Multistep phosphorelay (MSP) signaling integrates hormonal and environmental signals to control both plant development and adaptive responses. Type-A RESPONSE REGULATOR (RRA) genes, the downstream members of the MSP cascade and cytokinin primary response genes, are thought to mediate primarily the negative feedback regulation of (cytokinin-induced) MSP signaling. However, transcriptional data also suggest the involvement of RRA genes in stress-related responses. By employing evolutionary conservation with the well-characterized Arabidopsis thaliana RRA genes, we identified five and 38 novel putative RRA genes in Brassica oleracea and Brassica napus, respectively. Our phylogenetic analysis suggests the existence of gene-specific selective pressure, maintaining the homologs of ARR3, ARR6, and ARR16 as singletons during the evolution of Brassicaceae. We categorized RRA genes based on the kinetics of their cytokinin-mediated up-regulation and observed both similarities and specificities in this type of response across Brassicaceae species. Using bioinformatic analysis and experimental data demonstrating the cytokinin and abiotic stress responsiveness of the A. thaliana-derived TCSv2 reporter, we unveil the mechanistic conservation of cytokinin- and stress-mediated up-regulation of RRA genes in B. rapa and B. napus. Notably, we identify partial cytokinin dependency of cold stress-induced RRA transcription, thus further demonstrating the role of cytokinin signaling in crop adaptive responses.

• Klíčová slova
• Arabidopsis thaliana, Brassica napus, Brassica oleracea, Brassica rapa, cytokinins, multistep phosphorelay, osmotic stress, salinity, two-component signaling, type-A response regulator,
• MeSH
• Arabidopsis genetika   fyziologie   metabolismus   MeSH
• Brassica napus genetika   fyziologie   metabolismus   MeSH
• Brassica * genetika   fyziologie   metabolismus   MeSH
• cytokininy * metabolismus   MeSH
• fylogeneze MeSH
• fyziologický stres * MeSH
• regulace genové exprese u rostlin MeSH
• regulátory růstu rostlin metabolismus   MeSH
• rostlinné proteiny * genetika   metabolismus   MeSH
• signální transdukce MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokininy * MeSH
• regulátory růstu rostlin MeSH
• rostlinné proteiny * MeSH

Besides the long-standing role of cytokinins (CKs) as growth regulators, their current positioning at the interface of development and stress responses is coming into recognition. The current evidence suggests the notion that CKs are involved in heat stress response (HSR), however, the role of CK signaling components is still elusive. In this study, we have identified a role of the CK signaling components type-A Arabidopsis response regulators (ARRs) in HSR in Arabidopsis. The mutants of multiple type-A ARR genes exhibit improved basal and acquired thermotolerance and, altered response to oxidative stress in our physiological analyses. Through proteomics profiling, we show that the type-A arr mutants experience a 'stress-primed' state enabling them to respond more efficiently upon exposure to real stress stimuli. A substantial number of proteins that are involved in the heat-acclimatization process such as the proteins related to cellular redox status and heat shock, are already altered in the type-A arr mutants without a prior exposure to stress conditions. The metabolomics analyses further reveal that the mutants accumulate higher amounts of α-and γ-tocopherols, which are important antioxidants for protection against oxidative damage. Collectively, our results suggest that the type-A ARRs play an important role in heat stress response by affecting the redox homeostasis in Arabidopsis.

• Klíčová slova
• Arabidopsis response regulators, cytokinins, heat stress, heat-acclimatization, metabolomics, oxidative stress, proteomics,
• Publikační typ
• časopisecké články MeSH

Signal transduction pathways in both prokaryotes and eukaryotes utilize protein phosphorylation as a key regulatory mechanism. Recent studies have proven that eukaryotic-type serine/threonine protein kinases (Hank's type) are widespread in many bacteria, although little is known regarding the cellular processes they control. In this study, we have attempted to establish the role of a single eukaryotic-type protein kinase, StkP of Streptococcus pneumoniae, in bacterial survival. Our results indicate that the expression of StkP is important for the resistance of S. pneumoniae to various stress conditions. To investigate the impact of StkP on this phenotype, we compared the whole-genome expression profiles of the wild-type and DeltastkP mutant strains by microarray technology. This analysis revealed that StkP positively controls the transcription of a set of genes encoding functions involved in cell wall metabolism, pyrimidine biosynthesis, DNA repair, iron uptake, and oxidative stress response. Despite the reduced transformability of the stkP mutant, we found that the competence regulon was derepressed in the stkP mutant under conditions that normally repress natural competence development. Furthermore, the competence regulon was expressed independently of exogenous competence-stimulating peptide. In summary, our studies show that a eukaryotic-type serine/threonine protein kinase functions as a global regulator of gene expression in S. pneumoniae.

• MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• delece genu MeSH
• eukaryotické buňky enzymologie   MeSH
• fenotyp MeSH
• koncentrace vodíkových iontů MeSH
• mikrobiální viabilita účinky léků   genetika   MeSH
• mutace MeSH
• osmotický tlak MeSH
• oxidační stres MeSH
• peroxid vodíku farmakologie   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• protein-serin-threoninkinasy genetika   metabolismus   MeSH
• regulace genové exprese u bakterií * MeSH
• sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
• Streptococcus pneumoniae enzymologie   genetika   růst a vývoj   MeSH
• testy genetické komplementace MeSH
• vysoká teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• peroxid vodíku MeSH
• protein-serin-threoninkinasy MeSH

Fibroblast growth factor 21 (FGF21) is a novel metabolic regulator produced primarily by the liver that exerts potent antidiabetic and lipid-lowering effects in animal models of obesity and type 2 diabetes mellitus. This hormone contributes to body weight regulation and is strongly involved in the response to nutritional deprivation and ketogenic state in mice. The principal sites of metabolic actions of FGF21 are adipose tissue, liver and pancreas. Experimental studies have shown marked improvements in diabetes compensation and dyslipidemia after FGF21 administration in diabetic mice and primates. Positive metabolic actions of FGF21 without the presence of apparent side effects make this factor a hot candidate to treat type 2 diabetes and accompanying metabolic diseases. The aim of this review is to summarize the current knowledge about the metabolic effects of FGF21 including some preliminary data on changes of its levels in humans with a special emphasis on its therapeutic potential in type 2 diabetes mellitus.

• MeSH
• diabetes mellitus 2. typu farmakoterapie   metabolismus   MeSH
• energetický metabolismus účinky léků   MeSH
• fibroblastové růstové faktory škodlivé účinky   metabolismus   terapeutické užití   MeSH
• hypoglykemika škodlivé účinky   terapeutické užití   MeSH
• látky proti obezitě škodlivé účinky   terapeutické užití   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• obezita farmakoterapie   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• fibroblast growth factor 21 MeSH Prohlížeč
• fibroblastové růstové faktory MeSH
• hypoglykemika MeSH
• látky proti obezitě MeSH

Cytokinin has strong connections to development and a growing role in the abiotic stress response. Here we show that CYTOKININ RESPONSE FACTOR 2 (CRF2) is additionally involved in the salt (NaCl) stress response. CRF2 promoter-GUS expression indicates CRF2 involvement in the response to salt stress as well as the previously known cytokinin response. Interestingly, CRF2 mutant seedlings are quite similar to the wild type (WT) under non-stressed conditions yet have many distinct changes in response to salt stress. Cytokinin levels measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) that increased in the WT after salt stress are decreased in crf2, potentially from CRF2 regulation of cytokinin biosynthesis genes. Ion content measured by inductively coupled plasma optical emission spectrometry (ICP-OES) was increased in the WT for Na, K, Mn, Ca and Mg after salt stress, whereas the corresponding Ca and Mg increases are lacking in crf2. Many genes examined by RNA-seq analysis were altered transcriptionally by salt stress in both the WT and crf2, yet interestingly approximately one-third of salt-modified crf2 transcripts (2655) showed unique regulation. Different transcript profiles for salt stress in crf2 compared with the WT background was further supported through an examination of co-expressed genes by weighted gene correlation network analysis (WGCMA) and principal component analysis (PCA). Additionally, Gene Ontology (GO) enrichment terms found from salt-treated transcripts revealed most photosynthesis-related terms as only being affected in crf2, leading to an examination of chlorophyll levels and the efficiency of photosystem II (via the ratio of variable fluorescence to maximum fluorescence, Fv /Fm ) as well as physiology after salt treatment. Salt stress-treated crf2 plants had both reduced chlorophyll levels and lower Fv /Fm values compared with the WT, suggesting that CRF2 plays a role in the modulation of salt stress responses linked to photosynthesis.

