Lens induction is a classical developmental model allowing investigation of cell specification, spatiotemporal control of gene expression, as well as how transcription factors are integrated into highly complex gene regulatory networks (GRNs). Pax6 represents a key node in the gene regulatory network governing mammalian lens induction. Meis1 and Meis2 homeoproteins are considered as essential upstream regulators of Pax6 during lens morphogenesis based on their interaction with the ectoderm enhancer (EE) located upstream of Pax6 transcription start site. Despite this generally accepted regulatory pathway, Meis1-, Meis2- and EE-deficient mice have surprisingly mild eye phenotypes at placodal stage of lens development. Here, we show that simultaneous deletion of Meis1 and Meis2 in presumptive lens ectoderm results in arrested lens development in the pre-placodal stage, and neither lens placode nor lens is formed. We found that in the presumptive lens ectoderm of Meis1/Meis2 deficient embryos Pax6 expression is absent. We demonstrate using chromatin immunoprecipitation (ChIP) that in addition to EE, Meis homeoproteins bind to a remote, ultraconserved SIMO enhancer of Pax6. We further show, using in vivo gene reporter analyses, that the lens-specific activity of SIMO enhancer is dependent on the presence of three Meis binding sites, phylogenetically conserved from man to zebrafish. Genetic ablation of EE and SIMO enhancers demostrates their requirement for lens induction and uncovers an apparent redundancy at early stages of lens development. These findings identify a genetic requirement for Meis1 and Meis2 during the early steps of mammalian eye development. Moreover, they reveal an apparent robustness in the gene regulatory mechanism whereby two independent "shadow enhancers" maintain critical levels of a dosage-sensitive gene, Pax6, during lens induction.

• MeSH
• dánio pruhované genetika   MeSH
• ektoderm růst a vývoj   patologie   MeSH
• genové regulační sítě genetika   MeSH
• homeodoménové proteiny genetika   metabolismus   MeSH
• lidé MeSH
• myši MeSH
• nádorové proteiny genetika   metabolismus   MeSH
• oči růst a vývoj   metabolismus   patologie   MeSH
• oční čočka růst a vývoj   metabolismus   patologie   MeSH
• transkripční faktor Meis1 MeSH
• transkripční faktor PAX6 genetika   metabolismus   MeSH
• vazebná místa MeSH
• vývojová regulace genové exprese MeSH
• zesilovače transkripce genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• homeodoménové proteiny MeSH
• MEIS1 protein, human MeSH Prohlížeč
• Meis1 protein, mouse MeSH Prohlížeč
• Mrg1 protein, mouse MeSH Prohlížeč
• nádorové proteiny MeSH
• Pax6 protein, mouse MeSH Prohlížeč
• transkripční faktor Meis1 MeSH
• transkripční faktor PAX6 MeSH

The choroid plexus (ChP) produces cerebrospinal fluid and forms an essential brain barrier. ChP tissues form in each brain ventricle, each one adopting a distinct shape, but remarkably little is known about the mechanisms underlying ChP development. Here, we show that epithelial WNT5A is crucial for determining fourth ventricle (4V) ChP morphogenesis and size in mouse. Systemic Wnt5a knockout, or forced Wnt5a overexpression beginning at embryonic day 10.5, profoundly reduced ChP size and development. However, Wnt5a expression was enriched in Foxj1-positive epithelial cells of 4V ChP plexus, and its conditional deletion in these cells affected the branched, villous morphology of the 4V ChP. We found that WNT5A was enriched in epithelial cells localized to the distal tips of 4V ChP villi, where WNT5A acted locally to activate non-canonical WNT signaling via ROR1 and ROR2 receptors. During 4V ChP development, MEIS1 bound to the proximal Wnt5a promoter, and gain- and loss-of-function approaches demonstrated that MEIS1 regulated Wnt5a expression. Collectively, our findings demonstrate a dual function of WNT5A in ChP development and identify MEIS transcription factors as upstream regulators of Wnt5a in the 4V ChP epithelium.

