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Data on the structure of G-quadruplexes, noncanonical nucleic acid forms, supporting an idea of their potential participation in regulation of gene expression in response to the change in intracellular Na+i/K+i ratio are considered in the review. Structural variety of G-quadruplexes, role of monovalent cations in formation of this structure, and thermodynamic stability of G-quadruplexes are described. Data on the methods of their identification in the cells and biological functions of these structures are presented. Analysis of information about specific interactions of G-quadruplexes with some proteins was conducted, and their potential participation in the development of some pathological conditions, in particular, cancer and neurodegenerative diseases, is considered. Special attention is given to the plausible role of G-quadruplexes as sensors of intracellular Na+i/K+i ratio, because alteration of this parameter affects folding of G-quadruplexes changing their stability and, thereby, organization of the regulatory elements of nucleic acids. The data presented in the conclusion section demonstrate significant change in the expression of some early response genes under certain physiological conditions of cells and tissues depending on the intracellular Na+i/K+i ratio. [ABSTRACT FROM AUTHOR]

Stress is a major precipitating factor for psychiatric disorders and its effects may depend on its duration and intensity. Of note, there are differences in individual susceptibility to stress, with some subjects displaying vulnerability and others showing resistance. Furthermore, the ability to react to stressful-life events can alter the response to a subsequent new stressor. Hence, we investigated whether the vulnerability and resilience to the chronic mild stress (CMS) paradigm, in terms of the hedonic phenotype, are paralleled by a different response when facing a novel acute challenge. Specifically, rats submitted to CMS were stratified based on their sucrose intake into vulnerable (anhedonic rats showing reduce intake of sucrose) and resilient (rats not showing the anhedonic-like behavior) subgroups and then further exposed to an acute restraint stress (ARS). Then, neuronal activation was investigated by measuring the gene expression of early immediate (IEG) genes such as Arc and Cfos and early response (ERG) genes, such as Gadd45β, Sgk1, Dusp1, and Nr4a1, in brain regions that play a crucial role in the stress response. We found that resilient rats preserve the ability to increase ERG expression following the ARS selectively in the ventral hippocampus. Conversely, such ability is lost in vulnerable rats. Interestingly, the recovery from the anhedonic phenotype observed in vulnerable rats after 3 weeks of rest from the CMS procedure also parallels the restoration of the ability to adequately respond to the challenge. In conclusion, these findings support the role of the ventral subregion of the hippocampus in the management of both chronic and acute stress response and point to this brain subregion as a critical target for a potential therapeutic strategy aimed at promoting stress resilience. [ABSTRACT FROM AUTHOR]

Abstract Background Lung airway epithelial cells are part of innate immunity and the frontline of defense against bacterial infections. During infection, airway epithelial cells secrete proinflammatory mediators that participate in the recruitment of immune cells. Virulence factors expressed by bacterial pathogens can alter epithelial cell gene expression and modulate this response. Pseudomonas aeruginosa, a Gram-negative opportunistic pathogen, expresses numerous virulence factors to facilitate establishment of infection and evade the host immune response. This study focused on identifying the role of two major P. aeruginosa virulence factors, type III (T3SS) and type VI (T6SS) secretion systems, on the early transcriptome response of airway epithelial cells in vitro. Results We performed RNA-seq analysis of the transcriptome response of type II pneumocytes during infection with P. aeruginosa in vitro. We observed that P. aeruginosa differentially upregulates immediate-early response genes and transcription factors that induce proinflammatory responses in type II pneumocytes. P. aeruginosa infection of type II pneumocytes was characterized by up-regulation of proinflammatory networks, including MAPK, TNF, and IL-17 signaling pathways. We also identified early response genes and proinflammatory signaling pathways whose expression change in response to infection with P. aeruginosa T3SS and T6SS mutants in type II pneumocytes. We determined that T3SS and T6SS modulate the expression of EGR1, FOS, and numerous genes that are involved in proinflammatory responses in epithelial cells during infection. T3SS and T6SS were associated with two distinct transcriptomic signatures related to the activation of transcription factors such as AP1, STAT1, and SP1, and the secretion of pro-inflammatory cytokines such as IL-6 and IL-8. Conclusions Taken together, transcriptomic analysis of epithelial cells indicates that the expression of immediate-early response genes quickly changes upon infection with P. aeruginosa and this response varies depending on bacterial viability and injectosomes. These data shed light on how P. aeruginosa modulates host epithelial transcriptome response during infection using T3SS and T6SS.

