Polyglutamylation is a reversible posttranslational modification that is catalyzed by enzymes of the tubulin tyrosine ligase-like (TTLL) family. Here, we found that TTLL11 generates a previously unknown type of polyglutamylation that is initiated by the addition of a glutamate residue to the free C-terminal carboxyl group of a substrate protein. TTLL11 efficiently polyglutamylates the Wnt signaling protein Dishevelled 3 (DVL3), thereby changing the interactome of DVL3. Polyglutamylation increases the capacity of DVL3 to get phosphorylated, to undergo phase separation, and to act in the noncanonical Wnt pathway. Both carboxy-terminal polyglutamylation and the resulting reduction in phase separation capacity of DVL3 can be reverted by the deglutamylating enzyme CCP6, demonstrating a causal relationship between TTLL11-mediated polyglutamylation and phase separation. Thus, C-terminal polyglutamylation represents a new type of posttranslational modification, broadening the range of proteins that can be modified by polyglutamylation and providing the first evidence that polyglutamylation can modulate protein phase separation.

• Klíčová slova
• Dishevelled 3, Noncanonical Wnt Signaling, Polyglutamylation, Protein Condensates, TTLL11,
• MeSH
• fosforylace MeSH
• HEK293 buňky MeSH
• kyselina polyglutamová metabolismus   analogy a deriváty   MeSH
• lidé MeSH
• peptidsynthasy * metabolismus   genetika   MeSH
• posttranslační úpravy proteinů * MeSH
• protein dishevelled * metabolismus   genetika   MeSH
• separace fází MeSH
• signální dráha Wnt MeSH
• signální transdukce MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DVL3 protein, human MeSH Prohlížeč
• kyselina polyglutamová MeSH
• peptidsynthasy * MeSH
• protein dishevelled * MeSH
• tubulin polyglutamylase MeSH Prohlížeč

The casein kinase 1 enzymes (CK1) form a family of serine/threonine kinases with seven CK1 isoforms identified in humans. The most important substrates of CK1 kinases are proteins that act in the regulatory nodes essential for tumorigenesis of hematological malignancies. Among those, the most important are the functions of CK1s in the regulation of Wnt pathways, cell proliferation, apoptosis and autophagy. In this review we summarize the recent developments in the understanding of biology and therapeutic potential of the inhibition of CK1 isoforms in the pathogenesis of chronic lymphocytic leukemia (CLL), other non-Hodgkin lymphomas (NHL), myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and multiple myeloma (MM). CK1δ/ε inhibitors block CLL development in preclinical models via inhibition of WNT-5A/ROR1-driven non-canonical Wnt pathway. While no selective CK1 inhibitors have reached clinical stage to date, one dual PI3Kδ and CK1ε inhibitor, umbralisib, is currently in clinical trials for CLL and NHL patients. In MDS, AML and MM, inhibition of CK1α, acting via activation of p53 pathway, showed promising preclinical activities and the first CK1α inhibitor has now entered the clinical trials.

• Klíčová slova
• AML, CK1α, CK1ε, CLL, MM, WNT pathway, casein kinase 1, inhibitors, leukemia, umbralisib,
• MeSH
• cílená molekulární terapie * MeSH
• hematologické nádory farmakoterapie   enzymologie   patologie   MeSH
• kaseinkinasa I antagonisté a inhibitory   chemie   metabolismus   MeSH
• lidé MeSH
• nádorové kmenové buňky účinky léků   metabolismus   patologie   MeSH
• protinádorové látky farmakologie   terapeutické užití   MeSH
• signální dráha Wnt MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• kaseinkinasa I MeSH
• protinádorové látky MeSH