• Klíčová slova
• Choroid plexus, Epithelium, Meis1, Meis2, Morphogenesis, WNT5a,
• MeSH
• buněčné linie MeSH
• CRISPR-Cas systémy genetika   MeSH
• čtvrtá mozková komora embryologie   MeSH
• epitel metabolismus   MeSH
• epitelové buňky metabolismus   MeSH
• HEK293 buňky MeSH
• lidé MeSH
• mozek embryologie   MeSH
• myši knockoutované MeSH
• myši MeSH
• plexus chorioideus embryologie   MeSH
• promotorové oblasti (genetika) genetika   MeSH
• protein Wnt 5a genetika   metabolismus   MeSH
• signální transdukce fyziologie   MeSH
• sirotčí receptory podobné receptoru tyrosinkinasy metabolismus   MeSH
• transkripční faktor Meis1 metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• Meis1 protein, mouse MeSH Prohlížeč
• protein Wnt 5a MeSH
• Ror1 protein, mouse MeSH Prohlížeč
• Ror2 protein, mouse MeSH Prohlížeč
• sirotčí receptory podobné receptoru tyrosinkinasy MeSH
• transkripční faktor Meis1 MeSH
• Wnt5a protein, mouse MeSH Prohlížeč

BACKGROUND: Restless legs syndrome (RLS) is associated with common variants in three intronic and intergenic regions in MEIS1, BTBD9, and MAP2K5/LBXCOR1 on chromosomes 2p, 6p and 15q. METHODS: Our study investigated these variants in 649 RLS patients and 1230 controls from the Czech Republic (290 cases and 450 controls), Austria (269 cases and 611 controls) and Finland (90 cases and 169 controls). Ten single nucleotide polymorphisms (SNPs) within the three genomic regions were selected according to the results of previous genome-wide scans. Samples were genotyped using Sequenom platforms. RESULTS: We replicated associations for all loci in the combined samples set (rs2300478 in MEIS1, p = 1.26 x 10(-5), odds ratio (OR) = 1.47, rs3923809 in BTBD9, p = 4.11 x 10(-5), OR = 1.58 and rs6494696 in MAP2K5/LBXCOR1, p = 0.04764, OR = 1.27). Analysing only familial cases against all controls, all three loci were significantly associated. Using sporadic cases only, we could confirm the association only with BTBD9. CONCLUSION: Our study shows that variants in these three loci confer consistent disease risks in patients of European descent. Among the known loci, BTBD9 seems to be the most consistent in its effect on RLS across populations and is also most independent of familial clustering.

• MeSH
• dospělí MeSH
• frekvence genu MeSH
• genetická predispozice k nemoci MeSH
• genotyp MeSH
• homeodoménové proteiny genetika   MeSH
• jednonukleotidový polymorfismus * MeSH
• korepresorové proteiny MeSH
• lidé středního věku MeSH
• lidé MeSH
• MAP kinasa-kinasa 5 genetika   MeSH
• nádorové proteiny genetika   MeSH
• odds ratio MeSH
• proteiny nervové tkáně MeSH
• represorové proteiny genetika   MeSH
• senioři MeSH
• syndrom neklidných nohou genetika   MeSH
• transkripční faktor Meis1 MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Finsko MeSH
• Rakousko MeSH
• Názvy látek
• BTBD9 protein, human MeSH Prohlížeč
• homeodoménové proteiny MeSH
• korepresorové proteiny MeSH
• MAP kinasa-kinasa 5 MeSH
• MAP2K5 protein, human MeSH Prohlížeč
• MEIS1 protein, human MeSH Prohlížeč
• nádorové proteiny MeSH
• proteiny nervové tkáně MeSH
• represorové proteiny MeSH
• SKOR1 protein, human MeSH Prohlížeč
• transkripční faktor Meis1 MeSH
• transkripční faktory MeSH

BACKGROUND: Meis family of transcription factors operates in Pbx-Meis-Hox regulatory network controlling development of various tissues including eye, limbs, heart, hindbrain or craniofacial skeletal elements originating from the neural crest. Although studies in mouse provide abundant information about Meis factors function in embryogenesis, little is known about their role in zebrafish. RESULTS: We generated zebrafish lines carrying null mutations in meis1a, meis1b, meis2a, and meis2b genes. Only meis1b mutants are lethal at larval stage around 13 dpf whereas the other mutant lines are viable and fertile. We focused on development of neural crest-derived craniofacial structures such as tendons, cranial nerves, cartilage and accompanying muscles. Meis1b mutants displayed morphogenetic abnormalities in the cartilage originating from the first and second pharyngeal arches. Meckel's cartilage was shorter and wider with fused anterior symphysis and abnormal chondrocyte organization. This resulted in impaired tendons and muscle fiber connections while tenocyte development was not largely affected. CONCLUSIONS: Loss-of-function mutation in meis1b affects cartilage morphology in the lower jaw that leads to disrupted organization of muscles and tendons.

