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Found 37769 matches. Displaying 5221-5230
Almey A, Milner TA, Brake WG
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Estrogen receptor alpha and G-protein coupled estrogen receptor 1 are localized to GABAergic neurons in the dorsal striatum

NEUROSCIENCE LETTERS 2016 MAY 27; 622(?):118-123
Estrogens affect dopamine transmission in the striatum, increasing dopamine availability, maintaining D2 receptor density, and reducing the availability of the dopamine transporter. Some of these effects of estrogens are rapid, suggesting that they are mediated by membrane associated receptors. Recently our group demonstrated that there is extra-nuclear labeling for ER alpha, ER beta, and GPER1 in the striatum, but that ER alpha and GPER1 are not localized to dopaminergic neurons in this region. GABAergic neurons are the most common type of neuron in the striatum, and changes in GABA transmission affect dopamine transmission. Thus, to determine whether ER alpha or GPER1 are localized to GABAergic neurons, we double labeled the striatum with antibodies for ER alpha or GPER1 and GABA and examined them using electron microscopy. Ultrastructural analysis revealed that ER alpha and GPER1 are localized exclusively to extranuclear sites in the striatum, and 35% of the dendrites and axon terminals labeled for these receptors contain GABA immunoreactivity. Binding at membrane-associated ER alpha and GPER1 could account for rapid estrogen-induced decreases in GABA transmission in the striatum, which, in turn, could affect dopamine transmission in this region. (C) 2016 Elsevier Ireland Ltd. All rights reserved.
Klose M, Duvall LB, Li WH, Liang XT, Ren C, Steinbach JH, Taghert PH
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Functional PDF Signaling in the Drosophila Circadian Neural Circuit Is Gated by Ral A-Dependent Modulation

NEURON 2016 MAY 18; 90(4):781-794
The neuropeptide PDF promotes the normal sequencing of circadian behavioral rhythms in Drosophila, but its signaling mechanisms are not well understood. We report daily rhythmicity in responsiveness to PDF in critical pacemakers called small LNvs. There is a daily change in potency, as great as 10-fold higher, around dawn. The rhythm persists in constant darkness and does not require endogenous ligand (PDF) signaling or rhythmic receptor gene transcription. Furthermore, rhythmic responsiveness reflects the properties of the pacemaker cell type, not the receptor. Dopamine responsiveness also cycles, in phase with that of PDF, in the same pacemakers, but does not cycle in large LNv. The activity of RalA GTPase in s-LNv regulates PDF responsiveness and behavioral locomotor rhythms. Additionally, cell-autonomous PDF signaling reversed the circadian behavioral effects of lowered RalA activity. Thus, RalA activity confers high PDF responsiveness, providing a daily gate around the dawn hours to promote functional PDF signaling.
Signorile AL, Lurz PWW, Wang J, Reuman DC, Carbone C
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Mixture or mosaic? Genetic patterns in UK grey squirrels support a human-mediated "long-jump' invasion mechanism

DIVERSITY AND DISTRIBUTIONS 2016 MAY; 22(5):566-577
AimClarifying whether multiple introductions of a species remain relatively isolated or merge and interbreed is essential for understanding the dynamics of invasion processes. Multiple introductions from different sources can result in a mixture of genetically distinct populations, increasing the total genetic diversity. This mixing can resolve the genetic paradox', whereby in spite of the relatively small numbers of introduced individuals, the augmented diversity due to this mixing increases adaptability and the ability of the species to spread in new environments. Here, we aim to assess whether the expansion of a successful invader, the Eastern grey squirrel, was partly driven by the merger of multiple introductions and the effects of such a merger on diversity. LocationUK, Ireland. MethodsWe analysed the genetic variation at 12 microsatellite loci of 381 individuals sampled from one historical and 14 modern populations of grey squirrels. ResultsOur data revealed that current UK population structure resembles a mosaic, with minimal interpopulation mixing and each element reflecting the genetic make-up of historic introductions. The genetic diversity of each examined population was lower than a US population or a historical UK population. Numbers of releases in a county did not correlate with county-level genetic diversity. Inbreeding coefficients remain high, and effective population sizes remain small. Main conclusionsOur results support the conclusion that rapid and large-scale expansion in this species in the UK was not driven by a genetic mixing of multiple introduced populations with a single expansion front, but was promoted by repeated translocations of small propagules. Our results have implications for the management of grey squirrels and other invasive species and also demonstrate how invaders can overcome the genetic paradox, if spread is facilitated by human-mediated dispersal.
Kaneto CM, Lima PSP, Zanette DL, Oliveira TYK, Pereira FD, Lorenzi JCC, dos Santos JL, Prata KL, Neto JMP, de Paula FJA, Silva WA
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Osteoblastic differentiation of bone marrow mesenchymal stromal cells in Bruck Syndrome

