, a WD40 domain protein with unknown function. Another polypeptide was identified as DYRK1A, a member of the dual-specificity tyrosine phosphorylated and regulated protein kinase (DYRK) family. Two isoforms of DYRK, DYRK1A and DYRK1B, co-immunoprecipitate with HAN11 when coexpressed in COS cells indicating that the proteins interact in mammalian cells. Co-expression of DYRK1A, DYRK1B, or DYRK2 with a series of glycogen synthase mutants with Ser/Ala substitutions at the phosphorylation sites in COS cells revealed that protein kinases cause phosphorylation of site 3a in glycogen synthase. To confirm that DYRKs directly phosphorylate glycogen synthase, recombinant DYRK1A, DYRK2, and glycogen synthase were produced in bacterial cells. In the presence of Mg-ATP, both DYRKs inactivated glycogen synthase by more than 10-fold. The inactivation correlated with phosphorylation of site 3a in glycogen synthase. These results indicate that protein kinase(s) from the DYRK family may be involved in a new mechanism for the regulation of glycogen synthesis.
Evidence
2:
Inferred from Physical InteractionIntAct
Minibrain-related kinase (Mirk)/Dyrk1B is an arginine-directed serine/threonine kinase that is active in skeletal muscle development but is also expressed in various carcinomas. In the current study, the Met adaptor protein Ran-binding protein M (RanBPM) was identified as a Mirk-binding protein by yeast two-hybrid analysis. The Mirk-RanBPM association was confirmed by glutathione S-transferase pull-down assays, co-immunoprecipitation studies, and in vivo cross-linking. Met plays an important role in tumor cell invasion and cell migration. RanBPM has been reported to bind to the tyrosine kinase domain of the hepatocyte growth factor (HGF) receptor Met, enhance Met downstream signaling, and enhance HGF-induced A704 kidney carcinoma cell invasion (Wang, D., Li, Z., Messing, E. M., and Wu, G. (2002) J. Biol. Chem. 277, 36216-36222). We made a stable Mirk-inducible subline from nontransformed Mv1Lu lung epithelial cells and now demonstrate that induction of Mirk inhibited the migration of these cells in wounding experiments and inhibited their invasion through polycarbonate Transwell filters. Furthermore the ability of Mirk to inhibit Mv1Lu cell migration was attenuated when cells were exposed to HGF or to elevated levels of transiently expressed RanBPM. RanBPM inhibited the kinase activity of Mirk/Dyrk1B and Dyrk1A. In addition, RanBPM and HGF inhibited the function of Mirk as a transcriptional coactivator. Our findings suggest that Mirk plays a role in modulating cell migration through opposing the action of the Met signaling cascade adaptor protein RanBPM.
Evidence
3:
Inferred from Physical InteractionUniProtKB
Mirk/Dyrk1B is an arginine-directed serine/threonine protein kinase that is expressed at low levels in most normal tissues but at elevated levels in many tumor cell lines and in normal skeletal muscle. Colon carcinoma cell lines stably overexpressing Mirk proliferated in serum-free medium, but the mechanism of Mirk action is unknown. DCoHm (dimerization cofactor of hepatocyte nuclear factor 1alpha ( HNF1alpha) from muscle), a novel gene of the DCoH family with 78% amino acid identity to DCoH, was identified as a Mirk-binding protein by yeast two-hybrid analysis and cloned. Mirk co-immunoprecipitated with DCoHm and bound to DCoHm in glutathione S-transferase pull-down assays. DCoH stabilizes HNF1alpha as a dimer and enhances its transcriptional activity on the beta-fibrinogen promoter reporter, and DCoHm had similar activity. Mirk enhanced HNF1alpha transcriptional activity in a dose-dependent manner, whereas two kinase-inactive Mirk mutants and a Mirk N-terminal deletion mutant did not. Mirk, DCoHm, and HNF1alpha formed a complex. Mirk bound to a specific region within the CREB-binding protein-binding region of HNF1alpha and phosphorylated HNF1alpha at a site adjacent to the Mirk-binding region. Conversely, the HNF1alpha binding domain was located within the first five conserved kinase subdomains of Mirk. Mirk co-immunoprecipitated with the MAPK kinase MKK3, an upstream activator of p38. MKK3 enhanced Mirk kinase activity and the transcriptional activation of HNF1alpha by Mirk, suggesting that Mirk, like p38, is activated by certain environmental stress agents. The Mirk-binding protein DCoH has been shown to be selectively expressed in colon carcinomas but not in normal tissue. Mirk may function as an HNF1alpha transcriptional activator in response to an MKK3-mediated stress signal, and the selective expression of DCoH could restrict the Mirk response to carcinoma cells.
