During development, the genome undergoes drastic reorganization within the nuclear space. To determine tridimensional genome folding, genome-wide techniques (damID/Hi-C) can be applied using cell populations, but these have to be calibrated using microscopy and single-cell analysis of gene positioning. Moreover, the dynamic behavior of chromatin has to be assessed on living samples. Combining fast stereotypic development with easy genetics and microscopy, the nematode C. elegans has become a model of choice in recent years to study changes in nuclear organization during cell fate acquisition. Here we present two complementary techniques to evaluate nuclear positioning of genes either by fluorescence in situ hybridization in fixed samples or in living worm embryos using the GFP-lacI/lacO chromatin-tagging system.

• MeSH
• analýza jednotlivých buněk MeSH
• Caenorhabditis elegans cytologie   genetika   MeSH
• chromatin metabolismus   MeSH
• genom genetika   MeSH
• hybridizace in situ fluorescenční metody   MeSH
• koncové značení zlomů DNA in situ metody   MeSH
• lac operon genetika   MeSH
• lac represory genetika   MeSH
• zelené fluorescenční proteiny genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chromatin MeSH
• lac represory MeSH
• zelené fluorescenční proteiny MeSH

AIMS: The aim of this study was to characterize ventricular activation patterns in normal and connexin40-deficient mice in order to dissect the role of connexin40 in developing the conduction system. METHODS AND RESULTS: We performed optical mapping of epicardial activation between ED9.5-18.5 and analysed ventricular activation patterns and times of left ventricular activation. Mouse embryos deficient for connexin40 were compared with normal and heterozygous littermates. Morphology of the primary interventricular ring (PIR) was delineated with the help of T3-LacZ transgene. Four major types of ventricular activation patterns characterized by primary breakthrough in different parts of the heart were detected during development: PIR, left ventricular apex, right ventricular apex, and dual right and left ventricular apices. Activation through PIR was frequently present at the early stages until ED12.5. From ED14.5, the majority of hearts showed dual left and right apical breakthrough, suggesting functionality of both bundle branches. Connexin40-deficient embryos showed initially a delay in left bundle branch function, but the right bundle branch block, previously described in the adults, was not detected in ED14.5 embryos and appeared only gradually with 80% penetrance at ED18.5. CONCLUSION: The switch of function from the early PIR conduction pathway to the mature apex to base activation is dependent upon upregulation of connexin40 expression in the ventricular trabeculae. The early function of right bundle branch does not depend on connexin40. Quantitative analysis of normal mouse embryonic ventricular conduction patterns will be useful for interpretation of effects of mutations affecting the function of the cardiac conduction system.

• MeSH
• akční potenciály MeSH
• blokáda Tawarova raménka genetika   metabolismus   MeSH
• gestační stáří MeSH
• Hisův svazek embryologie   metabolismus   MeSH
• konexiny nedostatek   genetika   MeSH
• lac operon MeSH
• morfogeneze MeSH
• myši knockoutované MeSH
• myši transgenní MeSH
• myši MeSH
• penetrance MeSH
• převodní systém srdeční embryologie   metabolismus   MeSH
• protein alfa 5 mezerového spoje MeSH
• srdeční komory embryologie   metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• zobrazování pomocí barviva citlivého na potenciál MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• konexiny MeSH

To elucidate the physiological meaning of OmpR-dependent expression of invasin gene (inv) inhibition in Yersinia enterocolitica, the function of the EnvZ/OmpR regulatory pathway in osmoregulation of inv expression was analyzed in detail. The osmoregulation of inv expression was found to be a multifaceted process involving both OmpR-dependent and -independent mechanisms. Analysis of inv transcription in strains lacking OmpR or EnvZ proteins indicated that kinase EnvZ is not the only regulator of OmpR phosphorylation. Using the transcriptional inv::lacZ fusion in a heterologous system (Escherichia coli) we tried to clarify the role of OmpR in the inv regulatory circuit composed of negative (H-NS) and positive (RovA) regulators of inv gene transcription. We were able to show a significant increase in inv expression in E. coli ompR background under H-NS( Ecoli )-repressed condition. Moreover, H-NS-mediated inv repression was relieved when RovA of Y. enterocolitica was expressed from a plasmid. Furthermore, we showed that RovA may activate inv expression irrespective on the presence of H-NS protein. Using this strategy we showed that OmpR of Y. enterocolitica decrease RovA-mediated inv activation.