Background: Lung airway epithelial cells are part of innate immunity and the frontline of defense against bacterial infections. During infection, airway epithelial cells secrete proinflammatory mediators that participate in the recruitment of immune cells. Virulence factors expressed by bacterial pathogens can alter epithelial cell gene expression and modulate this response. Pseudomonas aeruginosa, a Gram-negative opportunistic pathogen, expresses numerous virulence factors to facilitate establishment of infection and evade the host immune response. This study focused on identifying the role of two major P. aeruginosa virulence factors, type III (T3SS) and type VI (T6SS) secretion systems, on the early transcriptome response of airway epithelial cells in vitro. Results: We performed RNA-seq analysis of the transcriptome response of type II pneumocytes during infection with P. aeruginosa in vitro. We observed that P. aeruginosa differentially upregulates immediate-early response genes and transcription factors that induce proinflammatory responses in type II pneumocytes. P. aeruginosa infection of type II pneumocytes was characterized by up-regulation of proinflammatory networks, including MAPK, TNF, and IL-17 signaling pathways. We also identified early response genes and proinflammatory signaling pathways whose expression change in response to infection with P. aeruginosa T3SS and T6SS mutants in type II pneumocytes. We determined that T3SS and T6SS modulate the expression of EGR1, FOS, and numerous genes that are involved in proinflammatory responses in epithelial cells during infection. T3SS and T6SS were associated with two distinct transcriptomic signatures related to the activation of transcription factors such as AP1, STAT1, and SP1, and the secretion of pro-inflammatory cytokines such as IL-6 and IL-8. Conclusions: Taken together, transcriptomic analysis of epithelial cells indicates that the expression of immediate-early response genes quickly changes upon infection with P. aeruginosa and this response varies depending on bacterial viability and injectosomes. These data shed light on how P. aeruginosa modulates host epithelial transcriptome response during infection using T3SS and T6SS. [ABSTRACT FROM AUTHOR]

Abstract To develop a new antiviral preparation from a microbial source, the halophilic bacterium Bacillus pumilus E303035 was isolated from a soil sample collected at Qarhan Salt Lake in Qinghai, China. The inhibitory activity of an ethyl acetate extract of its fermentation broth was higher than that of an n-butanol extract. After isolation and purification, 9 compounds were obtained: cyclo(L-Leu-L-Pro) (1), cyclo(L-Pro-L-Tyr) (2), Brevianamide F (3), 2-(3-Indolyl) ethanol (4), N-[2-(1H-indol-3-yl) ethyl] acetamide (5), 3, 3-di(1H-indol-3-yl)propane-1,2-diol (6), Lincomycin B (7), dibutylphthalate (8), and p-hydroxyphenethyl alcohol (9). Compounds 1, 5, and 9 showed inhibitory activities against potato virus Y (PVY). Compounds 1, 4, and 9 had significant inhibitory activity against genes HC-pro, P3, and Nib, compound 5 against gene P3, and compounds 1 and 4 against NIa. Compounds 1, 4, 5, and 9 had significant inhibitory activity against genes VPg and 6K1. Active compounds 1, 5, and 9 had various effects on the expression of viral genes related to pathogenesis. Expression of genes cullin and XTH was up-regulated and CP was down-regulated, compared to the positive control. In conclusion, compounds 1, 5, and 9 might be considered as potential antiviral agents for future development.

The rapid progress of single-cell RNA-sequencing (scRNA-seq) at large scales has led to what seemed impossible until recently: the generation of comprehensive transcriptional maps of nearly all cells in multicellular tissues. We pinpoint three key elements as being critical to the production of these maps: scalability, spatial information, and accuracy of the transcriptome of the individual cells. Here, we discuss the ramifications of traditional cell-isolation protocols when capturing the transcriptional signature of cells as they exist in their native tissue context, the methods that have been developed to avoid these distortions, and the biological processes that have unraveled on account of these upgraded methodological approaches. Accuracy of single-cell transcriptomes is a key challenge for the construction of second-generation atlases. Standard cell dissociation methods induce strong transcriptional modifications in the majority of cell types. The main determinant of these changes is dissociation time, not cell type or tissue of origin. As a consequence, a large number of published single-cell atlases across tissues and biological set-ups are contaminated by cell dissociation-induced artefacts. A number of methods have been developed that moderate the dissociation-induced artefacts. Implementing (and optimizing) these methods widely will have a major impact towards a more accurate representation of cell states as they exist in their native tissue context. [ABSTRACT FROM AUTHOR]

Neurotrophin receptors regulate neuronal survival and network formation, as well as synaptic plasticity in the brain via interaction with their ligands. Here, we examined early changes in the expression of neurotrophin receptor genes Ntk1 (TrkA), Ntrk2 (TrkB), Ntrk3 (TrkC), Ngfr (p75NTR) and miRNAs that target theses gens in the mouse brain after induction of seizure activity by pentylenetetrazol. We found that expression of Ntrk3 and Ngfr was upregulated in the cortex and the hippocampus 1-3 hours after the seizures, while Ntrk2 expression increased after 3-6 hours in the anterior cortex and after 1 and 6 hours in the hippocampus. At the same time, the ratio of Bcl-2/Bax signaling proteins increased in the anterior and posterior cortex, but not in the hippocampus, suggesting the activation of anti-apoptotic signaling. Expression of miRNA-9 and miRNA-29a, which were predicted to target Ntrk3, was upregulated in the hippocampus 3 hours after pentylenetetrazol injection. Therefore, early cellular response to seizures in the brain includes induction of the Ntrk2, Ntrk3, Ngfr, miRNA-9, and miRNA-29a expression, as well as activation of Bcl-2 and Bax signaling pathways, which may characterize them as important mediators of neuronal adaptation and survival upon induction of the generalized brain activity. [ABSTRACT FROM AUTHOR]

Background/Aims: Prolonged hyperosmotic shrinkage evokes expression of osmoprotective genes via nuclear factor NFAT5-mediated pathway and activates Na+ influx via hypertonicity-induced cation channels (HICC). In human umbilical vein endothelial cells (HUVEC) elevation of intracellular sodium concentration ([Na+]i) triggers transcription of dozens of early response genes (ERG). This study examined the role of monovalent cations in the expression of Na+i-sensitive ERGs in iso- and hyperosmotically shrunken HUVEC. Methods: Cell volume was measured by 3D reconstruction of cell shape and as 14C-urea available space. Intracellular Na+ and K+ content was measured by flame atomic absorption spectrometry. ERG transcription was estimated by RT-PCR. Results: Elevation of medium osmolality by 150 mM mannitol or cell transfer from hypo- to isosmotic medium decreased cell volume by 40-50%. Hyperosmotic medium increased [Na+]i by 2-fold whereas isosmotic shrinkage had no impact on this parameter. Hyperosmotic but not isosmotic shrinkage increased up-to 5-fold the content of EGR1, FOS, ATF3, ZFP36 and JUN mRNAs. Expression of these ERGs triggered by hyperosmotic shrinkage and Na+,K+-ATPase inhibition by 0.1 µM ouabain exhibited positive correlation (R²=0.9383, p=0.0005). Isosmotic substitution of NaCl by N-methyl-D-glucamine abolished an increment of [Na+]i and ERG expression triggered by mannitol addition. Conclusion: Augmented expression of ERGs in hyperosmotically shrunken HUVEC is mediated by elevation of [Na+]i. [ABSTRACT FROM AUTHOR]

• Acute restrain stress changes food foraging behavior in both social or nonsocial settings. • Acute restrain stress affects the social-based more than value-based food foraging decision-making behavior. • Acute restrain stress enhances Social agonistic, but not social interaction behavior. • The neuronal activation of ACC caused by acute restrain stress could be the reason of inhibited food foraging. Stress can influence decision-making in humans from many cognitive perspectives, while the underlying neurobiological mechanism remains incompletely understood. Food-foraging is a rodent behavior involving strategic possessing of nutritional supply in social context; experimental model of this behavior could help explore the effect of stress on decision-making and the brain mechanism thereof. In the present study, the influence of stress on food-foraging behavior was assessed in rats using an open field choosing paradigm wherein food collection (standard food or sweet food) were associated with social competition (with or without a rat in the cage). Acute restraint stress (ARS) was induced by placing the rat in a plastic restrainer for 2 h before food-foraging behavioral tests, with the effect of stress also determined biochemically and immunohistochemically. Restraint stressed rats showed anxiety-like behavior and elevation of serum corticosterone (CORT) and epinephrine (EPI) relative to controls. Both restraint and control animals preferred sugared food. However, the former group tended to forage food from a cage not occupied by a conspecific rat, whereas the control rats preferred to obtain food from the cage with a social competitor. Thus, the total amount of food foraged and eaten are reduced in the restrained rats than in controls. While the restraint animals had normal social interaction with other rats, they displayed enhanced social agonistic behavior. In brain examination, ARS attenuated the increase in immunolabeling and protein levels of c-fos, p-CREB, p-ERK1/2 in the anterior cingulate cortex (ACC) observed in control animals in association with food-foraging. These results indicate that restraint stressed rats tend to forage food by taking the advantage of a less competitive opportunity. Mechanistically, this decision-making alternative appears to be mediated through a neuronal deactivation in the ACC. The current findings provide novel insights into neuronal processing of decision-making behavior under the influence of stress. [ABSTRACT FROM AUTHOR]

The Leydig tumor cell line, MA-10, expresses the luteinizing hormone receptor, a G protein-coupled receptor that, when activated with luteinizing hormone or chorionic gonadotropin (CG), stimulates cAMP production and subsequent steroidogenesis, notably progesterone. These cells also respond to epidermal growth factor (EGF) and phorbol esters with increased steroid biosynthesis. In order to probe the intracellular pathways along with heterologous receptor down-regulation and cellular desensitization, cells were preincubated with EGF or phorbol esters and then challenged with CG, EGF, dibutryl-cyclic AMP, and a phorbol ester. Relative receptor numbers, steroid biosynthesis, and expression of the early response genes, JUNB and c-FOS, were measured. It was found that in all cases but one receptor down-regulation and decreased progesterone production were closely coupled under the conditions used; the exception involved preincubation of the cells with EGF followed by addition of CG where the CG-mediated stimulation of steroidogenesis was considerably lower than the level of receptor down-regulation. In a number of instances JUNB and c-FOS expression paralleled the decreases in receptor number and progesterone production, while in some cases these early response genes were affected little if at all by the changes in receptor number. This finding may indicate that even low levels of activated signaling kinases, e.g. protein kinase A, protein kinase C, or receptor tyrosine kinase, may suffice to yield good expression of JUNB and c-FOS, or it may suggest alternative pathways for regulating expression of these two early response genes.