Mirk/Dyrk1B is an arginine-directed serine/threonine protein kinase that is expressed at low levels in most normal tissues but at elevated levels in many tumor cell lines and in normal skeletal muscle. Colon carcinoma cell lines stably overexpressing Mirk proliferated in serum-free medium, but the mechanism of Mirk action is unknown. DCoHm (dimerization cofactor of hepatocyte nuclear factor 1alpha ( HNF1alpha) from muscle), a novel gene of the DCoH family with 78% amino acid identity to DCoH, was identified as a Mirk-binding protein by yeast two-hybrid analysis and cloned. Mirk co-immunoprecipitated with DCoHm and bound to DCoHm in glutathione S-transferase pull-down assays. DCoH stabilizes HNF1alpha as a dimer and enhances its transcriptional activity on the beta-fibrinogen promoter reporter, and DCoHm had similar activity. Mirk enhanced HNF1alpha transcriptional activity in a dose-dependent manner, whereas two kinase-inactive Mirk mutants and a Mirk N-terminal deletion mutant did not. Mirk, DCoHm, and HNF1alpha formed a complex. Mirk bound to a specific region within the CREB-binding protein-binding region of HNF1alpha and phosphorylated HNF1alpha at a site adjacent to the Mirk-binding region. Conversely, the HNF1alpha binding domain was located within the first five conserved kinase subdomains of Mirk. Mirk co-immunoprecipitated with the MAPK kinase MKK3, an upstream activator of p38. MKK3 enhanced Mirk kinase activity and the transcriptional activation of HNF1alpha by Mirk, suggesting that Mirk, like p38, is activated by certain environmental stress agents. The Mirk-binding protein DCoH has been shown to be selectively expressed in colon carcinomas but not in normal tissue. Mirk may function as an HNF1alpha transcriptional activator in response to an MKK3-mediated stress signal, and the selective expression of DCoH could restrict the Mirk response to carcinoma cells.
Catalysis of the reactions: ATP + a protein serine = ADP + protein serine phosphate; ATP + a protein threonine = ADP + protein threonine phosphate; and ATP + a protein tyrosine = ADP + protein tyrosine phosphate.
Interacting selectively and non-covalently with a activating transcription factor and also with the basal transcription machinery in order to increase the frequency, rate or extent of transcription. Cofactors generally do not bind DNA, but rather mediate protein-protein interactions between activating transcription factors and the basal transcription machinery.
Mirk/Dyrk1B is an arginine-directed serine/threonine protein kinase that is expressed at low levels in most normal tissues but at elevated levels in many tumor cell lines and in normal skeletal muscle. Colon carcinoma cell lines stably overexpressing Mirk proliferated in serum-free medium, but the mechanism of Mirk action is unknown. DCoHm (dimerization cofactor of hepatocyte nuclear factor 1alpha ( HNF1alpha) from muscle), a novel gene of the DCoH family with 78% amino acid identity to DCoH, was identified as a Mirk-binding protein by yeast two-hybrid analysis and cloned. Mirk co-immunoprecipitated with DCoHm and bound to DCoHm in glutathione S-transferase pull-down assays. DCoH stabilizes HNF1alpha as a dimer and enhances its transcriptional activity on the beta-fibrinogen promoter reporter, and DCoHm had similar activity. Mirk enhanced HNF1alpha transcriptional activity in a dose-dependent manner, whereas two kinase-inactive Mirk mutants and a Mirk N-terminal deletion mutant did not. Mirk, DCoHm, and HNF1alpha formed a complex. Mirk bound to a specific region within the CREB-binding protein-binding region of HNF1alpha and phosphorylated HNF1alpha at a site adjacent to the Mirk-binding region. Conversely, the HNF1alpha binding domain was located within the first five conserved kinase subdomains of Mirk. Mirk co-immunoprecipitated with the MAPK kinase MKK3, an upstream activator of p38. MKK3 enhanced Mirk kinase activity and the transcriptional activation of HNF1alpha by Mirk, suggesting that Mirk, like p38, is activated by certain environmental stress agents. The Mirk-binding protein DCoH has been shown to be selectively expressed in colon carcinomas but not in normal tissue. Mirk may function as an HNF1alpha transcriptional activator in response to an MKK3-mediated stress signal, and the selective expression of DCoH could restrict the Mirk response to carcinoma cells.