• MeSH
• bakteriální adheziny genetika   MeSH
• bakteriální chromozomy genetika   MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• Escherichia coli genetika   metabolismus   MeSH
• fúze genů MeSH
• genetická transkripce MeSH
• lac operon genetika   MeSH
• osmolární koncentrace MeSH
• promotorové oblasti (genetika) MeSH
• regulace genové exprese u bakterií * MeSH
• trans-aktivátory genetika   metabolismus   MeSH
• Yersinia enterocolitica genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální adheziny MeSH
• bakteriální proteiny MeSH
• invasin, Yersinia MeSH Prohlížeč
• osmolarity response regulator proteins MeSH Prohlížeč
• trans-aktivátory MeSH

In this report, we describe the homing of hematopoietic stem cells (HSCs) to non-hematopoietic tissues in lethally irradiated (9Gy) hybrid mice transplanted intravenously with lin(-)/CD117(+) bone marrow cells from ROSA26 mice. The numbers of CFU-GM in spleen of irradiated transplanted mice were well above the levels found in non-irradiated group as early as day 8 after transplant. On 12th day regeneration of lymphocytes was observed, an increase in granulocytes was detected as late as on 33rd day. Transplanted cells containing lacZ gene were detected in recipient mice by histochemistry and their location in the thymus, liver, stomach and ileum was followed during 33days post-transplantation. On 8 and 33days post-transplantation, we found massive presence of donor (lacZ(+)) cells in the thymic cortex. Hematopoietic stem cell transplantation led not only to recovery of hematopoietic and lymphoid tissues but also facilitated recovery of the small intestinal mucosa, which was significantly damaged by ionizing radiation.

• MeSH
• časové faktory MeSH
• celotělové ozáření MeSH
• hematopoetické kmenové buňky fyziologie   MeSH
• hematopoetický systém fyziologie   MeSH
• lac operon MeSH
• lymfoidní tkáň fyziologie   MeSH
• myši MeSH
• pohyb buněk MeSH
• protoonkogenní proteiny c-kit * MeSH
• regenerace * MeSH
• střevní sliznice fyziologie   MeSH
• tenké střevo MeSH
• tkáňová distribuce MeSH
• transplantace hematopoetických kmenových buněk metody   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• protoonkogenní proteiny c-kit * MeSH

ER81, a member of the ETS family of transcription factors, is involved in processes of specification of neuronal identity, control of sensory-motor connectivity, and differentiation of muscle spindles. Spindles either degenerate or are abnormal in mutant mice lacking ER81. We examined whether ER81 is required for the development of another class of mechanoreceptors, the Pacinian corpuscle. ER81 was expressed by the inner core cells of the corpuscles, as reflected by expression of the lacZ reporter gene in Er81(+/lacZ) mutants, thereby suggesting a role for ER81 in the corpuscle development. No Pacinian corpuscles or their afferent nerve fibers were present in the crus of Er81 null mice at birth. Legs of mutant embryos examined at E16.5 were also devoid of the corpuscles, but not of their afferents. Thus, Pacinian corpuscles do not form, and their afferents do not survive, in the absence of ER81. A deficiency of dorsal root ganglia neurons expressing calretinin, a marker for neurons subserving Pacinian corpuscles, correlated with the absence of corpuscles and their afferents in Er81 null mice. These observations indicate a requirement for ER81 in the assembly of Pacinian corpuscles and the survival of the sensory neurons that innervate them.