Right ventricular dysfunction is a key clinical issue for the viability of donation-after-circulatory-death (DCD) heart transplantation. DCD hearts with volume overload have the potential to exhibit aggravated right ventricular dysfunction following heart transplantation. The c-jun/c-fos mRNAs are genes that immediately respond to myocardial cell stretch. We assessed myocardial cell stretch during asphyxia-induced cardiac arrest by measuring c-jun/c-fos mRNA expression levels. The trachea was dissected and ligated to initiate asphyxiation in anesthetized Wistar rats under paralyzed ventilation. The hearts were harvested at 4 time points: 0, 15, 30, and 45 minutes after the termination of ventilation. Free walls of the right and left ventricles and the interventricular septum were sectioned. Total RNA was extracted from these tissues, and cDNA was synthesized using reverse transcription. The c-jun/c-fos mRNA expression levels were quantified using the droplet digital polymerase chain reaction method. In the left ventricle, c-jun/c-fos expression levels rapidly increased at 15 minutes, but the expression levels returned to the baseline level at 30 minutes after tracheal ligation. In contrast, in the right ventricle, c-jun/c-fos expression levels gradually increased and peaked 30 minutes after tracheal ligation. Myocardial cell stretching in the right ventricle is prolonged after asphyxia-induced cardiac arrest compared to that in the left ventricle, which may lead to right ventricular dysfunction after DCD heart transplantation.

Early response genes are a group of proto-oncogenes that are the first to be activated in cell stimulation with different growth factors and to be involved in the regulation of cell proliferation and differentiation. Large amount of information supporting that altered expression of these genes is one of the central and earliest events of carcinogenesis has been accumulated. In this connection, it is promising to use early response genes as diagnostic and prognostic markers for the detection and combination therapy of cancer of the cervix uteri, one of the most common gynecological malignancies characterized by high mortality rates and difficulties in early diagnosis. The theoretical basis for these promises is the found mechanisms for the interaction of early response genes with human papillomavirus genome, the main cause of cervix uteri cancer.

Key message: Dynamic transcriptional changes of the host early responses genes were detected in PVY-resistant tobacco varieties infected with Potato virus Y; PVY resistance is a complex process that needs series of stress responses. Abstract: Potato virus Y (PVY) causes a severe viral disease in cultivated crops, especially in Solanum plants. To understand the molecular basis of plant responses to the PVY stress, suppression subtractive hybridization (SSH) and microarray approaches were combined to identify the potentially important or novel genes that were involved in early stages (12 h, 1, 2, 3, 5, 8 days) of tobacco response to PVY infection. Dynamic changes of the host plant early responses to PVY infection on a transcriptional level were detected. In total, 167 different expressed ESTs were identified. The majority of genes involved in the metabolic process were found to be down-regulated at 12 h and 1 day, and then up-regulated at least one later period. Genes related to signaling and transcriptions were almost up-regulated at 12 h, 1 or 2 days, while stress response genes were almost up-regulated at a later stage. Genes involved in transcription, transport, cell wall, and several stress responses were found to have changed expression during the PVY infection stage, and numbers of these genes have not been previously reported to be associated with tobacco PVY infection. The diversity expression of these genes indicated that PVY resistance is a complex process that needs a series of stress responses. To resist the PVY infection, the tobacco plant has numerous active and silent responses. [ABSTRACT FROM AUTHOR]

Background: Pirfenidone was recently approved for treatment of idiopathic pulmonary fibrosis. However, the therapeutic dose of pirfenidone is very high, causing side effects that limit its doses and therapeutic effectiveness. Understanding the molecular mechanisms of action of pirfenidone could improve its safety and efficacy. Because activated fibroblasts are critical effector cells associated with the progression of fibrosis, this study investigated the genes that change expression rapidly in response to pirfenidone treatment of pulmonary fibroblasts and explored their contributions to the anti-fibrotic effects of pirfenidone.Methods: We used the GeneChip microarray to screen for genes that were rapidly up-regulated upon exposure of human lung fibroblast cells to pirfenidone, with confirmation for specific genes by real-time PCR and western blots. Biochemical and functional analyses were used to establish their anti-fibrotic effects in cellular and animal models of pulmonary fibrosis.Results: We identified Regulator of G-protein Signaling 2 (RGS2) as an early pirfenidone-induced gene. Treatment with pirfenidone significantly increased RGS2 mRNA and protein expression in both a human fetal lung fibroblast cell line and primary pulmonary fibroblasts isolated from patients without or with idiopathic pulmonary fibrosis. Pirfenidone treatment or direct overexpression of recombinant RGS2 in human lung fibroblasts inhibited the profibrotic effects of thrombin, whereas loss of RGS2 exacerbated bleomycin-induced pulmonary fibrosis and mortality in mice. Pirfenidone treatment reduced bleomycin-induced pulmonary fibrosis in wild-type but not RGS2 knockout mice.Conclusions: Endogenous RGS2 exhibits anti-fibrotic functions. Upregulated RGS2 contributes significantly to the anti-fibrotic effects of pirfenidone. [ABSTRACT FROM AUTHOR]

