In higher metazoans, the nuclear hormone receptors activate transcription trough their specific adaptors, nuclear hormone receptor adaptors NCoA, which are absent in lower metazoans. The Nine amino acid TransActivation Domain, 9aaTAD, was reported for a large number of the transcription activators that recruit general mediators of transcription. In this study, we demonstrated that the 9aaTAD from NHR-49 receptor of nematode C.elegans activates transcription as a small peptide. We showed that the ancient 9aaTAD domains are conserved in the nuclear hormone receptors including human HNF4, RARa, VDR and PPARg. Also their small 9aaTAD peptides effectively activated transcription in absence of the NCoA adaptors. We also showed that adjacent H11 domains in ancient and modern hormone receptors have an inhibitory effect on their 9aaTAD function.

• Klíčová slova
• 9aaTAD, CBP, HNF4, KIX, MED15, PPAR, RARa, VDL,
• MeSH
• aktivace transkripce * MeSH
• alfa receptor kyseliny retinové chemie   metabolismus   MeSH
• Caenorhabditis elegans chemie   metabolismus   MeSH
• hepatocytární jaderný faktor 4 chemie   metabolismus   MeSH
• lidé MeSH
• molekulární modely MeSH
• peptidy chemie   metabolismus   MeSH
• PPAR gama chemie   metabolismus   MeSH
• proteinové domény MeSH
• proteiny Caenorhabditis elegans chemie   metabolismus   MeSH
• receptory cytoplazmatické a nukleární chemie   metabolismus   MeSH
• receptory kalcitriolu chemie   metabolismus   MeSH
• sekvence aminokyselin MeSH
• sekvenční seřazení MeSH
• signální transdukce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alfa receptor kyseliny retinové MeSH
• hepatocytární jaderný faktor 4 MeSH
• NHR-49 protein, C elegans MeSH Prohlížeč
• peptidy MeSH
• PPAR gama MeSH
• proteiny Caenorhabditis elegans MeSH
• RARA protein, human MeSH Prohlížeč
• receptory cytoplazmatické a nukleární MeSH
• receptory kalcitriolu MeSH
• VDR protein, human MeSH Prohlížeč

Trichoplax adhaerens, the only known species of Placozoa is likely to be closely related to an early metazoan that preceded branching of Cnidaria and Bilateria. This animal species is surprisingly well adapted to free life in the World Ocean inhabiting tidal costal zones of oceans and seas with warm to moderate temperatures and shallow waters. The genome of T. adhaerens (sp. Grell) includes four nuclear receptors, namely orthologue of RXR (NR2B), HNF4 (NR2A), COUP-TF (NR2F) and ERR (NR3B) that show a high degree of similarity with human orthologues. In the case of RXR, the sequence identity to human RXR alpha reaches 81% in the DNA binding domain and 70% in the ligand binding domain. We show that T. adhaerens RXR (TaRXR) binds 9-cis retinoic acid (9-cis-RA) with high affinity, as well as high specificity and that exposure of T. adhaerens to 9-cis-RA regulates the expression of the putative T. adhaerens orthologue of vertebrate L-malate-NADP+ oxidoreductase (EC 1.1.1.40) which in vertebrates is regulated by a heterodimer of RXR and thyroid hormone receptor. Treatment by 9-cis-RA alters the relative expression profile of T. adhaerens nuclear receptors, suggesting the existence of natural ligands. Keeping with this, algal food composition has a profound effect on T. adhaerens growth and appearance. We show that nanomolar concentrations of 9-cis-RA interfere with T. adhaerens growth response to specific algal food and causes growth arrest. Our results uncover an endocrine-like network of nuclear receptors sensitive to 9-cis-RA in T. adhaerens and support the existence of a ligand-sensitive network of nuclear receptors at the base of metazoan evolution.

• Klíčová slova
• 9-cis retinoic acid, COUP, ERR, Food, HNF4, Nuclear receptor, RXR, Trichoplax adhaerens,
• Publikační typ
• časopisecké články MeSH

• Klíčová slova
• Birthweight, Hepatocyte nuclear factor-4 alpha (HNF4A), Maturity-onset diabetes of the young (MODY), Penetrance,
• MeSH
• diabetes mellitus 2. typu * genetika   MeSH
• hepatocytární jaderný faktor 1-alfa genetika   MeSH
• hepatocytární jaderný faktor 4 genetika   MeSH
• kohortové studie MeSH
• lidé MeSH
• mutace MeSH
• penetrance MeSH
• porodní hmotnost genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• dopisy MeSH
• práce podpořená grantem MeSH
• Názvy látek
• hepatocytární jaderný faktor 1-alfa MeSH
• hepatocytární jaderný faktor 4 MeSH
• HNF4A protein, human MeSH Prohlížeč

HNF4A mutations cause increased birth weight, transient neonatal hypoglycemia, and maturity onset diabetes of the young (MODY). The most frequently reported HNF4A mutation is p.R114W (previously p.R127W), but functional studies have shown inconsistent results; there is a lack of cosegregation in some pedigrees and an unexpectedly high frequency in public variant databases. We confirm that p.R114W is a pathogenic mutation with an odds ratio of 30.4 (95% CI 9.79-125, P = 2 × 10(-21)) for diabetes in our MODY cohort compared with control subjects. p.R114W heterozygotes did not have the increased birth weight of patients with other HNF4A mutations (3,476 g vs. 4,147 g, P = 0.0004), and fewer patients responded to sulfonylurea treatment (48% vs. 73%, P = 0.038). p.R114W has reduced penetrance; only 54% of heterozygotes developed diabetes by age 30 years compared with 71% for other HNF4A mutations. We redefine p.R114W as a pathogenic mutation that causes a distinct clinical subtype of HNF4A MODY with reduced penetrance, reduced sensitivity to sulfonylurea treatment, and no effect on birth weight. This has implications for diabetes treatment, management of pregnancy, and predictive testing of at-risk relatives. The increasing availability of large-scale sequence data is likely to reveal similar examples of rare, low-penetrance MODY mutations.

• MeSH
• diabetes mellitus 2. typu farmakoterapie   genetika   MeSH
• dospělí MeSH
• genetická predispozice k nemoci genetika   MeSH
• haplotypy genetika   MeSH
• hepatocytární jaderný faktor 4 genetika   MeSH
• hypoglykemika terapeutické užití   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace genetika   MeSH
• odds ratio MeSH
• porodní hmotnost genetika   fyziologie   MeSH
• senioři MeSH
• sulfonylmočovinové sloučeniny terapeutické užití   MeSH
• výpočetní biologie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• hepatocytární jaderný faktor 4 MeSH
• hypoglykemika MeSH
• sulfonylmočovinové sloučeniny MeSH

Prediction methods have become an integral part of biomedical and biotechnological research. However, their clinical interpretations are largely based on biochemical or molecular data, but not clinical data. Here, we focus on improving the reliability and clinical applicability of prediction algorithms. We assembled and curated two large non-overlapping large databases of clinical phenotypes. These phenotypes were caused by missense variations in 44 and 63 genes associated with Mendelian diseases. We used these databases to establish and validate the model, allowing us to improve the predictions obtained from EVmutation, SNAP2 and PoPMuSiC 2.1. The predictions of clinical effects suffered from a lack of specificity, which appears to be the common constraint of all recently used prediction methods, although predictions mediated by these methods are associated with nearly absolute sensitivity. We introduced evidence-based tailoring of the default settings of the prediction methods; this tailoring substantially improved the prediction outcomes. Additionally, the comparisons of the clinically observed and theoretical variations led to the identification of large previously unreported pools of variations that were under negative selection during molecular evolution. The evolutionary variation analysis approach described here is the first to enable the highly specific identification of likely disease-causing missense variations that have not yet been associated with any clinical phenotype.

• MeSH
• algoritmy MeSH
• ektodysplasiny genetika   MeSH
• fenotyp MeSH
• genetická variace MeSH
• genetické nemoci vrozené genetika   MeSH
• genomika MeSH
• glukosa-6-fosfátdehydrogenasa genetika   MeSH
• hemoglobiny genetika   MeSH
• hepatocytární jaderný faktor 4 genetika   MeSH
• lidé MeSH
• missense mutace MeSH
• modely genetické * MeSH
• molekulární evoluce MeSH
• mutace * MeSH
• pravděpodobnostní funkce MeSH
• proteomika MeSH
• tyrosinfosfatasa nereceptorového typu 11 genetika   MeSH
• výpočetní biologie metody   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• EDA protein, human MeSH Prohlížeč
• ektodysplasiny MeSH
• G6PD protein, human MeSH Prohlížeč
• glukosa-6-fosfátdehydrogenasa MeSH
• hemoglobin B MeSH Prohlížeč
• hemoglobiny MeSH
• hepatocytární jaderný faktor 4 MeSH
• HNF4A protein, human MeSH Prohlížeč
• PTPN11 protein, human MeSH Prohlížeč
• tyrosinfosfatasa nereceptorového typu 11 MeSH

AIMS/HYPOTHESIS: MODY (Maturity Onset Diabetes of the Young) is an autosomal dominant inherited type of diabetes with significant genetic heterogeneity. New mutations causing MODY are still being found. A genetically confirmed diagnosis of MODY allows application of individualized treatment based on the underlying concrete genetic dysfunction. Detection of novel MODY mutations helps provide a more complete picture of the possible MODY genotypes. MATERIALS AND METHODS: We tested 43 adult Czech patients with clinical characteristics of MODY, using direct sequencing of HNF1A (hepatocyte nuclear factor 1-alpha), HNF4A (hepatocyte nuclear factor 4-alpha) and GCK (glucokinase) genes. RESULTS: In three Czech families we identified three novel mutations we believe causing MODY-two missense mutations in HNF1A [F268L (c.802T>C) and P291S (c.871C>T)] and one frame shift mutation in GCK V244fsdelG (c.729delG). Some of the novel HNF1A mutation carriers were successfully transferred from insulin to gliclazide, while some of the novel GCK mutation carriers had a good clinical response when switched from insulin or oral antidiabetic drugs to diet. CONCLUSION: We describe three novel MODY mutations in three Czech families. The identification of MODY mutations had a meaningful impact on therapy on the mutation carriers.

• MeSH
• diabetes mellitus farmakoterapie   genetika   MeSH
• dietoterapie MeSH
• fenotyp MeSH
• gliklazid terapeutické užití   MeSH
• glukokinasa genetika   MeSH
• hepatocytární jaderný faktor 1-alfa genetika   MeSH
• hepatocytární jaderný faktor 4 genetika   MeSH
• hypoglykemika MeSH
• inzulin terapeutické užití   MeSH
• lidé MeSH
• mutace * MeSH
• rodokmen MeSH
• výsledek terapie MeSH
• zdraví rodiny MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Československo MeSH
• Názvy látek
• gliklazid MeSH
• glukokinasa MeSH
• hepatocytární jaderný faktor 1-alfa MeSH
• hepatocytární jaderný faktor 4 MeSH
• hypoglykemika MeSH
• inzulin MeSH

Monogenic diabetes is a gateway to precision medicine through molecular mechanistic insight. Hepatocyte nuclear factor 1A (HNF-1A) and HNF-4A are transcription factors that engage in crossregulatory gene transcription networks to maintain glucose-stimulated insulin secretion in pancreatic β cells. Variants in the HNF1A and HNF4A genes are associated with maturity-onset diabetes of the young (MODY). Here, we explored 4 variants in the P2-HNF4A promoter region: 3 in the HNF-1A binding site and 1 close to the site, which were identified in 63 individuals from 21 families of different MODY disease registries across Europe. Our goal was to study the disease causality for these variants and to investigate diabetes mechanisms on the molecular level. We solved a crystal structure of HNF-1A bound to the P2-HNF4A promoter and established a set of techniques to probe HNF-1A binding and transcriptional activity toward different promoter variants. We used isothermal titration calorimetry, biolayer interferometry, x-ray crystallography, and transactivation assays, which revealed changes in HNF-1A binding or transcriptional activities for all 4 P2-HNF4A variants. Our results suggest distinct disease mechanisms of the promoter variants, which can be correlated with clinical phenotype, such as age of diagnosis of diabetes, and be important tools for clinical utility in precision medicine.