• MeSH
• biologické markery metabolismus   MeSH
• delece genu MeSH
• DNA vazebné proteiny nedostatek   genetika   fyziologie   MeSH
• imunohistochemie MeSH
• kalbindin 2 MeSH
• lac operon MeSH
• myši knockoutované MeSH
• myši MeSH
• neurony aferentní cytologie   metabolismus   MeSH
• reportérové geny MeSH
• S100 kalcium vázající protein G metabolismus   MeSH
• spinální ganglia cytologie   MeSH
• transkripční faktory nedostatek   genetika   fyziologie   MeSH
• Vater-Paciniho tělíska růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• biologické markery MeSH
• Calb2 protein, mouse MeSH Prohlížeč
• DNA vazebné proteiny MeSH
• Etv1 protein, mouse MeSH Prohlížeč
• kalbindin 2 MeSH
• S100 kalcium vázající protein G MeSH
• transkripční faktory MeSH

In Paracoccus denitrificans at least three fumarate and nitrate reductase regulator (FNR)-like proteins [FnrP, nitrite and nitric oxide reductases regulator (NNR) and NarR] control the expression of several genes necessary for denitrifying growth. To gain more insight into this regulation, beta-galactosidase activity from a plasmid carrying the lacZ gene fused to the Escherichia coli melR promoter with the consensus FNR-binding (FF) site was examined. Strains defective in the fnrP gene produced only very low levels of beta-galactosidase, indicating that FnrP is the principal activator of the FF promoter. Anoxic beta-galactosidase levels were much higher relative to those under oxic growth and were strongly dependent on the nitrogen electron acceptor used, maximal activity being promoted by N(2)O. Additions of nitrate or nitroprusside lowered beta-galactosidase expression resulting from an oxic to micro-oxic switch. These results suggest that the activity of FnrP is influenced not only by oxygen, but also by other factors, most notably by NO concentration. Observations of nitric oxide reductase (NOR) activity in a nitrite-reductase-deficient strain and in cells treated with haemoglobin provided evidence for dual regulation of the synthesis of this enzyme, partly independent of NO. Both regulatory modes were operative in the FnrP-deficient strain, but not in the NNR-deficient strain, suggesting involvement of the NNR protein. This conclusion was further substantiated by comparing the respective NOR promoter activities.

• MeSH
• bakteriální geny MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• beta-galaktosidasa genetika   MeSH
• DNA vazebné proteiny genetika   metabolismus   MeSH
• kyslík metabolismus   MeSH
• lac operon MeSH
• mutace MeSH
• nitroprusid farmakologie   MeSH
• oxid dusnatý metabolismus   MeSH
• oxidoreduktasy metabolismus   MeSH
• Paracoccus denitrificans účinky léků   genetika   metabolismus   MeSH
• promotorové oblasti (genetika) MeSH
• regulace genové exprese enzymů účinky léků   MeSH
• regulace genové exprese u bakterií účinky léků   MeSH
• reportérové geny MeSH
• trans-aktivátory genetika   metabolismus   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• beta-galaktosidasa MeSH
• DNA vazebné proteiny MeSH
• FnrP protein, Paracoccus denitrificans MeSH Prohlížeč
• kyslík MeSH
• nitric-oxide reductase MeSH Prohlížeč
• nitroprusid MeSH
• NNR protein, Paracoccus denitrificans MeSH Prohlížeč
• oxid dusnatý MeSH
• oxidoreduktasy MeSH
• trans-aktivátory MeSH
• transkripční faktory MeSH