This article reviews recent results of studies aiming to elucidate modes of integrating signals initiated in ACTH receptors and FGF2 receptors, within the network system of signal transduction found in Y1 adrenocortical cells. These modes of signal integration should be central to the mechanisms underlying the regulation of the G0->G1->S transition in the adrenal cell cycle. FGF2 elicits a strong mitogenic response in G0/G1-arrested Y1 adrenocortical cells, that includes a) rapid and transient activation of extracellular signal-regulated kinases-mitogen-activated protein kinases (ERK-MAPK) (2 to 10 min), b) transcription activation of c-fos, c-jun and c-myc genes (10 to 30 min), c) induction of c-Fos and c-Myc proteins by 1 h and cyclin D1 protein by 5 h, and d) onset of DNA synthesis stimulation within 8 h. ACTH, itself a weak mitogen, interacts with FGF2 in a complex manner, blocking the FGF2 mitogenic response during the early and middle G1 phase, keeping ERK-MAPK activation and c-Fos and cyclin D1 induction at maximal levels, but post-transcriptionally inhibiting c-Myc expression. c-Fos and c-Jun proteins are mediators in both the strong and the weak mitogenic responses respectively triggered by FGF2 and ACTH. Induction of c-Fos and stimulation of DNA synthesis by ACTH are independent of PKA and are inhibited by the PKC inhibitor GF109203X. In addition, ACTH is a poor activator of ERK-MAPK, but c-Fos induction and DNA synthesis stimulation by ACTH are strongly inhibited by the inhibitor of MEK1 PD98059.

Neuronal activity induces topoisomerase IIβ (Top2B) to generate DNA double-strand breaks (DSBs) within the promoters of neuronal early response genes (ERGs) and facilitate their transcription, and yet, the mechanisms that control Top2B-mediated DSB formation are unknown. Here, we report that stimulus-dependent calcium influx through NMDA receptors activates the phosphatase calcineurin to dephosphorylate Top2B at residues S1509 and S1511, which stimulates its DNA cleavage activity and induces it to form DSBs. Exposing mice to a fear conditioning paradigm also triggers Top2B dephosphorylation at S1509 and S1511 in the hippocampus, indicating that calcineurin also regulates Top2B-mediated DSB formation following physiological neuronal activity. Furthermore, calcineurin-Top2B interactions following neuronal activity and sites that incur activity-induced DSBs are preferentially localized at the nuclear periphery in neurons. Together, these results reveal how radial gene positioning and the compartmentalization of activity-dependent signaling govern the position and timing of activity-induced DSBs and regulate gene expression patterns in neurons. [Display omitted] • Calcineurin activates Top2B and induces it to form DSBs in response to NMDAR activity • Calcineurin dephosphorylates Top2B at residues S1509 and S1511 within its C-terminal • Calcineurin-mediated DSBs regulate the expression of neuronal early response genes • Neuronal-activity-induced DSB sites preferentially localize to the nuclear periphery Here, we report that neuronal stimulation triggers the phosphatase calcineurin to dephosphorylate the topoisomerase Top2B and induce it to form DNA breaks within the promoters of neuronal early response genes, which, in turn, promotes their rapid transcription. We further show that these events are compartmentalized at the nuclear periphery. [ABSTRACT FROM AUTHOR]

The visual system of vertebrates consists of an image-forming and a non-image-forming optic system; the image-forming optic system involves the classic photoreceptors, the rods and cones, whereas the non-image-forming optic system involves the melanopsin-containing retinal ganglion cells. Both optic systems make direct neuroanatomical connections to the suprachiasmatic nucleus (SCN) in the hypothalamus in which the biological clock of vertebrates is located. The rhythmic output from SCN neurons is entrained by light via the retina and the retinohypothalamic tract. The response of exposure to light during the subjective night is an immediate expression of several early response genes in the SCN. We show, by quantitative real-time polymerase chain reaction, that the amount of melanopsin mRNA in the retinal ganglion cells is preserved in the blind Crx mouse with degenerated classic photoreceptors. At zeitgeber time 16, the Crx and wild-type mice were exposed to 1 h of light. This resulted in a strong up-regulation of the immediate early genes Nr4a1, Erg, and Rrad in the SCN of both genotypes. Light stimulation during the subjective night resulted in a strong up-regulation of c-fos in both genotypes with a significantly higher up-regulation in the blind Crx mouse. Expression of Grp and Vip, the genes for two classic peptides located in the SCN, was not influenced by light stimulation. The data strongly indicate the involvement of the melanopsin-based non-visual optic system in the regulation of immediate early genes in the SCN. [ABSTRACT FROM AUTHOR]

Mechanical loading increases the strength of healing tendons, but also induces small localized bleedings. Therefore, it is unclear if increased strength after loading is a response to mechanotransduction or microtrauma. We have previously found only five genes to be up-regulated 15 min after a single loading episode, of them four were transcription factors. These genes are followed by hundreds of genes after 3 h, many of them involved in inflammation. We now compared healing in mechanically unloaded tendons with or without added microtrauma induced by needling of the healing tissue. Nineteen rats received Botox into the calf muscle to reduce loading, and the Achilles tendon was transected. Ten rats were randomized to needling days 2-5. Mechanical testing on day 8 showed increased strength by 45% in the needling group. Next, another 24 rats were similarly unloaded, and 16 randomized to needling on day 5 after transection. Nineteen characteristic genes, known to be regulated by loading in this model, were analyzed by qRT-PCR. Four of these genes were regulated 15 min after needling. Three of them (Egr1, c-Fos, Rgs1) were among the five regulated genes after loading in a previous study. Sixteen of the 19 genes were regulated after 3 h, in the same way as after loading. In conclusion, needling increased strength, and there was a striking similarity between the gene expression response to needling and mechanical loading. This suggests that the response to loading in early tendon healing can, at least in part, be a response to microtrauma. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the expression of calcitonin gene–related peptide (CGRP) and its role in the liver regeneration process after 70% hepatectomy (Hx). Materials and methods: Wistar rats were divided into eight groups based on time after Hx. Remnant liver samples were collected serially 0 h, 1 h, 6 h, 12 h, 1 d, 2 d, 7 d, and 14 d after Hx (n = 6 for each time point). The expression level of the calcitonin/CGRP gene in the remnant liver was measured. Western bolts and immunohistochemistry were performed to determine the levels of CGRP in the regenerating liver. Furthermore, CGRP8-37 (a CGRP receptor antagonist) was used to examine the role of CGRP during liver regeneration. Results: A marked upregulation of the calcitonin/CGRP gene was observed immediately after Hx, and the protein levels of CGRP in the liver, which were measured by western blot and immunohistochemistry, also rapidly increased after Hx. The liver regeneration rate was significantly attenuated by an administration of CGRP8-37 2 d after Hx. The mitotic index was evaluated by histologic examination 1 and 2 d after Hx and was also significantly lower in the CGRP8-37 group. In addition, CGRP8-37 treatment inhibited the phosphorylation of extracellular-signal regulated kinase 1/2. The levels of early response genes, such as c-fos, c-jun, and c-myc, were also downregulated by CGRP8-37. Conclusion: The calcitonin/CGRP gene may have an important role in the early phase of liver regeneration after Hx. [Copyright &y& Elsevier]

Nuclear calcium signalling has been an important topic of investigation for many years and some aspects have been the subject of debate. Our data from isolated nuclei suggest that the nuclear pore complexes (NPCs) are open even after depletion of the Ca2+ store in the nuclear envelope (NE). The NE contains ryanodine receptors (RyRs) and Ins(1,4,5)P3 receptors [Ins(1,4,5)P3Rs], most likely on both sides of the NE and these can be activated separately and independently: the RyRs by either NAADP or cADPR, and the Ins(1,4,5)P3Rs by Ins(1,4,5)P3. We have also investigated the possible consequences of nuclear calcium signals: the role of Ca2+ in the regulation of immediate early genes (IEG): c-fos, c-myc and c-jun in pancreatic acinar cells. Stimulation with Ca2+-mobilizing agonists induced significant increases in levels of expression. Cholecystokinin (CCK) (10 nm) evoked a substantial rise in the expression levels, highly dependent on external Ca2+: the IEG expression level was lowest in Ca2+-free solution, increased at the physiological level of 1 mm [Ca2+]o and was maximal at 10 mm [Ca2+]o, i.e.: 102 ± 22% and 163 ± 15% for c-fos; c-myc −73 ± 13% and 106 ± 24%; c-jun −49 ± 8% and 59 ± 9% at 1 and 10 mm of extracellular Ca2+ respectively. A low CCK concentration (10 pm) induced a small increase in expression. We conclude that extracellular Ca2+ together with nuclear Ca2+ signals induced by CCK play important roles in the induction of IEG expression. [ABSTRACT FROM AUTHOR]

Abstract: Pathogen–host interaction plays an essential role in pathogenicity. In this study, we investigated transcriptomes of one Streptococcus pneumoniae TIGR4-derived unencapsulated strain upon exposure to THP-1 human macrophage-like cells for 0.5 h, 1 h and 3 h, respectively. Expression of most genes was up-regulated and the changes of selected genes were validated by qRT-PCR. To characterize the functions of the identified genes, one locus of genes (SP1057–SP1063) was deleted in TIGR4 by insertion replacement mutagenesis. Compared to the wild-type strain, the constructed mutant exhibited lower binding and internalization activities to the THP-1 macrophages at early incubation time periods (0.5 h and/or 1 h) but not at 3 h. However, no change was observed in the intracellular survival assays. These data indicate that the SP1057–SP1063 locus is involved in the early stage of interaction with host macrophages. Further sequence and PCR analyses suggest that the SP1057–SP1063 locus was acquired by lateral transfer. [Copyright &y& Elsevier]