• Klíčová slova
• Arabidopsis thaliana, CRF2, abiotic stress, cytokinin, cytokinin response factor, ionome, sodium, transcriptome,
• MeSH
• Arabidopsis * genetika   MeSH
• chlorofyl metabolismus   MeSH
• chromatografie kapalinová MeSH
• cytokininy metabolismus   MeSH
• fyziologický stres MeSH
• proteiny huseníčku * metabolismus   MeSH
• regulace genové exprese u rostlin MeSH
• solný stres MeSH
• tandemová hmotnostní spektrometrie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chlorofyl MeSH
• cytokininy MeSH
• proteiny huseníčku * MeSH

The silent information regulator 1 (Sirt1) has been shown to have negative effects on the Notch pathway in several contexts. We bring evidence that Sirt1 has a positive effect on Notch activation in Drosophila, in the context of sensory organ precursor specification and during wing development. The phenotype of Sirt1 mutant resembles weak Notch loss-of-function phenotypes, and genetic interactions of Sirt1 with the components of the Notch pathway also suggest a positive role for Sirt1 in Notch signalling. Sirt1 is necessary for the efficient activation of enhancer of split [E(spl)] genes by Notch in S2N cells. Additionally, the Notch-dependent response of several E(spl) genes is sensitive to metabolic stress caused by 2-deoxy-d-glucose treatment, in a Sirt1-dependent manner. We found Sirt1 associated with several proteins involved in Notch repression as well as activation, including the cofactor exchange factor Ebi (TBL1), the RLAF/LAF histone chaperone complex and the Tip60 acetylation complex. Moreover, Sirt1 participates in the deacetylation of the CSL transcription factor Suppressor of Hairless. The role of Sirt1 in Notch signalling is, therefore, more complex than previously recognized, and its diverse effects may be explained by a plethora of Sirt1 substrates involved in the regulation of Notch signalling.

• Klíčová slova
• Drosophila melanogaster, acetylation/deacetylation, metabolic regulation, notch signalling pathway, sirtuins,
• MeSH
• buněčné linie MeSH
• deoxyglukosa farmakologie   MeSH
• Drosophila MeSH
• hmotnostní spektrometrie MeSH
• imunoprecipitace MeSH
• messenger RNA antagonisté a inhibitory   MeSH
• proteiny Drosophily genetika   metabolismus   MeSH
• receptory Notch genetika   metabolismus   MeSH
• represorové proteiny genetika   metabolismus   MeSH
• RNA interference fyziologie   MeSH
• signální transdukce účinky léků   genetika   MeSH
• sirtuin 1 genetika   metabolismus   MeSH
• transkripční faktory bHLH genetika   metabolismus   MeSH
• vazba proteinů MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• deoxyglukosa MeSH
• E(spl)m7-HLH protein, Drosophila MeSH Prohlížeč
• messenger RNA MeSH
• proteiny Drosophily MeSH
• receptory Notch MeSH
• represorové proteiny MeSH
• sirtuin 1 MeSH
• transkripční faktory bHLH MeSH

BACKGROUND: The intake of meat, particularly processed meat, is a dietary risk factor for diabetes. Meat intake impairs insulin sensitivity and leads to increased oxidative stress. However, its effect on postprandial gastrointestinal hormone (GIH) secretion is unclear. We aimed to investigate the acute effects of two standardized isocaloric meals: a processed hamburger meat meal rich in protein and saturated fat (M-meal) and a vegan meal rich in carbohydrates (V-meal). We hypothesized that the meat meal would lead to abnormal postprandial increases in plasma lipids and oxidative stress markers and impaired GIH responses. METHODS: In a randomized crossover study, 50 patients suffering from type 2 diabetes (T2D) and 50 healthy subjects underwent two 3-h meal tolerance tests. For statistical analyses, repeated-measures ANOVA was performed. RESULTS: The M-meal resulted in a higher postprandial increase in lipids in both groups (p<0.001) and persistent postprandial hyperinsulinemia in patients with diabetes (p<0.001). The plasma glucose levels were significantly higher after the V-meal only at the peak level. The plasma concentrations of glucose-dependent insulinotropic peptide (GIP), peptide tyrosine-tyrosine (PYY) and pancreatic polypeptide (PP) were higher (p<0.05, p<0.001, p<0.001, respectively) and the ghrelin concentration was lower (p<0.001) after the M-meal in healthy subjects. In contrast, the concentrations of GIP, PYY and PP were significantly lower after the M-meal in T2D patients (p<0.001). Compared with the V-meal, the M-meal was associated with a larger increase in lipoperoxidation in T2D patients (p<0.05). CONCLUSION/INTERPRETATION: Our results suggest that the diet composition and the energy content, rather than the carbohydrate count, should be important considerations for dietary management and demonstrate that processed meat consumption is accompanied by impaired GIH responses and increased oxidative stress marker levels in diabetic patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT01572402.