BACKGROUND: Dishevelled (DVL) is an essential component of the Wnt signaling cascades. Function of DVL is controlled by phosphorylation but the molecular details are missing. DVL3 contains 131 serines and threonines whose phosphorylation generates complex barcodes underlying diverse DVL3 functions. In order to dissect the role of DVL phosphorylation we analyzed the phosphorylation of human DVL3 induced by previously reported (CK1ε, NEK2, PLK1, CK2α, RIPK4, PKCδ) and newly identified (TTBK2, Aurora A) DVL kinases. METHODS: Shotgun proteomics including TiO2 enrichment of phosphorylated peptides followed by liquid chromatography tandem mass spectrometry on immunoprecipitates from HEK293T cells was used to identify and quantify phosphorylation of DVL3 protein induced by 8 kinases. Functional characterization was performed by in-cell analysis of phospho-mimicking/non-phosphorylatable DVL3 mutants and supported by FRET assays and NMR spectroscopy. RESULTS: We used quantitative mass spectrometry and calculated site occupancies and quantified phosphorylation of > 80 residues. Functional validation demonstrated the importance of CK1ε-induced phosphorylation of S268 and S311 for Wnt-3a-induced β-catenin activation. S630-643 cluster phosphorylation by CK1, NEK2 or TTBK2 is essential for even subcellular distribution of DVL3 when induced by CK1 and TTBK2 but not by NEK2. Further investigation showed that NEK2 utilizes a different mechanism to promote even localization of DVL3. NEK2 triggered phosphorylation of PDZ domain at S263 and S280 prevents binding of DVL C-terminus to PDZ and promotes an open conformation of DVL3 that is more prone to even subcellular localization. CONCLUSIONS: We identify unique phosphorylation barcodes associated with DVL function. Our data provide an example of functional synergy between phosphorylation in structured domains and unstructured IDRs that together dictate the biological outcome. Video Abtract.

• Klíčová slova
• CK1, DVL3, Dishevelled, Kinase, Mass spectrometry, NEK2, Phosphorylation, TTBK2, Wnt,
• MeSH
• fosforylace MeSH
• HEK293 buňky MeSH
• hmotnostní spektrometrie MeSH
• kinasy NEK metabolismus   MeSH
• konformace proteinů MeSH
• kultivované buňky MeSH
• lidé MeSH
• protein dishevelled chemie   metabolismus   MeSH
• signální transdukce MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• DVL3 protein, human MeSH Prohlížeč
• kinasy NEK MeSH
• NEK2 protein, human MeSH Prohlížeč
• protein dishevelled MeSH

Dishevelled (DVL) is the key component of the Wnt signaling pathway. Currently, DVL conformational dynamics under native conditions is unknown. To overcome this limitation, we develop the Fluorescein Arsenical Hairpin Binder- (FlAsH-) based FRET in vivo approach to study DVL conformation in living cells. Using this single-cell FRET approach, we demonstrate that (i) Wnt ligands induce open DVL conformation, (ii) DVL variants that are predominantly open, show more even subcellular localization and more efficient membrane recruitment by Frizzled (FZD) and (iii) Casein kinase 1 ɛ (CK1ɛ) has a key regulatory function in DVL conformational dynamics. In silico modeling and in vitro biophysical methods explain how CK1ɛ-specific phosphorylation events control DVL conformations via modulation of the PDZ domain and its interaction with DVL C-terminus. In summary, our study describes an experimental tool for DVL conformational sampling in living cells and elucidates the essential regulatory role of CK1ɛ in DVL conformational dynamics.

• MeSH
• analýza jednotlivých buněk metody   MeSH
• biosenzitivní techniky MeSH
• enzymatické testy metody   MeSH
• fluorescenční mikroskopie metody   MeSH
• fosforylace fyziologie   MeSH
• frizzled receptory metabolismus   MeSH
• genový knockout MeSH
• HEK293 buňky MeSH
• kaseinkinasa Iepsilon genetika   metabolismus   MeSH
• lidé MeSH
• mutageneze cílená MeSH
• oocyty MeSH
• PDZ domény fyziologie   MeSH
• protein dishevelled genetika   metabolismus   MeSH
• rezonanční přenos fluorescenční energie MeSH
• signální dráha Wnt fyziologie   MeSH
• simulace molekulární dynamiky MeSH
• Xenopus laevis MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DVL3 protein, human MeSH Prohlížeč
• frizzled receptory MeSH
• FZD6 protein, human MeSH Prohlížeč
• kaseinkinasa Iepsilon MeSH
• protein dishevelled MeSH

Frizzleds (FZDs) are receptors for secreted lipoglycoproteins of the Wingless/Int-1 (WNT) family, initiating an important signal transduction network in multicellular organisms. FZDs are G protein-coupled receptors (GPCRs), which are well known to be regulated by phosphorylation, leading to specific downstream signaling or receptor desensitization. The role and underlying mechanisms of FZD phosphorylation remain largely unexplored. Here, we investigated the phosphorylation of human FZD6 Using MS analysis and a phospho-state- and -site-specific antibody, we found that Ser-648, located in the FZD6 C terminus, is efficiently phosphorylated by casein kinase 1 ϵ (CK1ϵ) and that this phosphorylation requires the scaffolding protein Dishevelled (DVL). In an overexpression system, DVL1, -2, and -3 promoted CK1ϵ-mediated FZD6 phosphorylation on Ser-648. This DVL activity required an intact DEP domain and FZD-mediated recruitment of this domain to the cell membrane. Substitution of the CK1ϵ-targeted phosphomotif reduced FZD6 surface expression, suggesting that Ser-648 phosphorylation controls membrane trafficking of FZD6 Phospho-Ser-648 FZD6 immunoreactivity in human fallopian tube epithelium was predominantly apical, associated with cilia in a subset of epithelial cells, compared with the total FZD6 protein expression, suggesting that FZD6 phosphorylation contributes to asymmetric localization of receptor function within the cell and to epithelial polarity. Given the key role of FZD6 in planar cell polarity, our results raise the possibility that asymmetric phosphorylation of FZD6 rather than asymmetric protein distribution accounts for polarized receptor signaling.