To test the effects of combined transduction of a suicide gene and genes coding for various immunostimulatory factors on the oncogenicity and immunogenicity of TC-1 cells (HPV-16 transformed C57BL/6 mouse cells), several bicistronic recombinant adeno-associated viruses (rAAV) were constructed. Each of these constructs carried, and in infected cells expressed, the herpes simplex type 1 thymidine-kinase gene (HSV-TK) and the gene of one of the following immunostimulatory factors: human monocyte chemoattractant protein 1 (MCP-1), mouse B7.1 costimulatory molecule (B7.1), or mouse granulocyte-macrophage colony-stimulating factor (GM-CSF). For control purposes, an rAAV carrying the HSV-TK gene and neomycin resistance gene (neo) and an rAAV containing the lacZ gene were used. All of these constructs proved functional both in mouse TC-1 and human 293T cells. For experiments in mice, TC-1 cells were infected in vitro with the AAV recombinants at an input multiplicity of 50 particles/cell; these cells were then administered to 5-week-old mice. As from day 5, half of the animals were given ganciclovir (GCV) (2.5 mg/day) for 10 days. With a single exception, none of the mice inoculated with cells treated with rAAV expressing HSV-TK + B7.1 or HSV-TK + MCP-1 developed tumour irrespective of GCV treatment. The tumour suppressive effect was less marked in animals inoculated with TC-1 cells infected with rAAV expressing HSV-TK + GM-CSF, and among these it was somewhat more pronounced in GCV-untreated animals. A clear antitumour effect of GCV treatment was only observed in mice inoculated with TC-1 cells transduced with rAAV expressing HSV-TK but no immunostimulatory factor. Mice that remained tumour-free on day 54 were challenged with untreated TC-1 cells. The tumour resistance rates found were related not only to the immunostimulatory gene used for the transduction, but also to GCV treatment. The best protection was recorded in mice pre-inoculated with TC-1 cells transduced with either B7.1 or MCP-1-expressing rAAV and not given GCV.

• MeSH
• antigeny CD80 genetika   MeSH
• antivirové látky terapeutické užití   MeSH
• chemokin CCL2 genetika   MeSH
• defektní viry genetika   MeSH
• Dependovirus genetika   MeSH
• faktor stimulující granulocyto-makrofágové kolonie genetika   MeSH
• ganciklovir terapeutické užití   MeSH
• genetická terapie * MeSH
• genetické vektory genetika   terapeutické užití   MeSH
• HeLa buňky MeSH
• imunoterapie metody   MeSH
• lac operon MeSH
• ledviny MeSH
• lidé MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buněčné linie transplantace   MeSH
• onkogenní proteiny virové fyziologie   MeSH
• Papillomaviridae fyziologie   MeSH
• Papillomavirus E7 - proteiny MeSH
• represorové proteiny * MeSH
• Simplexvirus enzymologie   genetika   MeSH
• thymidinkináza antagonisté a inhibitory   genetika   MeSH
• transdukce genetická MeSH
• transformované buněčné linie MeSH
• transplantace nádorů MeSH
• virová transformace buněk * MeSH
• xenogenní modely - testy antitumorózní aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD80 MeSH
• antivirové látky MeSH
• chemokin CCL2 MeSH
• E6 protein, Human papillomavirus type 16 MeSH Prohlížeč
• faktor stimulující granulocyto-makrofágové kolonie MeSH
• ganciklovir MeSH
• oncogene protein E7, Human papillomavirus type 16 MeSH Prohlížeč
• onkogenní proteiny virové MeSH
• Papillomavirus E7 - proteiny MeSH
• represorové proteiny * MeSH
• thymidinkináza MeSH

The effect of mutations in dnaK and dnaJ genes on the expression of two operons that are part of cysteine regulon was determined using Escherichia coli strains harboring cysPTWA::lacZ and cysJIH::lacZ fusions. Null dnaJ and dnaKdnaJ mutants were impaired in beta-galactosidase expression from both fusions. Efficient complementation of this defect by wild-type alleles present on a low-copy number plasmid was achieved. The presence of the pMH224 plasmid coding for CysB* protein defective in DNA binding lowered beta-galactosidase expression from cysPTWA::lacZ fusion strain harboring wild-type dnaKdnaJ alleles but did not diminish enzyme expression in delta dnaJ and delta dnaKdnaJ strains.