• Klíčová slova
• Meis, chondrocyte differentiation, craniofacial development, muscle fiber, zebrafish,
• MeSH
• chrupavka embryologie   metabolismus   MeSH
• crista neuralis embryologie   metabolismus   MeSH
• dánio pruhované * embryologie   genetika   MeSH
• homeodoménové proteiny genetika   metabolismus   MeSH
• lebka embryologie   MeSH
• morfogeneze * genetika   MeSH
• proteiny dánia pruhovaného * genetika   metabolismus   MeSH
• transkripční faktor Meis1 * genetika   metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• homeodoménové proteiny MeSH
• proteiny dánia pruhovaného * MeSH
• transkripční faktor Meis1 * MeSH

BACKGROUND: Restless legs syndrome (RLS) is a frequent neurological disorder which is presented in idiopathic and secondary form. Idiopathic RLS is associated with common genetic variants in four chromosomal regions. Recently, multiple sclerosis (MS) was identified as a common cause for secondary RLS. The aim of our study was to evaluate the prevalence of RLS among Czech patients with MS and to further analyze the impact of known genetic risk factors for RLS in patients with MS. METHODS: Each patient underwent a semi-structured interview. A patient was considered to be affected by RLS if all four standard criteria had ever been met in their lifetime. The sample was genotyped using 12 single nucleotide polymorphisms within the four genomic regions, which were selected according to the results of previous genome-wide association studies. RESULTS: A total of 765 subjects with MS were included in the study and the diagnosis of RLS was confirmed in 245 subjects (32.1%, 95%CI 28.7-35.4%). The genetic association study included 642 subjects; 203 MS patients with RLS were compared to 438 MS patients without RLS. No significant association with MEIS 1, BTBD9, and PTPRD gene variants was found despite sufficient statistical power for the first two loci. There was a trend for association with the MAP2K5/SCOR1 gene - the best model for the risk allele was the recessive one (p nominal=0.0029, p corrected for four loci and two models=0.023, odds ratio=1.60). CONCLUSION: We confirmed that RLS prevalence was high in patients with multiple sclerosis, but this form did not share all genetic risk variants with idiopathic RLS.

• MeSH
• alely MeSH
• dospělí MeSH
• genotyp MeSH
• homeodoménové proteiny genetika   MeSH
• jednonukleotidový polymorfismus genetika   MeSH
• lidé MeSH
• nádorové proteiny genetika   MeSH
• prevalence MeSH
• proteiny nervové tkáně MeSH
• rizikové faktory MeSH
• rozhovory jako téma MeSH
• roztroušená skleróza komplikace   epidemiologie   genetika   MeSH
• syndrom neklidných nohou epidemiologie   etiologie   genetika   MeSH
• transkripční faktor Meis1 MeSH
• transkripční faktory genetika   MeSH
• tyrosinfosfatasy receptorového typu, třída 2 genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• BTBD9 protein, human MeSH Prohlížeč
• homeodoménové proteiny MeSH
• MEIS1 protein, human MeSH Prohlížeč
• nádorové proteiny MeSH
• proteiny nervové tkáně MeSH
• PTPRD protein, human MeSH Prohlížeč
• transkripční faktor Meis1 MeSH
• transkripční faktory MeSH
• tyrosinfosfatasy receptorového typu, třída 2 MeSH