• Klíčová slova
• Dishevelled, Frizzled, G protein-coupled receptor (GPCR), GRK, WNT, casein kinase 1, cell polarity, cell signaling, phosphorylation, receptor regulation, scaffold protein, serine/threonine protein kinase,
• MeSH
• buněčná membrána metabolismus   MeSH
• epitel metabolismus   MeSH
• fosfoproteiny imunologie   MeSH
• fosforylace MeSH
• frizzled receptory chemie   metabolismus   MeSH
• HEK293 buňky MeSH
• hmotnostní spektrometrie MeSH
• kaseinkinasa I metabolismus   MeSH
• lidé MeSH
• protein dishevelled chemie   fyziologie   MeSH
• protilátky imunologie   MeSH
• sekvence aminokyselin MeSH
• serin metabolismus   MeSH
• signální transdukce MeSH
• vejcovody metabolismus   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fosfoproteiny MeSH
• frizzled receptory MeSH
• FZD6 protein, human MeSH Prohlížeč
• kaseinkinasa I MeSH
• protein dishevelled MeSH
• protilátky MeSH
• serin MeSH

Intrinsically disordered regions (IDRs) are protein regions that lack persistent secondary or tertiary structure under native conditions. IDRs represent >40% of the eukaryotic proteome and play a crucial role in protein-protein interactions. The classical approach for identification of these interaction interfaces is based on mutagenesis combined with biochemical techniques such as coimmunoprecipitation or yeast two-hybrid screening. This approach either provides information of low resolution (large deletions) or very laboriously tries to precisely define the binding epitope via single amino acid substitutions. Here, we report the use of a peptide microarray based on the human scaffold protein AXIN1 for high-throughput and -resolution mapping of binding sites for several AXIN1 interaction partners in vitro For each of the AXIN1-binding partners tested, i.e. casein kinase 1 ϵ (CK1ϵ); c-Myc; peptidyl-prolyl cis/trans isomerase, NIMA-interacting 1 (Pin1); and p53, we found at least three different epitopes, predominantly in the central IDR of AXIN1. We functionally validated the specific AXIN1-CK1ϵ interaction identified here with epitope-mimicking peptides and with AXIN1 variants having deletions of short binding epitopes. On the basis of these results, we propose a model in which AXIN1 competes with dishevelled (DVL) for CK1ϵ and regulates CK1ϵ-induced phosphorylation of DVL and activation of Wnt/β-catenin signaling.

• Klíčová slova
• Myc (c-Myc), Wnt pathway, axin, casein kinase 1ϵ, dishevelled, intrinsically disordered region, p53, peptide array, scaffold protein, serine/threonine protein kinase,
• MeSH
• axin protein metabolismus   MeSH
• beta-katenin metabolismus   MeSH
• čipová analýza proteinů metody   MeSH
• fosforylace MeSH
• interakční proteinové domény a motivy * MeSH
• kaseinkinasa Iepsilon metabolismus   MeSH
• kompetitivní vazba MeSH
• lidé MeSH
• peptidy metabolismus   MeSH
• protein dishevelled metabolismus   MeSH
• proteiny Wnt metabolismus   MeSH
• signální dráha Wnt MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• axin protein MeSH
• AXIN1 protein, human MeSH Prohlížeč
• beta-katenin MeSH
• kaseinkinasa Iepsilon MeSH
• peptidy MeSH
• protein dishevelled MeSH
• proteiny Wnt MeSH

