Purpose: To investigate whether dexamethasone has an effect on functional expression of p-glycoprotein in cultured human retinal pigment epithelium (RPE) and, if so, whether this occurs through interaction with glucocorticoid receptor (GR) and pregnane X receptor (PXR).Methods: The human RPE D407 was treated with increasing concentrations of dexamethasone and/or RU486 ...

In the present study, transcriptional and post-translational effects of culturing time and prototypical cytochrome P450 3A (CYP3A) inducers on principal nuclear receptors (NRs), CYP2B22, 2C and 3A were investigated in long-term stored (~10 years) cryopreserved pig hepatocvytes (CPHs). In the time-course study, a crush and rise effect was observed for ...

TAZ (transcriptional co-activator with PDZ binding motif) is a transcriptional modulator of mesenchymal stem cell differentiation. We have found that TAZ was expressed in postconfluent 3T3-L1 preadipocytes and downregulated during differentiation. Downregulation of TAZ was specifically mediated by dexamethasone (DEX), one component of induction cocktails routinely used in adipocyte differentiation. ...

MicroRNAs (miRNAs) are endogenous single-stranded, 22-nt (nucleotide) RNAs which complement mRNA to initiate post-transcriptional regulation. This review presents updates and evaluations of the public domain resources available for miRNA identification and target prediction toward their utilization in the biomedical research approach. This study discusses the basic principles of miRNA computational ...

The Y loops of Drosophila spermatocytes are formed by the expression of huge individual transcription units on the Y chromosome and their large size provides a unique system for the investigation of the organisation of transcription in intact nuclei. By labelling ribonucleo-protein (RNP) components, the loop chromatin and nascent transcripts ...

Annexin A7 is a member of the family of annexins, which are thought to function in the regulation of calcium homeostasis and the fusion of vesicles. Refractory epilepsy may be related to the imbalance of calcium homeostasis. Our aims are to investigate the expression of Annexin A7 in epileptic brains ...

Varicella zoster virus (VZV) is highly cell-associated. At least 68 VZV open reading frames (ORFs) are transcribed in varying amounts that increase as infection progresses. Using reverse transcriptase PCR, quantification of total and newly synthesized mRNA showed that ongoing VZV DNA replication is required for continued accumulation of VZV ORF ...

Two studies tested whether observers could differentiate between two facets of pride-authentic and hubristic-on the basis of a single prototypical pride nonverbal expression combined with relevant contextual information. In Study 1, participants viewed targets displaying posed pride expressions in response to success, while causal attributions for the success (target's effort ...

The ciliary marginal zone (CMZ) of fish and frog retinas contains cells that proliferate throughout postembryonic development as the retina grows with increasing body size, indicating the presence of stem cells in this region. However, neither the location nor the molecular identity of retinal stem cells have been identified. Here, ...

achaete-scute complex (ASC) genes, which encode basic helix-loop-helix transcription factors, regulate embryonic and adult neurogenesis in many animals. In adult arthropods, including crustaceans, ASC homologs have been identified but rarely functionally characterized. We took advantage of the recently identified crustacean homolog, splash (spiny lobster achaete scute homolog), in the olfactory ...

Background.  Wnt10b (wingless-related mouse mammary tumour virus integration site 10b) plays various roles in a wide range of biological actions, including hair-follicle development. Aim.  To assess the roles that Wnt10b plays in postnatal hair-follicle growth. Methods.  Adenovirus vectors AdWnt10b, AdGFP, AdGFP plus AdRFP, AdWnt10b plus AdFrzB, and AdWnt10b plus AdSimBC ...

Atypical (dysplastic) melanocytic nevi are clinically heterogeneous malignant melanoma precursors, for which no topographic analysis of cell kinetic, cell cycle regulators and microsatellite profile is available. We selected low-grade atypical melanocytic nevi (92), high-grade atypical melanocytic nevi (41), melanocytic nevi (18 junctional, 25 compound) and malignant melanomas (16 radial growth ...