In the current study, we report on the development of novel series of pyrazolo[3,4-b]pyridine derivatives (8a-u, 11a-n, and 14a,b) as potential anticancer agents. The prepared pyrazolo[3,4-b]pyridines have been screened for their antitumor activity in vitro at NCI-DTP. Thereafter, compound 8a was qualified by NCI for full panel five-dose assay to assess its GI50, TGI and LC50 values. Compound 8a showed broad-spectrum anti-proliferative activities over the whole NCI panel, with outstanding growth inhibition full panel GI50 (MG-MID) value equals 2.16 μM and subpanel GI50 (MG-MID) range: 1.92-2.86 μM. Furthermore, pyrazolo[3,4-b]pyridines 8a, 8e-h, 8o, 8u, 11a, 11e, 11h, 11l and 14a-b were assayed for their antiproliferative effect against a panel of leukemia cell lines (K562, MV4-11, CEM, RS4;11, ML-2 and KOPN-8) where they possessed moderate to excellent anti-leukemic activity. Moreover, pyrazolo[3,4-b]pyridines 8o, 8u, 14a and 14b were further explored for their effect on cell cycle on RS4;11 cells, in which they dose-dependently increased populations of cells in G2/M phases. Finally we analyzed the changes of selected proteins (HOXA9, MEIS1, PARP, BcL-2 and McL-1) related to cell death and viability in RS4;11 cells via Western blotting. Collectively, the obtained results suggested pyrazolo[3,4-b]pyridines 8o, 8u, 14a and 14b as promising lead molecules for further optimization to develop more potent and efficient anticancer candidates.

• Klíčová slova
• Anticancer agents, Cell cycle arrest, HOXA9 protein, MEIS1 protein, One-pot synthesis, Pyrazolopyridine,
• MeSH
• antitumorózní látky chemická syntéza   chemie   farmakologie   MeSH
• buněčný cyklus účinky léků   MeSH
• léky antitumorózní - screeningové testy MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buňky kultivované MeSH
• proliferace buněk účinky léků   MeSH
• pyrazoly chemická syntéza   chemie   farmakologie   MeSH
• pyridiny chemická syntéza   chemie   farmakologie   MeSH
• viabilita buněk účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antitumorózní látky MeSH
• pyrazolo(3,4-b)pyridine MeSH Prohlížeč
• pyrazoly MeSH
• pyridiny MeSH

The vertebrate eye is derived from the neuroepithelium, surface ectoderm, and extracellular mesenchyme. The neuroepithelium forms an optic cup in which the spatial separation of three domains is established, namely, the region of multipotent retinal progenitor cells (RPCs), the ciliary margin zone (CMZ)-which possesses both a neurogenic and nonneurogenic potential-and the optic disk (OD), the interface between the optic stalk and the neuroretina. Here, we show by genetic ablation in the developing optic cup that Meis1 and Meis2 homeobox genes function redundantly to maintain the retinal progenitor pool while they simultaneously suppress the expression of genes characteristic of CMZ and OD fates. Furthermore, we demonstrate that Meis transcription factors bind regulatory regions of RPC-, CMZ-, and OD-specific genes, thus providing a mechanistic insight into the Meis-dependent gene regulatory network. Our work uncovers the essential role of Meis1 and Meis2 as regulators of cell fate competence, which organize spatial territories in the vertebrate eye.

• Klíčová slova
• Meis, development, retina,
• MeSH
• buněčná diferenciace genetika   MeSH
• genový knockdown MeSH
• homeodoménové proteiny genetika   metabolismus   MeSH
• kmenové buňky cytologie   metabolismus   MeSH
• obratlovci MeSH
• retina cytologie   metabolismus   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• homeodoménové proteiny MeSH
• transkripční faktory MeSH