• Klíčová slova
• Diabetes, Metabolism, Structural biology, Transcription,
• MeSH
• diabetes mellitus 2. typu * genetika   metabolismus   MeSH
• hepatocytární jaderný faktor 1-alfa * genetika   metabolismus   MeSH
• hepatocytární jaderný faktor 4 * genetika   metabolismus   MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• promotorové oblasti (genetika) * genetika   MeSH
• regulace genové exprese MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hepatocytární jaderný faktor 1-alfa * MeSH
• hepatocytární jaderný faktor 4 * MeSH
• HNF1A protein, human MeSH Prohlížeč
• HNF4A protein, human MeSH Prohlížeč

Herbal medicines have been increasingly used in the last three decades. Despite their popularity, safety issues with herbal products need to be addressed. We performed a feasibility study of the toxic responses of human induced pluripotent stem cell-derived hepatocytes (iHep cells) to phytochemicals in comparison with hepatoblasoma-derived HepG2 cells and long-term human hepatocytes (LTHHs). The iHep cells expressed typical hepatocyte markers cytochrome P450 3A4 (CYP3A4), hepatocyte nuclear factor 4α, and albumin despite the expression of immature markers α-fetoprotein and cytokeratin 19. We studied the responses of iHep cells to phytochemicals saikosaponin D, triptolide, deoxycalyciphylline B, and monocrotaline with different mode of toxicity employing MTS and lactate dehydrogenase (LDH) assays. Saikosaponin D and triptolide caused dose-dependent cytotoxicity in the iHep cells, which were more sensitive than LTHHs and HepG2 cells. Saikosaponin D-induced cytotoxicity tightly correlated with increased LDH leakage in the iHep cells. Although deoxycalyciphylline B did not exhibit toxic effect on the iHep and HepG2 cells when compared with LTHHs, it decreased CYP3A7 expression in the iHep cells and increased CYP1A2 expression in HepG2 cells. We hereby show the feasibility of using iHep cells to detect toxic effects of phytochemicals.

• Klíčová slova
• CYP3A4, Herbal medicine, Human induced pluripotent stem cell, Phytochemical, Primary human hepatocyte,
• MeSH
• albuminy metabolismus   MeSH
• alfa-fetoproteiny metabolismus   MeSH
• dospělí MeSH
• fytonutrienty toxicita   MeSH
• hepatocytární jaderný faktor 4 metabolismus   MeSH
• hepatocyty účinky léků   metabolismus   MeSH
• indukované pluripotentní kmenové buňky cytologie   MeSH
• keratin-19 metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• mladiství MeSH
• studie proveditelnosti MeSH
• systém (enzymů) cytochromů P-450 metabolismus   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• albuminy MeSH
• alfa-fetoproteiny MeSH
• fytonutrienty MeSH
• hepatocytární jaderný faktor 4 MeSH
• HNF4A protein, human MeSH Prohlížeč
• keratin-19 MeSH
• KRT19 protein, human MeSH Prohlížeč
• systém (enzymů) cytochromů P-450 MeSH

Cylindrospermopsin (CYN) has been recognized as a potent waterborne hepatotoxin with an increasing environmental occurrence. However, CYN effects on the specific populations of hepatic cells involved in liver tissue development, renewal, and regeneration, have not been characterized yet. We used human embryonic stem cells to analyze the hepatic differentiation stage-specific effect of CYN. Our results strongly suggest that CYN might contribute to the development of chronic adverse outcomes by disrupting liver tissue homeostasis in terms of (1) cellular stress and damage induced in the mature differentiated hepatocytes, which was associated with a necrotic cell death and thus possibly also inflammatory responses; (2) selective elimination of HNF4α+ cells from populations of progenitor cells and immature hepatocytes during hepatic differentiation, which could possibly lead to an impaired liver renewal and regeneration; (3) impaired hepatic functions of immature hepatocytes, such as decreased albumin secretion or increased lipid accumulation, which could contribute to the development of liver steatosis; and (4) survival of the immature and AFP-expressing cells with the limited ability to further differentiate, which could represent a tumor-promoting condition.