A Cre/loxP-based fate mapping approach was used to follow the regions of the mouse thyroid labeled by the serotonin transporter SERT. Reporter gene expression (lacZ) is activated by Cre expression from the SERT locus in SERT(Cre/+) ;ROSA26R compound mouse embryos. Cell labeling, first detected in the thyroid primordium at the ...

Pancreatic and duodenal homeobox (Pdx1) is a homeobox transcription factor required for the embryonic development of the pancreas. Pdx1 expression has been earlier identified in pancreatic ductal adenocarcinomas and endocrine neoplasms. This study characterizes Pdx1 protein expression in pancreatic precursor lesions and neoplasms, including pancreatic intraepithelial neoplasia (PanIN, n=32), intraductal ...

The simultaneous localization of several anatomical markers is often required to understand and analyze the organization of complex brain nuclei or identify neuronal networks recruited during a specific biological stimulus. Gathering such information is usually achieved by the combined detection of both mRNA and proteins. Staining techniques using fluorescence have ...

Live-cell single mRNA imaging is a powerful tool but has been restricted in higher eukaryotes to artificial cell lines and reporter genes. We describe an approach that enables live-cell imaging of single endogenous labeled mRNA molecules transcribed in primary mammalian cells and tissue. We generated a knock-in mouse line with ...

The detection of microRNAs (miRNAs) in situ presents several technical challenges. Although protocols for mRNA detection by in situ hybridization are well established, the small size of miRNAs makes their localization problematic. To overcome this, digoxygenin-labeled locked nucleic acid oligos have been used. These bind strongly and specifically to miR ...

Aging is associated with both the disturbances of circadian rhythms and a prothrombotic phenotype. It remains poorly understood how the circadian system regulates thrombosis, a critical outcome of aging-related cardiovascular disease. Using multiple in vivo models, we now show that mice with genetic ablation of the core clock gene Bmal1, ...

achaete-scute complex (ASC) genes, which encode basic helix-loop-helix transcription factors, regulate embryonic and adult neurogenesis in many animals. In adult arthropods, including crustaceans, ASC homologs have been identified but rarely functionally characterized. We took advantage of the recently identified crustacean homolog, splash (spiny lobster achaete scute homolog), in the olfactory ...

Microinjection of Xenopus oocytes or embryos with messenger RNA (mRNA) is a powerful technique for studying development, including protein expression during development. This protocol describes a method for the preparation of secreted (35)S-labeled proteins following mRNA microinjection into Xenopus oocytes.

Recently, it was demonstrated that phosphonate-functionalised nanoparticles were successfully taken up by mesenchymal stem cells without influencing their viability and differentiation capacity, suggesting that they may provide a promising basis for the development of nanoparticles for drug delivery or cell labelling. The present study aimed to investigate the effects of ...

Circadian rhythms regulate a wide variety of physiological and metabolic processes. The clock machinery comprises complex transcriptional-translational feedback loops that, through the action of specific transcription factors, modulate the expression of as many as 10% of cellular transcripts. This marked change in gene expression necessarily implicates a global regulation of ...

Neurokinin B (NKB) and its cognate receptor neurokinin 3 (NK3R) play a critical role in reproduction. NKB and NK3R are coexpressed with dynorphin (Dyn) and kisspeptin (Kiss1) genes in neurons of the arcuate nucleus (Arc). However, the mechanisms of action of NKB as a cotransmitter with kisspeptin and dynorphin remain ...

Circadian clocks control a variety of neuronal, behavioral and physiological responses, via transcriptional regulation of an appreciable portion of the genome. We describe the complex communication network between the brain-specific central clock and the tissue-specific peripheral clocks that serve to synchronize the organism to both external and internal demands. In ...

Negative transcriptional feedback loops are a core feature of eukaryotic circadian clocks and are based on rhythmic interactions between clock-specific repressors and transcription factors. In Drosophila, the repression of dCLOCK (dCLK)-CYCLE (CYC) transcriptional activity by dPERIOD (dPER) is critical for driving circadian gene expression. Although growing lines of evidence indicate ...

The identification of nonporphyrin ligands for the orphan nuclear receptor Rev-erbα will enable studies of its role as a heme sensor and regulator of metabolic and circadian signaling. We describe the development of a biochemical assay measuring the interaction between Rev-erbα and a peptide from the nuclear receptor corepressor-1 (NCoR). ...

The transcription factor CLOCK-BMAL1 is a core component of the molecular clock machinery that drives circadian gene expression and physiology in mammals. Recently, we reported that this heterodimeric transcription factor functions as a signaling molecule in response to the resetting stimuli via the Ca²+-dependent protein kinase C pathway. Here, we ...

The circadian clock of the cyanobacterium Synechococcus elongatus PCC 7942 is built on a three-protein central oscillator that can be reconstituted in vitro, a redox-sensitive input for synchronization with the environment, and a bacterial two-component signal transduction pathway for global transcriptional regulation. This review covers the most recent progress in ...

NF-κB (nuclear factor κB) regulates cellular stress and the immune responses to infection. Its activation results in oscillations in nuclear NF-κB abundance. We treated cells with repeated short pulses of TNFα (tumour necrosis factor α) at various intervals to mimic pulsatile inflammatory signals. At all pulse intervals analysed, we observed ...

Continuous light is a common practice in salmon farming, where it is used to enhance growth, induce smoltification, and regulate puberty. However, knowledge about how different tissues receive information about daylength is limited. The aim of the present study was to evaluate the daily expression of clock (Per1-like, Cry2, and ...

The expression of type I GNRH receptor (GNRHR-I) and the direct role of GNRH-I on corpora lutea (CL) function were studied in the pseudopregnant rabbit model. Immunohistochemistry evidenced GNRHR-I and GNRH-I in luteal cells at early (day 4 pseudopregnancy)-, mid (day 9)-, and late (day 13)-luteal stages. Real-time RT-PCR and ...

ID2 is a rhythmically expressed HLH transcriptional repressor. Deletion of Id2 in mice results in circadian phenotypes, highlighted by disrupted locomotor activity rhythms and an enhanced photoentrainment response. ID2 can suppress the transactivation potential of the positive elements of the clock, CLOCK-BMAL1, on mPer1 and clock-controlled gene (CCG) activity. Misregulation ...

Circadian rhythm is expressed in most organisms, and many functions and parameters in the immune system are associated with time-of-day. However, it is largely unknown if local circadian clocks in immune cells directly control physiological outcomes. We hypothesized that a circadian clock in murine bone marrow derived mast cells (BMMCs) ...

Fibroblast growth factor 21 (FGF21) is a potent antidiabetic and triglyceride-lowering hormone whose hepatic expression is highly responsive to food intake. FGF21 induction in the adaptive response to fasting has been well studied, but the molecular mechanism responsible for feeding-induced repression remains unknown. In this study, we demonstrate a novel ...

Melatonin is an important endocrine signal for darkness in mammals. Transcriptional activation of the arylalkylamine-N-acetyltransferase gene encoding for the penultimate enzyme in melatonin synthesis drives the daily rhythm of the hormone in the pineal gland of rodents. Rhythmic arylalkylamine-N-acetyltransferase expression is controlled by the cAMP-signal transduction pathway and involves the ...

The mammalian clock is regulated at the cellular level by a transcriptional/translational feedback loop. BMAL1/clock (or NPAS2) heterodimers activate the expression of the period (PER) and cryptochrome (CRY) genes acting as transcription factors directed to the PER and CRY promoters via E-box elements. PER and CRY proteins form heterodimers and ...

The epithelial sodium channel (ENaC) mediates the fine-tuned regulation of external sodium (Na) balance. The circadian clock protein Period 1 (Per1) is an aldosterone-induced gene that regulates mRNA expression of the rate-limiting alpha subunit of ENaC (αENaC). In the present study, we examined the effect of Per1 on αENaC in ...

Gonadotropin-releasing hormone (GnRH) signaling regulates reproductive physiology in mammals. GnRH is released by a subset of hypothalamic neurons and binds to GnRH receptor (GnRHR) on gonadotropes in the anterior pituitary gland to control production and secretion of gonadotropins that in turn regulate the activity of the gonads. Central control of ...