AIMS: The Cardiac Conduction System (CCS) is progressively specified during development by interactions among a discrete number of Transcriptions Factors that ensure its proper patterning and the emergence of its functional properties. Meis genes encode homeodomain transcription factors (TFs) with multiple roles in mammalian development. In humans, Meis genes associate with congenital cardiac malformations and alterations of cardiac electrical activity, however the basis for these alterations has not been established. Here we studied the role of Meis transcription factors in cardiomyocyte development and function during mouse development and adult life. METHODS AND RESULTS: We studied Meis1 and Meis2 conditional deletion mouse models that allowed cardiomyocyte-specific elimination of Meis function during development and inducible elimination of Meis function in cardiomyocytes of the adult CCS. We studied cardiac anatomy, contractility and conduction. We report that Meis factors are global regulators of cardiac conduction, with a predominant role in the CCS. While constitutive Meis deletion in cardiomyocytes led to congenital malformations of the arterial pole and atria, as well as defects in ventricular conduction, Meis elimination in cardiomyocytes of the adult CCS produced sinus node dysfunction and delayed atrio-ventricular conduction. Molecular analyses unraveled Meis-controlled molecular pathways associated with these defects. Finally, we studied in transgenic mice the activity of a Meis1 human enhancer related to an SNP associated by GWAS to PR elongation and found that the transgene drives expression in components of the atrio-ventricular conduction system. CONCLUSIONS: Our study identifies Meis TFs as essential regulators of the establishment of cardiac conduction function during development and its maintenance during adult life. In addition, we generated animal models and identified molecular alterations that will ease the study of Meis-associated conduction defects and congenital malformations in humans.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: TALE-class homeodomain transcription factors Meis and Pbx play important roles in formation of the embryonic brain, eye, heart, cartilage or hematopoiesis. Loss-of-function studies of Pbx1, 2 and 3 and Meis1 documented specific functions in embryogenesis, however, functional studies of Meis2 in mouse are still missing. We have generated a conditional allele of Meis2 in mice and shown that systemic inactivation of the Meis2 gene results in lethality by the embryonic day 14 that is accompanied with hemorrhaging. RESULTS: We show that neural crest cells express Meis2 and Meis2-defficient embryos display defects in tissues that are derived from the neural crest, such as an abnormal heart outflow tract with the persistent truncus arteriosus and abnormal cranial nerves. The importance of Meis2 for neural crest cells is further confirmed by means of conditional inactivation of Meis2 using crest-specific AP2α-IRES-Cre mouse. Conditional mutants display perturbed development of the craniofacial skeleton with severe anomalies in cranial bones and cartilages, heart and cranial nerve abnormalities. CONCLUSIONS: Meis2-null mice are embryonic lethal. Our results reveal a critical role of Meis2 during cranial and cardiac neural crest cells development in mouse.

• MeSH
• chrupavka abnormality   embryologie   MeSH
• crista neuralis embryologie   metabolismus   MeSH
• forkhead transkripční faktory biosyntéza   genetika   MeSH
• hlavové nervy embryologie   MeSH
• homeodoménové proteiny genetika   MeSH
• krvácení genetika   MeSH
• lebka embryologie   inervace   MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši MeSH
• represorové proteiny biosyntéza   genetika   MeSH
• srdce embryologie   MeSH
• transkripční faktor SOX9 biosyntéza   genetika   MeSH
• vrozené srdeční vady embryologie   genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• forkhead transkripční faktory MeSH
• Foxd3 protein, mouse MeSH Prohlížeč
• homeodoménové proteiny MeSH
• Mrg1 protein, mouse MeSH Prohlížeč
• represorové proteiny MeSH
• Sox9 protein, mouse MeSH Prohlížeč
• transkripční faktor SOX9 MeSH

UNLABELLED: In acute myeloid leukemia (AML), SWI/SNF chromatin remodeling complexes sustain leukemic identity by driving high levels of MYC. Previous studies have implicated the hematopoietic transcription factor PU.1 (SPI1) as an important target of SWI/SNF inhibition, but PU.1 is widely regarded to have pioneer-like activity. As a result, many questions have remained regarding the interplay between PU.1 and SWI/SNF in AML as well as normal hematopoiesis. Here we found that PU.1 binds to most of its targets in a SWI/SNF-independent manner and recruits SWI/SNF to promote accessibility for other AML core regulatory factors, including RUNX1, LMO2, and MEIS1. SWI/SNF inhibition in AML cells reduced DNA accessibility and binding of these factors at PU.1 sites and redistributed PU.1 to promoters. Analysis of nontumor hematopoietic cells revealed that similar effects also impair PU.1-dependent B-cell and monocyte populations. Nevertheless, SWI/SNF inhibition induced profound therapeutic response in an immunocompetent AML mouse model as well as in primary human AML samples. In vivo, SWI/SNF inhibition promoted leukemic differentiation and reduced the leukemic stem cell burden in bone marrow but also induced leukopenia. These results reveal a variable therapeutic window for SWI/SNF blockade in AML and highlight important off-tumor effects of such therapies in immunocompetent settings. SIGNIFICANCE: Disruption of PU.1-directed enhancer programs upon SWI/SNF inhibition causes differentiation of AML cells and induces leukopenia of PU.1-dependent B cells and monocytes, revealing the on- and off-tumor effects of SWI/SNF blockade.

• MeSH
• akutní myeloidní leukemie * farmakoterapie   genetika   metabolismus   MeSH
• buněčná diferenciace MeSH
• kostní dřeň patologie   MeSH
• leukopenie * genetika   MeSH
• lidé MeSH
• myši MeSH
• promotorové oblasti (genetika) MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH