BACKGROUND: The processes of fertilization and egg activation are vital for early embryogenesis. However, while the mechanisms associated with key events during these processes differ among species and modes of spawning, the signal pathways underlying these processes are opaque for many fishes, including economically important species. RESULTS: We investigated phenotypic traits, ultrastructure and protein expression levels in the eggs of the topmouth culter (Culter alburnus), a protected and economically important freshwater fish that exhibits two spawning modes, producing semi-buoyant eggs and adhesive eggs. Unfertilized eggs of C. alburnus were examined, as well as eggs at fertilization and 30 min post fertilization. Our results showed that in semi-buoyant eggs, energy metabolism was activated at fertilization, followed by elevated protein expression of cytoskeleton and extracellular matrix (ECM)-receptor interactions that resulted in rapid egg swelling; a recognized adaptation for lotic habitats. In contrast, in adhesive eggs fertilization initiated the process of sperm-egg fusion and blocking of polyspermy, followed by enhanced protein expression of lipid metabolism and the formation of egg envelope adhesion and hardening, which are adaptive in lentic habitats. CONCLUSION: Our findings indicate that alternative signal pathways differ between modes of spawning and timing during the key processes of fertilization and egg activation, providing new insights into the molecular mechanisms involved in adaptive early embryonic development in teleost fishes.

• Klíčová slova
• Egg activation, Fertilization, Signal pathway, Spawning mode, Teleost,
• MeSH
• fertilizace * MeSH
• ovum MeSH
• ryby MeSH
• signální transdukce MeSH
• sperma * MeSH
• spermie fyziologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Signal transducer and activator of transcription 3 (STAT3) is phosphorylated by various kinases, several of which have been implicated in aberrant fibroblast activation in fibrotic diseases including systemic sclerosis (SSc). Here we show that profibrotic signals converge on STAT3 and that STAT3 may be an important molecular checkpoint for tissue fibrosis. STAT3 signaling is hyperactivated in SSc in a TGFβ-dependent manner. Expression profiling and functional studies in vitro and in vivo demonstrate that STAT3 activation is mediated by the combined action of JAK, SRC, c-ABL, and JNK kinases. STAT3-deficient fibroblasts are less sensitive to the pro-fibrotic effects of TGFβ. Fibroblast-specific knockout of STAT3, or its pharmacological inhibition, ameliorate skin fibrosis in experimental mouse models. STAT3 thus integrates several profibrotic signals and might be a core mediator of fibrosis. Considering that several STAT3 inhibitors are currently tested in clinical trials, STAT3 might be a candidate for molecular targeted therapies of SSc.

• MeSH
• aktivace enzymů MeSH
• benzensulfonáty chemie   MeSH
• biopsie MeSH
• bleomycin chemie   MeSH
• dospělí MeSH
• fibroblasty metabolismus   MeSH
• fibróza metabolismus   MeSH
• fosforylace MeSH
• kolagen chemie   MeSH
• konfokální mikroskopie MeSH
• kůže metabolismus   MeSH
• kyseliny aminosalicylové chemie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• myši MeSH
• receptory transformujícího růstového faktoru beta metabolismus   MeSH
• senioři MeSH
• signální transdukce fyziologie   MeSH
• systémová sklerodermie metabolismus   MeSH
• transformující růstový faktor beta metabolismus   MeSH
• transkripční faktor STAT3 metabolismus   MeSH
• zánět MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• myši MeSH
• senioři MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• benzensulfonáty MeSH
• bleomycin MeSH
• kolagen MeSH
• kyseliny aminosalicylové MeSH
• NSC 74859 MeSH Prohlížeč
• receptory transformujícího růstového faktoru beta MeSH
• STAT3 protein, human MeSH Prohlížeč
• Stat3 protein, mouse MeSH Prohlížeč
• transformující růstový faktor beta MeSH
• transkripční faktor STAT3 MeSH

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

The expression of activated p38 mitogen-activated protein kinase (MAPK) and activated MAPK transcription factors c-jun, c-myc and elk-1 were examined in rat cerebellum after soman poisoning to determine the pathogenetic mechanism of the non-specific long-term effects of nerve agents. Male Wistar rats were poisoned by intramuscular administration of soman at a dose 60 microg kg(-1) (70% LD(50)) and samples were taken 1, 7 and 14 days after poisoning, immunohistochemically stained and p-p38MAPK, p-c-jun, p-c-myc and p-elk-1 expressions were measured using image analysis. Control groups were administered with saline instead of soman. The expression of activated p38MAPK and c-myc increased 14 days after soman poisoning while c-jun and elk-1 expressions remained unchanged 1, 7 and 14 days after soman poisoning. Delayed activation of p38 MAPK and its targets might be involved in the pathogenetic mechanism of the long-term neurophysiological toxic effects of nerve agents.

• MeSH
• aktivace enzymů účinky léků   MeSH
• chemické bojové látky otrava   MeSH
• cytoplazmatická granula účinky léků   enzymologie   MeSH
• imunohistochemie MeSH
• krysa rodu Rattus MeSH
• mitogenem aktivované proteinkinasy p38 metabolismus   MeSH
• mitogenem aktivované proteinkinasy metabolismus   MeSH
• mozeček cytologie   účinky léků   enzymologie   MeSH
• neurony účinky léků   enzymologie   MeSH
• počítačové zpracování obrazu MeSH
• potkani Wistar MeSH
• protoonkogenní proteiny c-jun metabolismus   MeSH
• protoonkogenní proteiny c-myc metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• soman otrava   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chemické bojové látky MeSH
• mitogenem aktivované proteinkinasy p38 MeSH
• mitogenem aktivované proteinkinasy MeSH
• protoonkogenní proteiny c-jun MeSH
• protoonkogenní proteiny c-myc MeSH
• soman MeSH

Cyanobacterial toxin cylindrospermopsin (CYN) is an emerging freshwater contaminant, whose expanding environmental occurrence might result into increased human health risks. CYN is potent hepatotoxin, with cytotoxicity and genotoxicity documented in primary hepatocytes or hepatoma cell lines. However, there is only limited information about CYN effects on adult human liver stem cells (LSCs), which play an important role in liver tissue development, regeneration and repair. In our study with human liver cell line HL1-hT1 which expresses characteristics of LSCs, CYN was found to be cytotoxic and increasing cell death after 24-48 h exposure to concentrations >1 μM. Subcytotoxic 1 μM concentration did not induce cell death or membrane damage, but inhibited cellular processes related to energy production, leading to a growth stagnation after >72 h. Interestingly, these effects were not associated with increased DNA damage, reactive oxygen species production, or endoplasmic reticulum stress. However, CYN induced a sustained (24-48 h) activation of mitogen-activated protein kinases ERK1/2 and p38, and increased expression of stress-related transcription factor ATF3. Thus, LSCs were not primarily affected by CYN-induced genotoxicity and oxidative stress, but via activation of signaling and transcriptional pathways critical for regulation of cell proliferation, stress responses, cell survival and inflammation. Alterations of LSCs during CYN-induced liver injury, including the role of nongenotoxic mechanisms, should be therefore considered in mechanistic assessments of chronic CYN hepatotoxicity and hepatocarcinogenicity.

• Klíčová slova
• Adult human liver stem cells HL1-hT1, Cylindrospermopsin, DNA damage, Mitogen-activated protein kinases, Nongenotoxic mechanisms, Oxidative stress,
• MeSH
• alkaloidy MeSH
• bakteriální toxiny toxicita   MeSH
• buněčné linie MeSH
• hepatocyty účinky léků   MeSH
• játra metabolismus   MeSH
• kmenové buňky MeSH
• lidé MeSH
• MAP kinasový signální systém MeSH
• mikrocystiny MeSH
• mitogenem aktivovaná proteinkinasa 1 metabolismus   MeSH
• mitogenem aktivovaná proteinkinasa 3 metabolismus   MeSH
• mitogenem aktivované proteinkinasy p38 metabolismus   MeSH
• mořské toxiny MeSH
• oxidační stres účinky léků   MeSH
• poškození DNA MeSH
• proliferace buněk MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• testy toxicity 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
• Názvy látek
• alkaloidy MeSH
• bakteriální toxiny MeSH
• cylindrospermopsin MeSH Prohlížeč
• MAPK1 protein, human MeSH Prohlížeč
• mikrocystiny MeSH
• mitogenem aktivovaná proteinkinasa 1 MeSH
• mitogenem aktivovaná proteinkinasa 3 MeSH
• mitogenem aktivované proteinkinasy p38 MeSH
• mořské toxiny MeSH
• reaktivní formy kyslíku MeSH
• toxiny kmene Cyanobacteria MeSH
• uracil MeSH

Dishevelled (DVL) proteins are key mediators of most Wnt pathways. In all vertebrates, three DVL paralogs are present (DVL1, DVL2 and DVL3) but it is poorly defined to what extent they are functionally redundant. Here, we generated T-REx HEK 293 cells with only one DVL paralog (i.e., DVL1-only, DVL2-only, and DVL3-only) and compared their response to Wnt-3a and Wnt-5a ligands with wild type and DVL triple knockout cells. We show that DVL is essential, in addition to the previously shown Wnt-3a-induced phosphorylation of LRP6 and transcriptional activation of TCF/LEF-dependent reporter, also for Wnt-3a-induced degradation of AXIN1 and Wnt-5a-induced phosphorylation of ROR1. We have quantified the molar ratios of DVL1:DVL2:DVL3 in our model to be approximately 4:80:16. Interestingly, DVL-only cells do not compensate for the lack of other paralogs and are still fully functional in all analyzed readouts with the exception of Wnt-3a-induced transcription assessed by TopFlash assay. In this assay, the DVL1-only cell line was the most potent; on the contrary, the DVL3-only cell line exhibited only the negligible capacity to mediate Wnt signals. Using a novel model system - complementation assays in T-REx HEK 293 with amplified Wnt signal response (RNF43/ZNRF3/DVL1/DVL2/DVL3 penta KO cells) we demonstrate that it is not the total amount of DVL but ratio of individual paralogs what decides the signal strength. In sum, this study contributes to our better understanding of the role of individual human DVL paralogs in the Wnt pathway.

• Klíčová slova
• Axin1, CRISPR/Cas9, Dishevelled 1/2/3, ROR1, Wnt signalling,
• MeSH
• aktivace transkripce MeSH
• fosfoproteiny * metabolismus   MeSH
• fosforylace MeSH
• HEK293 buňky MeSH
• lidé MeSH
• protein dishevelled metabolismus   MeSH
• signální dráha Wnt * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fosfoproteiny * MeSH
• protein dishevelled MeSH

Francisella tularensis is a facultative intracellular, gram-negative bacterium that induces apoptosis in macrophages and B cells. Here we show apoptotic pathways that are activated in the Ramos human B cell line in the course of F. tularensis infection. Live bacteria F. tularensis FSC200 activate caspases 8, 9 and 3, as well as Bid; release cytochrome c and apoptosis-inducing factor from mitochondria; and induce depolarization of mitochondrial membrane potential in the Ramos cell line, thus leading these cells to apoptosis. Unlike live bacteria, killed F. tularensis FSC200 bacteria activated only caspase 3, and did not cause apoptosis of Ramos cells as measured by annexin V. Killed bacteria also caused accumulation of anti-apoptotic protein Bclx(L) in mitochondrial membranes. Thus, live F. tularensis activates both caspase pathways (receptor-mediated and intrinsic) as well as caspase-independent mitochondrial death.

• MeSH
• apoptóza * MeSH
• B-lymfocyty mikrobiologie   MeSH
• buněčné linie MeSH
• cytochromy c metabolismus   MeSH
• Francisella tularensis patogenita   MeSH
• kaspasa 3 biosyntéza   MeSH
• kaspasa 8 biosyntéza   MeSH
• kaspasa 9 biosyntéza   MeSH
• lidé MeSH
• membránový potenciál mitochondrií MeSH
• mitochondrie enzymologie   fyziologie   MeSH
• protein Bid biosyntéza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• BID protein, human MeSH Prohlížeč
• CASP8 protein, human MeSH Prohlížeč
• cytochromy c MeSH
• kaspasa 3 MeSH
• kaspasa 8 MeSH
• kaspasa 9 MeSH
• protein Bid MeSH

Ten E. coli K1 strains isolated from the urine of children with urinary tract infections were sensitive to the bactericidal action of normal human serum (NHS). The role of the particular mechanisms of complement activation was determined in the process of killing these strains, showing variable sensitivity to the bactericidal action of NHS; three mechanisms of activation of human complement were observed. Important role of alternative pathway activation in the bactericidal action of NHS against E. coli K1 strains independent of the classical and lectin pathways was not established.

• MeSH
• aktivace komplementu * MeSH
• alternativní dráha komplementu MeSH
• antigeny bakteriální imunologie   MeSH
• antigeny povrchové imunologie   MeSH
• baktericidní aktivita krve MeSH
• dítě MeSH
• Escherichia coli imunologie   izolace a purifikace   MeSH
• infekce močového ústrojí mikrobiologie   MeSH
• infekce vyvolané Escherichia coli mikrobiologie   MeSH
• klasická dráha komplementu MeSH
• lektinová dráha komplementu imunologie   MeSH
• lidé MeSH
• mikrobiální viabilita MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny bakteriální MeSH
• antigeny povrchové MeSH

The innate immune cells sense microbial infection and self-ligands by pathogen recognition receptors (PRRs), such as toll-like receptors (TLRs) and regulatory receptors (RRs), associated with immunoreceptor tyrosine-based activation motif (ITAM). Rapid activation and concerted action of PRRs signaling and feedback inhibitory mechanisms must be engaged to ensure the host defense functions and to prevent cytotoxicity associated with excessive activation. ITAM-associated RRs can generate stimulatory or, paradoxically, inhibitory signals. The network of ITAM-associated RR, together with TLR-signaling pathways, are responsible for immunogenic or tolerogenic responses of macrophages and dendritic cells to their microenvironment. In macrophages, TLR4 signaling is inhibited by low-avidity ligation of ITAM-associated receptors, while high-avidity ligation of ITAM-associated receptors results in potentiation of TLR4 signaling together with resistance to extracellular cytokine microenvironment signals. In contrast to macrophages, TLR7/9 signaling in plasmacytoid DCs (pDCs) is inhibited by high-avidity ligation of ITAM-associated RR, while low-avidity ligation does not show any effect. Surprisingly, interference of ITAM-associated receptor signaling with TLR pathways has not been reported in conventional dendritic cells. Here, we present an overview of molecular mechanisms acting at the crossroads of TLR and ITAM-signaling pathways and address the question of how the high-avidity engagement of the ITAM-associated receptors in pDCs inhibits TLR7/9 signaling. Cellular context and spatiotemporal engagement of ITAM- and TLR-signaling pathways are responsible for different outcomes of macrophage versus pDC activation. While the cross-regulation of cytokine and TLR signaling, together with antigen presentation, are the principal functions of ITAM-associated RR in macrophages, the major role of these receptors in pDCs seems to be related to inhibition of cytokine production and reestablishment of a tolerogenic state following pDC activation. Pharmacologic targeting of TLR and ITAM signaling could be an attractive new therapeutic approach for treatment of chronic infections, cancer, and autoimmune and inflammatory diseases related to pDCs.

• Klíčová slova
• B cell receptor-like signaling, conventional dendritic cells, immunoreceptor tyrosine-based activation motif-associated receptor, macrophage, plasmacytoid dendritic cell, regulatory receptors, toll-like receptors,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Despite the reported cytotoxicity and apoptosis-inducing properties of sulforaphane (SF) in colon cancer cells, the details concerning individual mechanisms and signaling cascades underlying SF-mediated apoptosis remain unclear. To understand different aspects of SF-induced proapoptic signaling in advanced colon carcinoma, we investigated its mechanisms in metastatic SW620 cell line. Our results indicate that in SW620 cells SF acts to induce multivariate cascades including DNA-damage response pathway whose proapoptotic signaling is nevertheless reduced owing to the mutant status of p53 and caspase-2-JNK pathway which seems to complement and enhance p53-dependent signaling, however only in wild-type p53. Furthermore, both pathways require the active role of mitochondria and do not depend on generation of ROS, making SF an attractive chemopreventive agent whose antitumor properties should be further investigated in colon cancer.

• MeSH
• antikarcinogenní látky farmakologie   MeSH
• apoptóza účinky léků   MeSH
• cytochromy c metabolismus   MeSH
• isothiokyanatany MeSH
• JNK mitogenem aktivované proteinkinasy metabolismus   MeSH
• kaspasa 2 metabolismus   MeSH
• lidé MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• nádorové buněčné linie MeSH
• nádorový supresorový protein p53 metabolismus   MeSH
• nádory tračníku farmakoterapie   metabolismus   patologie   MeSH
• oxidační stres účinky léků   MeSH
• poškození DNA MeSH
• screeningové testy protinádorových léčiv MeSH
• sulfoxidy MeSH
• thiokyanatany farmakologie   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antikarcinogenní látky MeSH
• cytochromy c MeSH
• isothiokyanatany MeSH
• JNK mitogenem aktivované proteinkinasy MeSH
• kaspasa 2 MeSH
• nádorový supresorový protein p53 MeSH
• sulforaphane MeSH Prohlížeč
• sulfoxidy MeSH
• thiokyanatany MeSH