Mirk/Dyrk1B is an arginine-directed serine/threonine protein kinase that is expressed at low levels in most normal tissues but at elevated levels in many tumor cell lines and in normal skeletal muscle. Colon carcinoma cell lines stably overexpressing Mirk proliferated in serum-free medium, but the mechanism of Mirk action is unknown. DCoHm (dimerization cofactor of hepatocyte nuclear factor 1alpha ( HNF1alpha) from muscle), a novel gene of the DCoH family with 78% amino acid identity to DCoH, was identified as a Mirk-binding protein by yeast two-hybrid analysis and cloned. Mirk co-immunoprecipitated with DCoHm and bound to DCoHm in glutathione S-transferase pull-down assays. DCoH stabilizes HNF1alpha as a dimer and enhances its transcriptional activity on the beta-fibrinogen promoter reporter, and DCoHm had similar activity. Mirk enhanced HNF1alpha transcriptional activity in a dose-dependent manner, whereas two kinase-inactive Mirk mutants and a Mirk N-terminal deletion mutant did not. Mirk, DCoHm, and HNF1alpha formed a complex. Mirk bound to a specific region within the CREB-binding protein-binding region of HNF1alpha and phosphorylated HNF1alpha at a site adjacent to the Mirk-binding region. Conversely, the HNF1alpha binding domain was located within the first five conserved kinase subdomains of Mirk. Mirk co-immunoprecipitated with the MAPK kinase MKK3, an upstream activator of p38. MKK3 enhanced Mirk kinase activity and the transcriptional activation of HNF1alpha by Mirk, suggesting that Mirk, like p38, is activated by certain environmental stress agents. The Mirk-binding protein DCoH has been shown to be selectively expressed in colon carcinomas but not in normal tissue. Mirk may function as an HNF1alpha transcriptional activator in response to an MKK3-mediated stress signal, and the selective expression of DCoH could restrict the Mirk response to carcinoma cells.
Mirk/Dyrk1B is an arginine-directed serine/threonine protein kinase that is expressed at low levels in most normal tissues but at elevated levels in many tumor cell lines and in normal skeletal muscle. Colon carcinoma cell lines stably overexpressing Mirk proliferated in serum-free medium, but the mechanism of Mirk action is unknown. DCoHm (dimerization cofactor of hepatocyte nuclear factor 1alpha ( HNF1alpha) from muscle), a novel gene of the DCoH family with 78% amino acid identity to DCoH, was identified as a Mirk-binding protein by yeast two-hybrid analysis and cloned. Mirk co-immunoprecipitated with DCoHm and bound to DCoHm in glutathione S-transferase pull-down assays. DCoH stabilizes HNF1alpha as a dimer and enhances its transcriptional activity on the beta-fibrinogen promoter reporter, and DCoHm had similar activity. Mirk enhanced HNF1alpha transcriptional activity in a dose-dependent manner, whereas two kinase-inactive Mirk mutants and a Mirk N-terminal deletion mutant did not. Mirk, DCoHm, and HNF1alpha formed a complex. Mirk bound to a specific region within the CREB-binding protein-binding region of HNF1alpha and phosphorylated HNF1alpha at a site adjacent to the Mirk-binding region. Conversely, the HNF1alpha binding domain was located within the first five conserved kinase subdomains of Mirk. Mirk co-immunoprecipitated with the MAPK kinase MKK3, an upstream activator of p38. MKK3 enhanced Mirk kinase activity and the transcriptional activation of HNF1alpha by Mirk, suggesting that Mirk, like p38, is activated by certain environmental stress agents. The Mirk-binding protein DCoH has been shown to be selectively expressed in colon carcinomas but not in normal tissue. Mirk may function as an HNF1alpha transcriptional activator in response to an MKK3-mediated stress signal, and the selective expression of DCoH could restrict the Mirk response to carcinoma cells.
Protein which catalyzes the phosphorylation of serine or threonine residues on target proteins by using ATP as phosphate donor. Such phosphorylation may cause changes in the function of the target protein. Protein kinases share a conserved catalytic core common to both serine/ threonine and tyrosine protein kinases.
Enzyme which catalyzes the transfer of the terminal phosphate of ATP to a specific tyrosine residue on its target protein. Many of these kinases play significant roles in development and cell division. Tyrosine-protein kinases can be divided into two subfamilies: receptor tyrosine kinases, which have an intracellular tyrosine kinase domain, a transmembrane domain and an extracellular ligand-binding domain; and non-receptor (cytoplasmic) tyrosine kinases, which are soluble, cytoplasmic kinases.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.