Pituitary adenylate cyclase-activating polypeptide (PACAP) promotes neurite outgrowth, reduces proliferation and inhibits apoptosis of PC12 cells. We have partially characterized the transcriptome changes induced by PACAP after 6 h of treatment, when commitment to differentiation has occurred. Here, we have investigated the effects of a 6-h treatment with PACAP (10−7 m) in the presence of cycloheximide (5 µm) to identify, via superinduction, components of the transitional transcriptome initially induced by PACAP and potentially participating in the regulation of late-response genes required for differentiation. Approximately 100 new transcripts were identified in this screen, i.e. as many individual genes as make up the 6-h PACAP differentiation transcriptome itself. Six known transcripts in this cohort were then measured at several time points between 0 and 6 h by real-time PCR to determine whether these transcripts are induced early following PACAP treatment in the absence of cycloheximide, and therefore may be of functional importance in differentiation. Five out of the six transcripts were indeed induced by PACAP alone soon (between 30 min and 3 h) after cell treatment. β-Cell translocation gene 2, antiproliferative ( Btg2), serum/glucocorticoid-regulated kinase (Sgk), nuclear factor for the κ chain of B-cells ( NFκB), seven in absentia homologue 2 (Siah2) and FBJ osteosarcoma related oncogene ( Fos) showed a 2.5–200-fold induction by PACAP between 15 min and 3 h, and mRNA levels returned either to baseline or near baseline after 6 h. This work provides new information concerning genes whose transient regulation early after PACAP exposure may contribute to the expression of the differentiated transcriptome in PC12 cells, and should help to elucidate the molecular mechanisms involved in the control of nerve cell survival and differentiation. [ABSTRACT FROM AUTHOR]

Focuses on molecular mechanisms for the growth factor action of gastrin. Intracellular signal transduction pathways regulating cellular proliferation; Elucidation of the molecular mechanisms responsible for the growth factor action of gastrin.

Abstract: H2O2-induced onset and execution of programmed cell death in mature rat brain oligodendrocytes in culture is accompanied by the induction and nuclear translocation of the transcription factors AP-1 and nuclear factor-κB (NF-κB), both of which have been discussed as regulators of cell death and survival. Supershift analysis of nuclear extracts indicated that the AP-1 complex consists of c-Jun, c-Fos, JunD, and possibly JunB proteins, and that the NF-κB complex contains p50, p65, and c-Rel proteins. The first signs of DNA fragmentation were seen already during the first hour after the treatment. DNA fragmentation could be prevented by the antioxidants pyrrolidine dithiocarbamate and vitamin E, by the nuclease inhibitor aurintricarboxylic acid, and by preincubation with the iron chelator deferoxamine (DFO). Additionally, DFO protected oligodendrocytes from H2O2-induced cytotoxic effects as assessed by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, and suppressed the formation of free radicals. DFO alone led to a slight increase and in combination with H2O2 synergistically induced DNA-binding activities of AP-1 and NF-κB in oligodendrocytes. Our data suggest that although low levels of H2O2 directly activate AP-1 and NF-κB and might contribute to signal transduction pathways promoting cell survival, the formation and action of hydroxyl radicals promote cell death mechanisms that can be attenuated by the iron chelator DFO. [ABSTRACT FROM AUTHOR]

Luminal and systemic short chain fatty acids (SCFA) stimulate mucosal proliferation but the mechanism(s) is unclear. This study examined acute effects of systemic SCFAs on gastrointestinal structure and function and signals potentially mediating SCFA-induced mucosal proliferation. Male Sprague-Dawley rats (246+/-2 g) received nutrients as either standard total parenteral nutrition (TPN) or an isoenergetic, isonitrogenous formulation containing SCFAs (TPN + SCFA). Animals were randomized to one of five treatments: standard TPN for 72 hr, TPN + SCFA for 72 hr, or standard TPN followed by TPN + SCFA for the final 6, 12, and 24 hr. SCFAs reduced (P < 0.003) ileal protein within 6 hr. Jejunal GLUT2 expression was increased (P=0.0001) in all SCFA groups and ileal GLUT2 protein in the 6-, 12-, and 24-hr SCFA groups (P < 0.05). SCFAs increased (P < 0.003) ileal proglucagon abundance following 6, 12, and 24 hr, and plasma GLP-2 concentration following 12 hr (P < 0.03). Jejunal c-myc expression was increased (P < 0.001) following 6, 12, and 24 hr of SCFAs. SCFAs increased ileal c-myc, c-jun, and c-fos expression following 24 hr (P < 0.02), 12 hr (P < 0.05) and 6, 12, and 24 hr (P=0.0001), respectively. In conclusion, systemic SCFAs increase plasma GLP-2 and ileal proglucagon mRNA, GLUT2 expression and protein, and c-myc, c-jun, and c-fos expression. [ABSTRACT FROM AUTHOR]