An endogenous timing mechanism, the circadian clock, causes rhythmic expression of a considerable fraction of the genome of most organisms to optimally align physiology and behavior with their environment. Circadian clocks are self-sustained oscillators primarily based on transcriptional feedback loops and post-translational modification of clock proteins. It is increasingly becoming ...

Circadian rhythms are driven by oscillating expression of a family of transcription factors called clock genes. In rodents, clock genes drive circadian rhythms in white blood cell function, and glucocorticoids are believed to regulate these rhythms. Little is known about circadian rhythms of cattle white blood cells. The objectives of ...

We examined the role of clock genes in the diurnal regulation of plasma triglyceride-rich apolipoprotein B-lipoproteins and their biosynthetic chaperone, microsomal triglyceride transfer protein (MTP). Clock(mt/mt) mice showed sustained hypertriglyceridemia and high MTP expression. CLOCK knockdown activated MTP promoter and reduced small heterodimer partner (SHP, NROB2). CLOCK upregulated SHP by ...

P-glycoprotein (P-gp) is one of the ATP-binding cassette transporters and acts as an efflux pump for cytotoxic substances. P-gp mRNA expression and transporting activity show the daily rhythm and contribute to the chrono-pharmacokinetic profiles of many drugs. It is reported that the daily rhythm of abcb1a mRNA is regulated by ...

Kisspeptins are a family of neuropeptides encoded by Kiss1 and Kiss2 genes, and participate in neuroendocrine regulation of gonadotropin-releasing hormone (GnRH) secretion through activating their receptor, Kiss1r (or GPR54). Bioinformatic analyses have shown that there is a single gene for each kisspeptin (Kiss2) and its receptor (Kiss1r) in pufferfish, the ...

Molecular studies revealed that autoregulatory negative feedback loops consisting of so-called "clock genes" constitute the circadian clock in Drosophila. However, this hypothesis is not fully supported in other insects and is thus to be examined. In the cricket Gryllus bimaculatus, we have previously shown that period (per) plays an essential ...

Circadian rhythms regulate a wide range of cellular, physiological, metabolic and behavioral activities in mammals. The complexity of tissue- and day-time specific regulation of thousands of clock controlled genes (CCGs) suggests that many transcriptional regulators are involved. Our bioinformatic analysis is based on two published DNA-array studies from mouse liver. ...

To compare circadian gene expression within highly discrete neuronal populations, we separately purified and characterized two adjacent but distinct groups of Drosophila adult circadian neurons: the 8 small and 10 large PDF-expressing ventral lateral neurons (s-LNvs and l-LNvs, respectively). The s-LNvs are the principal circadian pacemaker cells, whereas recent evidence ...

Living organisms undergo biochemical, physiological and behavioral cycles with periods ranging from seconds to years. Cycles with intermediate periods are governed by endogenous clocks that depend on oscillating gene expression. Here we illustrate the modalities and specific functions of post-transcriptional control of gene expression (exerted on pre-mRNAs and mRNAs) in ...

The physiological and behavioral circadian rhythms of most creatures are controlled by a harmony of functional relationships between clock genes. In mammals, several core clock genes show rhythmic profiles of their mRNA and protein expression. Among them, Rev-erb α functions as a transcriptional repressor, affecting expression patterns of other clock ...

Kisspeptin, the product of the KISS1 gene, stimulates gonadotropin-releasing hormone (GnRH) secretion; gonadotropin inhibitory hormone (GnIH), encoded by the RF-amide-related peptide (RFRP) or NPVF gene, inhibits the reproductive axis. In sheep, kisspeptin neurons are found in the lateral preoptic area (POA) and the arcuate nucleus (ARC) and may be important ...

The albumin D site-binding protein (DBP) governs circadian transcription of a number of hepatic detoxification and metabolic enzymes prior to the activity phase and subsequent food intake of mice. However, the behavior of mice is drastically affected by the photoperiod. Therefore, continuous adjustment of the phase of circadian Dbp expression ...