• MeSH
• alely MeSH
• bakteriální geny * MeSH
• beta-galaktosidasa genetika   MeSH
• cystein genetika   MeSH
• Escherichia coli enzymologie   genetika   MeSH
• exprese genu MeSH
• lac operon MeSH
• mutace MeSH
• operon MeSH
• plazmidy genetika   MeSH
• proteiny tepelného šoku HSP40 MeSH
• proteiny tepelného šoku HSP70 genetika   MeSH
• proteiny tepelného šoku genetika   MeSH
• proteiny z Escherichia coli * MeSH
• testy genetické komplementace MeSH
• umělá fúze genů MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• beta-galaktosidasa MeSH
• cystein MeSH
• DnaJ protein, E coli MeSH Prohlížeč
• dnaK protein, E coli MeSH Prohlížeč
• proteiny tepelného šoku HSP40 MeSH
• proteiny tepelného šoku HSP70 MeSH
• proteiny tepelného šoku MeSH
• proteiny z Escherichia coli * MeSH

PURPOSE: To calculate the probability of radiation-induced frank strand breakage (FSB) at each nucleotide in the Escherichia coli lac repressor-lac operator system using a simulation procedure. To compare calculated and experimental results. To asses the contribution of DNA conformational changes and of the masking by the protein to DNA protection by the repressor. MATERIALS AND METHODS: Two structures of the complex were extracted from the PDB databank: crystallography- and NMR-based structures. Calculations were made of the accessibility of the atoms mainly involved in strand breakage (H4' and H5') to O&Hdot; and of the FSB probabilities, along: (1) DNA in the complex; (2) DNA in the complex depleted of the repressor; and (3) a linear DNA having the same sequence. An 80bp fragment bearing the operator was irradiated alone or in presence of the repressor. The relative probabilities of FSB at each nucleotide were determined using sequencing gel electrophoresis. RESULTS: Calculations predict modulation of the accessibility of H4' and H5' atoms and of the probabilities of FSB along the DNA fragments of complexes. This is due to the protein-induced conformational change and to masking by bound protein. The best agreement with the experimental FSB was observed for calculations that use the crystallography-based structure. CONCLUSIONS: For specific DNA-protein complexes, our calculations can predict the protein radiolytic footprints on DNA. They show the significant contribution of the protein-induced DNA conformational change to DNA protection.

• MeSH
• bakteriální proteiny chemie   účinky záření   MeSH
• DNA bakterií chemie   genetika   účinky záření   MeSH
• Escherichia coli genetika   účinky záření   MeSH
• hydroxylový radikál chemie   účinky záření   MeSH
• konformace nukleové kyseliny MeSH
• konformace proteinů MeSH
• lac operon účinky záření   MeSH
• lac represory MeSH
• makromolekulární látky MeSH
• metoda Monte Carlo MeSH
• molekulární modely MeSH
• operátorové oblasti (genetika) účinky záření   MeSH
• poškození DNA MeSH
• proteiny z Escherichia coli * MeSH
• represorové proteiny chemie   účinky záření   MeSH
• sekvence nukleotidů MeSH
• tolerance záření MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• DNA bakterií MeSH
• hydroxylový radikál MeSH
• lac represory MeSH
• LacI protein, E coli MeSH Prohlížeč
• makromolekulární látky MeSH
• proteiny z Escherichia coli * MeSH
• represorové proteiny MeSH

The partition region qsopAB of the Coxiella burnetii plasmid QpH1 was analyzed. Locus qsopA alone appears to fulfill the partitioning function; QsopA represses its own promoter 17-fold. Two partition-associated incompatibility sites were identified: incA in a 200-bp region covering the qsopA promoter and incB in the qsopB locus.

• MeSH
• bakteriální proteiny genetika   MeSH
• Coxiella burnetii genetika   MeSH
• DNA bakterií genetika   MeSH
• lac operon MeSH
• operon MeSH
• plazmidy genetika   MeSH
• promotorové oblasti (genetika) MeSH
• regulace genové exprese u bakterií MeSH
• reportérové geny MeSH
• trans-aktivátory genetika   MeSH
• vazebná místa genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, U.S. Gov't, P.H.S. MeSH
• Názvy látek
• bakteriální proteiny MeSH
• DNA bakterií MeSH
• QsopA protein, Coxiella burnetii MeSH Prohlížeč
• QsopB protein, Coxiella burnetii MeSH Prohlížeč
• trans-aktivátory MeSH