Objective: Important physiological and pathophysiological conditions are associated with changes in secretion and synthesis of atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP). The aim of this study was to examine the effects of mechanical stretch and endothelin-1 on ANF and BNP secretion and gene expression in isolated adult rat atria, as paradigms for mechanical and endocrine stimulation of atrial tissue. The expression of the early response genes c-fos, c-jun, Egr-1, and c-myc was also studied, since their protein products may be involved in controlling natriuretic peptide gene expression. Methods: Isolated rat atria were stimulated by stretch (5 g) or endothelin-1 (10−7 M) for 30 min, 2 h, or 4 h. ANF and BNP secretion was measured by radioimmunoassay, and relative mRNA levels were determined by northern blotting. Results: Atrial stretch resulted in an immediate 1.8-fold increase in ANF release, which returned to basal levels after 160 min. Endothelin-1 caused a gradual increase in ANF release, up to 2.3 times basal levels, and thereafter returned towards basal levels. BNP secretion was increased threefold by endothelin-1, and remained significantly raised for 90 min. BNP mRNA levels were transiently increased by 33% after 2 h of endothelin-1 stimulation. Stretch increased c-fos mRNA levels (+55%) and Egr-1 mRNA levels (+70%) after 2 h, and increased c-myc mRNA levels (+69%) after 4 h. Endothelin-1 increased Egr-1 mRNA levels up to +767% after 4 h. Conclusions: Endothelin-1 stimulates BNP secretion from rat atria; this is followed by an increase in BNP mRNA levels. Conversely, acute secretion of ANF by stretch or endothelin-1 is not accompanied by changes in ANF mRNA levels. Atrial stretch results in changes in the expression of the early response genes c-fos, Egr-1, and c-myc, while endothelin-1 stimulates Egr-1 expression. The specific changes in natriuretic peptide and early response gene expression reveal distinct mechanisms of modulation of atrial gene expression by mechanical and endocrine stimuli.Cardiovascular Research 1994;28:1519-1525 [ABSTRACT FROM PUBLISHER]

To develop a new antiviral preparation from a microbial source, the halophilic bacterium Bacillus pumilus E303035 was isolated from a soil sample collected at Qarhan Salt Lake in Qinghai, China. The inhibitory activity of an ethyl acetate extract of its fermentation broth was higher than that of an n-butanol extract. After isolation and purification, 9 compounds were obtained: cyclo(L-Leu-L-Pro) (1), cyclo(L-Pro-L-Tyr) (2), Brevianamide F (3), 2-(3-Indolyl) ethanol (4), N-[2-(1H-indol-3-yl) ethyl] acetamide (5), 3, 3-di(1H-indol-3-yl)propane-1,2-diol (6), Lincomycin B (7), dibutylphthalate (8), and p-hydroxyphenethyl alcohol (9). Compounds 1, 5, and 9 showed inhibitory activities against potato virus Y (PVY). Compounds 1, 4, and 9 had significant inhibitory activity against genes HC-pro, P3, and Nib, compound 5 against gene P3, and compounds 1 and 4 against NIa. Compounds 1, 4, 5, and 9 had significant inhibitory activity against genes VPg and 6K1. Active compounds 1, 5, and 9 had various effects on the expression of viral genes related to pathogenesis. Expression of genes cullin and XTH was up-regulated and CP was down-regulated, compared to the positive control. In conclusion, compounds 1, 5, and 9 might be considered as potential antiviral agents for future development. [ABSTRACT FROM AUTHOR]

State of the art techniques have been developed to isolate and analyze cells from various tissues, aiming to capture their in vivo state. However, the majority of cell isolation protocols involve lengthy mechanical and enzymatic dissociation steps followed by flow cytometry, exposing cells to stress and disrupting their physiological niche. Focusing on adult skeletal muscle stem cells, we have developed a protocol that circumvents the impact of isolation procedures and captures cells in their native quiescent state. We show that current isolation protocols induce major transcriptional changes accompanied by specific histone modifications while having negligible effects on DNA methylation. In addition to proposing a protocol to avoid isolation-induced artifacts, our study reveals previously undetected quiescence and early activation genes of potential biological interest., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

In vitro phorbol ester-induced plasmacytoid differentiation of primary B chronic lymphocytic leukaemia (BCLL) cells is accompanied by the rapid, transient increased expression of a large number of early response genes (ERGs) whose expression is highly cell type specific. We have examined phorbol ester-responsive expression of a panel of 13 ERGs in a series of B cell lines representing different stages of differentiation and in primary malignant cells from patients with hairy cell leukaemia and with centroblastic-centrocytic non-Hodgkin's lymphoma. The results revealed a spectrum of ERG expression which appeared to be correlated with stage of differentiation relative to BCLL cells, where no two cell types gave an identical ERG response. These results, while preliminary, suggest that panels of ERG probes provide a useful approach for analysis of cell type which may help in mapping stages of differentiation arrest and defining cell lineage relationships amongst mature B cell malignancies.