• MeSH
• diabetes mellitus 2. typu krev   patologie   MeSH
• dieta veganská škodlivé účinky   MeSH
• gastrointestinální hormony krev   MeSH
• ghrelin krev   MeSH
• glukagonu podobný peptid 1 krev   MeSH
• inzulin krev   MeSH
• krevní glukóza MeSH
• lidé středního věku MeSH
• lidé MeSH
• lipidy krev   MeSH
• manipulace s potravinami MeSH
• maso škodlivé účinky   MeSH
• postprandiální období MeSH
• triglyceridy krev   MeSH
• žaludeční inhibiční polypeptid krev   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• gastrointestinální hormony MeSH
• ghrelin MeSH
• glukagonu podobný peptid 1 MeSH
• inzulin MeSH
• krevní glukóza MeSH
• lipidy MeSH
• triglyceridy MeSH
• žaludeční inhibiční polypeptid MeSH

Cultures of three-dimensional aggregates of embryonic stem cells (ESCs) called embryoid bodies (EBs) provide a valuable system for analyzing molecular mechanisms that regulate differentiation of this unique cell type. Cyclin-dependent kinase inhibitor p27Kip1 (p27) becomes elevated during the differentiation of mouse ESCs (mESCs). In this study, various aspects of differentiation of EBs produced from normal and p27-deficient mESCs were analyzed to address the biological significance of this elevation. It was found that EBs lacking p27 grew significantly bigger, but this was not accompanied by detect-able abnormalities in the activities of cyclin-dependent kinases (CDKs). In most EB cells, downregulation of activating cyclins rather than upregulation of inhibiting p27 is probably responsible for lowering the activity of their CDKs. Abnormalities in the development of specific cell lineages were also observed in p27-deficient EBs. These included elimination of cells positive for cytokeratin endo-A (TROMA-I) and increased proliferation and formation of cavities originating from cells positive for Lewis-X. Our data also suggest that although two different pools of Lewis-X-expressing cells, cluster forming (ESC-like) and cavity forming (neural progenitors), normally exist in EBs, the absence of p27 leads to the enhancement of only the neural pool. No failure was found when the neurogenic capacity of p27-deficient mESCs was tested using various protein markers. Together, our data point to a dual role of p27 in mESCs, with one role being in the regulation of proliferation and the other role in establishing some other aspects of a differentiated phenotype.

• MeSH
• antigen Lewis X metabolismus   MeSH
• buněčná diferenciace MeSH
• buněčný cyklus MeSH
• časové faktory MeSH
• down regulace MeSH
• embryo savčí fyziologie   MeSH
• fenotyp MeSH
• fluorescenční mikroskopie MeSH
• imunohistochemie MeSH
• imunoprecipitace MeSH
• inhibitor p27 cyklin-dependentní kinasy MeSH
• kmenové buňky metabolismus   MeSH
• kultivované buňky MeSH
• myši MeSH
• nádorové supresorové proteiny genetika   fyziologie   MeSH
• neurony metabolismus   MeSH
• proliferace buněk MeSH
• proteiny buněčného cyklu genetika   fyziologie   MeSH
• průtoková cytometrie MeSH
• upregulace MeSH
• viabilita buněk MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigen Lewis X MeSH
• Cdkn1b protein, mouse MeSH Prohlížeč
• inhibitor p27 cyklin-dependentní kinasy MeSH
• nádorové supresorové proteiny MeSH
• proteiny buněčného cyklu MeSH

We studied how deficiency in lamins A/C and lamina-associated polypeptide 2α (Lap2α) affects DNA repair after irradiation. A-type lamins and Lap2α were not recruited to local DNA lesions and did not accumulate to γ-irradiation-induced foci (IRIF), as it is generally observed for well-known marker of DNA lesions, 53BP1 protein. At micro-irradiated chromatin of lmna double knockout (dn) and Lap2α dn cells, 53BP1 protein levels were reduced, compared to locally irradiated wild-type counterpart. Decreased levels of 53BP1 we also observed in whole populations of lmna dn and Lap2α dn cells, irradiated by UV light. We also studied distribution pattern of 53BP1 protein in a genome outside micro-irradiated region. In Lap2α deficient cells, identical fluorescence of mCherry-tagged 53BP1 protein was found at both microirradiated region and surrounding chromatin. However, a well-known marker of double strand breaks, γH2AX, was highly abundant in the lesion-surrounding genome of Lap2α deficient cells. Described changes, induced by irradiation in Lap2α dn cells, were not accompanied by cell cycle changes. In Lap2α dn cells, we additionally performed analysis by FLIM (Fluorescence Lifetime Imaging Microscopy) that showed different dynamic behavior of mCherry-tagged 53BP1 protein pools when it was compared with wild-type (wt) fibroblasts. This analysis revealed three different fractions of mCherry-53BP1 protein. Two of them showed identical exponential decay times (τ1 and τ3), but the decay rate of τ2 and amplitudes of fluorescence decays (A1-A3) were statistically different in wt and Lap2α dn fibroblasts. Moreover, γ-irradiation weakened an interaction between A-type lamins and Lap2α. Together, our results demonstrate how depletion of Lap2α affects DNA damage response (DDR) and how chromatin compactness is changed in Lap2α deficient cells exposed to radiation.

• Klíčová slova
• DNA damage, Lap2α, confocal microscopy, epigenetics, immunohistochemistry, lamins,
• MeSH
• 53BP1 genetika   metabolismus   MeSH
• červený fluorescenční protein MeSH
• chromatin chemie   účinky záření   ultrastruktura   MeSH
• DNA vazebné proteiny nedostatek   genetika   MeSH
• embryo savčí MeSH
• fibroblasty cytologie   metabolismus   účinky záření   MeSH
• FRAP MeSH
• histony genetika   metabolismus   MeSH
• lamin typ A nedostatek   genetika   MeSH
• luminescentní proteiny genetika   metabolismus   MeSH
• membránové proteiny nedostatek   genetika   MeSH
• myši MeSH
• oprava DNA * MeSH
• poškození DNA MeSH
• regulace genové exprese MeSH
• rekombinantní fúzní proteiny genetika   metabolismus   MeSH
• reportérové geny MeSH
• signální transdukce MeSH
• transformované buněčné linie MeSH
• ultrafialové záření MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 53BP1 MeSH
• chromatin MeSH
• DNA vazebné proteiny MeSH
• gamma-H2AX protein, mouse MeSH Prohlížeč
• histony MeSH
• lamin typ A MeSH
• lamina-associated polypeptide 2 MeSH Prohlížeč
• luminescentní proteiny MeSH
• membránové proteiny MeSH
• rekombinantní fúzní proteiny MeSH
• Trp53bp1 protein, mouse MeSH Prohlížeč

T cells are pivotal in the adaptive immune defense, necessitating a delicate balance between robust response against infections and self-tolerance. Their activation involves intricate cross-talk among signaling pathways triggered by the T-cell antigen receptors (TCR) and co-stimulatory or inhibitory receptors. The molecular regulation of these complex signaling networks is still incompletely understood. Here, we identify the adaptor protein ABIN1 as a component of the signaling complexes of GITR and OX40 co-stimulation receptors. T cells lacking ABIN1 are hyper-responsive ex vivo, exhibit enhanced responses to cognate infections, and superior ability to induce experimental autoimmune diabetes in mice. ABIN1 negatively regulates p38 kinase activation and late NF-κB target genes. P38 is at least partially responsible for the upregulation of the key effector proteins IFNG and GZMB in ABIN1-deficient T cells after TCR stimulation. Our findings reveal the intricate role of ABIN1 in T-cell regulation.

• Klíčová slova
• ABIN1, Antigen Receptor, Co-stimulation, T Cells, p38,
• MeSH
• adaptorové proteiny signální transdukční * metabolismus   genetika   MeSH
• aktivace lymfocytů imunologie   genetika   MeSH
• cytotoxické T-lymfocyty * imunologie   metabolismus   MeSH
• diabetes mellitus 1. typu imunologie   genetika   metabolismus   MeSH
• glukokortikoidy indukovaný protein související s TNRF MeSH
• interferon gama metabolismus   MeSH
• lidé MeSH
• mitogenem aktivované proteinkinasy p38 metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši MeSH
• NF-kappa B metabolismus   MeSH
• receptory antigenů T-buněk metabolismus   MeSH
• receptory OX40 metabolismus   genetika   MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adaptorové proteiny signální transdukční * MeSH
• glukokortikoidy indukovaný protein související s TNRF MeSH
• interferon gama MeSH
• mitogenem aktivované proteinkinasy p38 MeSH
• NF-kappa B MeSH
• receptory antigenů T-buněk MeSH
• receptory OX40 MeSH
• Tnfrsf18 protein, mouse MeSH Prohlížeč