• Klíčová slova
• cyanotoxin, cylindrospermopsin, hepatic differentiation, human embryonic stem cells, liver,
• MeSH
• albuminy metabolismus   MeSH
• alkaloidy MeSH
• apoptóza MeSH
• bakteriální toxiny toxicita   MeSH
• buněčná diferenciace účinky léků   MeSH
• hepatocytární jaderný faktor 4 metabolismus   MeSH
• hepatocyty účinky léků   MeSH
• játra účinky léků   MeSH
• kmenové buňky MeSH
• lidé MeSH
• lidské embryonální kmenové buňky MeSH
• metabolismus lipidů MeSH
• nekróza MeSH
• oxidační stres účinky léků   MeSH
• sinice MeSH
• sladká voda MeSH
• toxiny kmene Cyanobacteria MeSH
• uracil analogy a deriváty   toxicita   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• albuminy MeSH
• alkaloidy MeSH
• bakteriální toxiny MeSH
• cylindrospermopsin MeSH Prohlížeč
• hepatocytární jaderný faktor 4 MeSH
• HNF4A protein, human MeSH Prohlížeč
• toxiny kmene Cyanobacteria MeSH
• uracil MeSH

The organic cation transporter 1 (OCT1) is the dominant carrier of organic cationic drugs and some positively charged endogenous compounds into hepatocytes. OCT1 has unique expression pattern. It has the highest expression among drug transporters in normal human hepatocytes with large interindividual variability, but it has negligible expression in other tissues or their tumors. Nowadays, it is clear that the regulation of SLC22A1 gene encoding OCT1 transporter is rather complex and that transactivation with hepatocyte nuclear factor 4α (HNF4α) and CCAAT-enhancer-binding protein (C/EBPs) transcription factors as well as epigenetic regulation contribute to its unique hepatocyte-specific expression pattern. Unfortunately, species- and tissue-specific regulation of OCT1 and its orthologs as well as significant down-regulation in most immortalized cell lines hamper the study of SLC22A1 gene regulation. In the current review, we summarize our current understanding of human OCT1 transporter hepatic gene regulation and we propose potential post-transcriptional regulation by predicted miRNAs. We also discuss in detail recent findings on indirect regulation of the transporter via farnesoid X receptor (FXR), glucocorticoid receptor and pregnane X (PXR) receptor, which point out to potential novel mechanisms of xenobiotic-transporting and drug-metabolizing proteins regulation in the human liver as well as to potentially novel drug-drug interaction mechanisms. We also propose that comprehensive understanding of mechanisms of SLC22A1 gene regulation could direct research for other drug transporters and drug-metabolizing enzymes highly expressed in hepatocytes and controlled by HNF4α or other liver-enriched transcription factors.

• Klíčová slova
• Gene regulation, hepatic uptake, liver, nuclear receptors, organic cation transporter 1, transporter,
• MeSH
• epigeneze genetická MeSH
• hepatocytární jaderný faktor 4 metabolismus   MeSH
• hepatocyty metabolismus   MeSH
• lidé MeSH
• mikro RNA metabolismus   MeSH
• pregnanový X receptor MeSH
• přenašeč organických kationtů 1 metabolismus   MeSH
• proteiny vázající zesilovač transkripce CCAAT metabolismus   MeSH
• receptory cytoplazmatické a nukleární metabolismus   MeSH
• receptory glukokortikoidů metabolismus   MeSH
• regulace genové exprese * MeSH
• steroidní receptory metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• farnesoid X-activated receptor MeSH Prohlížeč
• hepatocytární jaderný faktor 4 MeSH
• mikro RNA MeSH
• pregnanový X receptor MeSH
• přenašeč organických kationtů 1 MeSH
• proteiny vázající zesilovač transkripce CCAAT MeSH
• receptory cytoplazmatické a nukleární MeSH
• receptory glukokortikoidů MeSH
• steroidní receptory MeSH