Dishevelled-3 (Dvl3), a key component of the Wnt signaling pathways, acts downstream of Frizzled (Fzd) receptors and gets heavily phosphorylated in response to pathway activation by Wnt ligands. Casein kinase 1ϵ (CK1ϵ) was identified as the major kinase responsible for Wnt-induced Dvl3 phosphorylation. Currently it is not clear which Dvl residues are phosphorylated and what is the consequence of individual phosphorylation events. In the present study we employed mass spectrometry to analyze in a comprehensive way the phosphorylation of human Dvl3 induced by CK1ϵ. Our analysis revealed >50 phosphorylation sites on Dvl3; only a minority of these sites was found dynamically induced after co-expression of CK1ϵ, and surprisingly, phosphorylation of one cluster of modified residues was down-regulated. Dynamically phosphorylated sites were analyzed functionally. Mutations within PDZ domain (S280A and S311A) reduced the ability of Dvl3 to activate TCF/LEF (T-cell factor/lymphoid enhancer factor)-driven transcription and induce secondary axis in Xenopus embryos. In contrast, mutations of clustered Ser/Thr in the Dvl3 C terminus prevented ability of CK1ϵ to induce electrophoretic mobility shift of Dvl3 and its even subcellular localization. Surprisingly, mobility shift and subcellular localization changes induced by Fzd5, a Wnt receptor, were in all these mutants indistinguishable from wild type Dvl3. In summary, our data on the molecular level (i) support previous the assumption that CK1ϵ acts via phosphorylation of distinct residues as the activator as well as the shut-off signal of Wnt/β-catenin signaling and (ii) suggest that CK1ϵ acts on Dvl via different mechanism than Fzd5.

• Klíčová slova
• Casein Kinase 1ϵ, Cell Signaling, Dishevelled-3, Frizzled5, Mass Spectrometry (MS), Phosphorylation, Post-translational Modification (PTM), Wnt Pathway,
• MeSH
• adaptorové proteiny signální transdukční chemie   metabolismus   MeSH
• chromatografie kapalinová MeSH
• fosfoproteiny chemie   metabolismus   MeSH
• fosforylace MeSH
• frizzled receptory metabolismus   MeSH
• genetická transkripce MeSH
• HEK293 buňky MeSH
• kaseinkinasa Iepsilon metabolismus   MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• protein dishevelled MeSH
• proteiny Xenopus MeSH
• retardační test MeSH
• sbalování proteinů MeSH
• sekvence aminokyselin MeSH
• subcelulární frakce metabolismus   MeSH
• tandemová hmotnostní spektrometrie MeSH
• Xenopus laevis MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• DVL1 protein, Xenopus MeSH Prohlížeč
• DVL3 protein, human MeSH Prohlížeč
• fosfoproteiny MeSH
• frizzled receptory MeSH
• FZD5 protein, human MeSH Prohlížeč
• kaseinkinasa Iepsilon MeSH
• protein dishevelled MeSH
• proteiny Xenopus MeSH

Dishevelled (Dvl) is a key component in the Wnt/β-catenin signaling pathway. Dvl can multimerize to form dynamic protein aggregates, which are required for the activation of downstream signaling. Upon pathway activation by Wnts, Dvl becomes phosphorylated to yield phosphorylated and shifted (PS) Dvl. Both activation of Dvl in Wnt/β-catenin signaling and Wnt-induced PS-Dvl formation are dependent on casein kinase 1 (CK1) δ/ε activity. However, the overexpression of CK1 was shown to dissolve Dvl aggregates, and endogenous PS-Dvl forms irrespective of whether or not the activating Wnt triggers the Wnt/β-catenin pathway. Using a combination of gain-of-function, loss-of-function, and domain mapping approaches, we attempted to solve this discrepancy regarding the role of CK1ε in Dvl biology. We analyzed mutual interaction of CK1δ/ε and two other Dvl kinases, CK2 and PAR1, in the Wnt/β-catenin pathway. We show that CK2 acts as a constitutive kinase whose activity is required for the further action of CK1ε. Furthermore, we demonstrate that the two consequences of CK1ε phosphorylation are separated both spatially and functionally; first, CK1ε-mediated induction of TCF/LEF-driven transcription (associated with dynamic recruitment of Axin1) is mediated via a PDZ-proline-rich region of Dvl. Second, CK1ε-mediated formation of PS-Dvl is mediated by the Dvl3 C terminus. Furthermore, we demonstrate with several methods that PS-Dvl has decreased ability to polymerize with other Dvls and could, thus, act as the inactive signaling intermediate. We propose a multistep and multikinase model for Dvl activation in the Wnt/β-catenin pathway that uncovers a built-in de-activation mechanism that is triggered by activating phosphorylation of Dvl by CK1δ/ε.

• MeSH
• adaptorové proteiny signální transdukční genetika   metabolismus   MeSH
• beta-katenin genetika   metabolismus   MeSH
• fosfoproteiny genetika   metabolismus   MeSH
• fosforylace fyziologie   MeSH
• HEK293 buňky MeSH
• kaseinkinasa Idelta genetika   metabolismus   MeSH
• kaseinkinasa Iepsilon genetika   metabolismus   MeSH
• kaseinkinasa II genetika   metabolismus   MeSH
• lidé MeSH
• myši MeSH
• peptidové mapování MeSH
• protein dishevelled MeSH
• proteiny Wnt genetika   metabolismus   MeSH
• receptor PAR-1 genetika   metabolismus   MeSH
• signální transdukce fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• beta-katenin MeSH
• DVL3 protein, human MeSH Prohlížeč
• Dvl3 protein, mouse MeSH Prohlížeč
• fosfoproteiny MeSH
• kaseinkinasa Idelta MeSH
• kaseinkinasa Iepsilon MeSH
• kaseinkinasa II MeSH
• protein dishevelled MeSH
• proteiny Wnt MeSH
• receptor PAR-1 MeSH

INTRODUCTION: Breast cancer is one of the most common types of cancer in women. One of the genes that were found mutated in breast cancer is casein kinase 1 epsilon (CK1epsilon). Because CK1epsilon is a crucial regulator of the Wnt signaling cascades, we determined how these CK1epsilon mutations interfere with the Wnt pathway and affect the behavior of epithelial breast cancer cell lines. METHODS: We performed in silico modeling of various mutations and analyzed the kinase activity of the CK1epsilon mutants both in vitro and in vivo. Furthermore, we used reporter and small GTPase assays to identify how mutation of CK1epsilon affects different branches of the Wnt signaling pathway. Based on these results, we employed cell adhesion and cell migration assays in MCF7 cells to demonstrate a crucial role for CK1epsilon in these processes. RESULTS: In silico modeling and in vivo data showed that autophosphorylation at Thr 44, a site adjacent to the breast cancer point mutations in the N-terminal lobe of human CK1epsilon, is involved in positive regulation of the CK1epsilon activity. Our data further demonstrate that, in mammalian cells, mutated forms of CK1epsilon failed to affect the intracellular localization and phosphorylation of Dvl2; we were able to demonstrate that CK1epsilon mutants were unable to enhance Dvl-induced TCF/LEF-mediated transcription, that CK1epsilon mutants acted as loss-of-function in the Wnt/beta-catenin pathway, and that CK1epsilon mutants activated the noncanonical Wnt/Rac-1 and NFAT pathways, similar to pharmacological inhibitors of CK1. In line with these findings, inhibition of CK1 promoted cell migration as well as decreased cell adhesion and E-cadherin expression in the breast cancer-derived cell line MCF7. CONCLUSIONS: In summary, these data suggest that the mutations of CK1epsilon found in breast cancer can suppress Wnt/beta-catenin as well as promote the Wnt/Rac-1/JNK and Wnt/NFAT pathways, thus contributing to breast cancer development via effects on cell adhesion and migration. In terms of molecular mechanism, our data indicate that the breast cancer point mutations in the N-terminal lobe of CK1epsilon, which are correlated with decreased phosphorylation activities of mutated forms of CK1epsilon both in vitro and in vivo, interfere with positive autophosphorylation at Thr 44.

• MeSH
• beta-katenin metabolismus   MeSH
• buněčná adheze MeSH
• duktální karcinom prsu genetika   metabolismus   patologie   MeSH
• fosforylace MeSH
• imunoprecipitace MeSH
• kaseinkinasa Iepsilon chemie   genetika   metabolismus   MeSH
• konformace proteinů MeSH
• lidé MeSH
• MAP kinasa-kinasa 4 metabolismus   MeSH
• messenger RNA genetika   MeSH
• mutace genetika   MeSH
• nádorové buněčné linie MeSH
• nádory prsu genetika   metabolismus   patologie   MeSH
• pohyb buněk * MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• proliferace buněk MeSH
• proteiny Wnt metabolismus   MeSH
• rac1 protein vázající GTP metabolismus   MeSH
• transkripční faktory NFATC metabolismus   MeSH
• western blotting MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• beta-katenin MeSH
• kaseinkinasa Iepsilon MeSH
• MAP kinasa-kinasa 4 MeSH
• messenger RNA MeSH
• proteiny Wnt MeSH
• rac1 protein vázající GTP MeSH
• RAC1 protein, human MeSH Prohlížeč
• transkripční faktory NFATC MeSH