BMC MEDICAL GENETICS 2016 MAY 4; 17(?):? Article 38
Background: Osteogenesis Imperfecta (OI) (OMIM % 259450) is a heterogeneous group of inherited disorders characterized by increased bone fragility, with clinical severity ranging from mild to lethal. The majority of OI cases are caused by mutations in COL1A1 or COL1A2. Bruck Syndrome (BS) is a further recessively-inherited OI-like phenotype in which bone fragility is associated with the unusual finding of pterygia and contractures of the large joints. Notably, several studies have failed to show any abnormalities in the biosynthesis of collagen 1 in BS patientes. Evidence was obtained for a specific defect of the procollagen telopeptide lysine hydroxylation in BS, whereas mutations in the gene PLOD2 have been identified. Recently, several studies described FKBP10 mutations in OI-like and BS patients, suggesting that FKBP10 is a bonafide BS locus. Methods: We analyzed the coding region and intron/exon boundaries of COL1A1, COL1A2, PLOD2 and FKBP10 genes by sequence analysis using an ABI PRISM 3130 automated sequencer and Big Dye Terminator Sequencing protocol. Mononuclear cells obtained from the bone marrow of BS, OI patients and healthy donors were cultured and osteogenic differentiation was induced. The gene expression of osteoblast specific markers were also evaluated during the osteoblastic differentiation of mesenchymal stem cell (MSC) by qRT-PCR using an ABI7500 Sequence Detection System. Results: No mutations in COL1A1, COL1A2 or PLOD2 were found in BS patient. We found a homozygous 1-base-pair duplication (c.831dupC) that is predicted to produce a translational frameshift mutation and a premature protein truncation 17 aminoacids downstream (p.Gly278ArgfsX95). The gene expression of osteoblast specific markers BGLAP, COL1A1, MSX2, SPARC and VDR was evaluated by Real Time RT-PCR during differentiation into osteoblasts and results showed similar patterns of osteoblast markers expression in BS and healthy controls. On the other hand, when compared with OI patients, the expression pattern of these genes was found to be different. Conclusions: Our work suggests that the gene expression profiles observed during mesenchymal stromal cell differentiation into osteoblast are distinct in BS patients as compared to OI patients. The present study shows for the first time that genes involved in osteogenesis are differentially expressed in BS and OI patients.
Papp KA, Krueger JG, Feldman SR, Langley RG, Thaci D, Torii H, Tyring S, Wolk R, Gardner A, Mebus C, Tan HM, Luo YC, Gupta P, Mallbris L, Tatulych S
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Tofacitinib, an oral Janus kinase inhibitor, for the treatment of chronic plaque psoriasis: Long-term efficacy and safety results from 2 randomized phase-III studies and 1 open-label long-term extension study

JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY 2016 MAY; 74(5):841-850
Background: Tofacitinib is an oral Janus kinase inhibitor being investigated for psoriasis. Objectives:We sought to report longer-term tofacitinib efficacy and safety in patients with moderate to severe psoriasis. Methods: Data from 2 identical phase-III studies, Oral-treatment Psoriasis Trial Pivotal 1 and 2, were pooled with data from these patients in an ongoing open-label long-term extension study. Patients (n = 1861) were randomized 2:2:1 to tofacitinib 5 mg, 10 mg, or placebo twice daily (BID). At week 16, placebo patients were rerandomized to tofacitinib. Pivotal study participants could enroll into the long-term extension where they received tofacitinib at 10 mg BID for 3 months, after which dosing could be 5 or 10 mg BID. Results: At week 28, the proportions of patients randomized to tofacitinib 5 and 10 mg BID achieving 75% or greater reduction in Psoriasis Area and Severity Index score from baseline were 55.6% and 68.8%, and achieving Physician Global Assessment of clear or almost clear were 54.7% and 65.9%. Efficacy was maintained in most patients through 24 months. Serious adverse events and discontinuations because of adverse events were reported in less than 11% of patients over 33 months of tofacitinib exposure. Limitations: There was no dose comparison beyond week 52. Conclusions: Oral tofacitinib demonstrated sustained efficacy in patients with psoriasis through 2 years, with 10 mg BID providing greater efficacy than 5 mg BID. No unexpected safety findings were observed.
Rothschild JB, Tsimiklis P, Siggia ED, Francois P
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Predicting Ancestral Segmentation Phenotypes from Drosophila to Anopheles Using In Silico Evolution

PLOS GENETICS 2016 MAY; 12(5):? Article e1006052
Molecular evolution is an established technique for inferring gene homology but regulatory DNA turns over so rapidly that inference of ancestral networks is often impossible. In silico evolution is used to compute the most parsimonious path in regulatory space for anteriorposterior patterning linking two Dipterian species. The expression pattern of gap genes has evolved between Drosophila (fly) and Anopheles (mosquito), yet one of their targets, eve, has remained invariant. Our model predicts that stripe 5 in fly disappears and a new posterior stripe is created in mosquito, thus eve stripe modules 3+7 and 4+6 in fly are homologous to 3+6 and 4+5 in mosquito. We can place Clogmia on this evolutionary pathway and it shares the mosquito homologies. To account for the evolution of the other pair-rule genes in the posterior we have to assume that the ancestral Dipterian utilized a dynamic method to phase those genes in relation to eve.
Bissonnette R, Suarez-Farinas M, Li X, Bonifacio KM, Brodmerkel C, Fuentes-Duculan J, Krueger JG
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Based on Molecular Profiling of Gene Expression, Palmoplantar Pustulosis and Palmoplantar Pustular Psoriasis Are Highly Related Diseases that Appear to Be Distinct from Psoriasis Vulgaris

PLOS ONE 2016 MAY 6; 11(5):? Article e0155215
Introduction There is a controversy surrounding the existence of palmoplantar pustulosis (PPP) and palmoplantar pustular psoriasis (PPPP) as separate clinical entities or as variants of the same clinical entity. We used gene expression microarray to compare gene expression in PPP and PPPP. Methodology/Principal findings Skin biopsies from subjects with PPP (3), PPPP (6), psoriasis vulgaris (10) and acral skin from normal subjects (7) were analyzed using gene expression microarray. Principal component analysis showed that PPP and PPPP were different from psoriasis vulgaris and normal acral skin. However gene expression of PPP and PPPP clustered together and could not be used to differentiate PPP from PPPP. Gene-wise comparison between PPP and PPPP found no gene to be differentially expressed at a false discovery rate lower than 0.05. Surprisingly we found a higher expression of several genes involved in neural pathways (e.g. GPRIN and ADAM23) in PPP/PPPP as compared to psoriasis vulgaris and normal acral skin. Immunohistochemistry confirmed those findings and showed a keratinocyte localization for those proteins. Conclusion significance PPP and PPPP could not be differentiated using gene expression microarray suggesting that they are not distinct clinical entities. Increased expression of GPRIN1, and ADAM23 in keratinocytes suggests that these proteins could be new therapeutic targets for PPP/PPPP.
Chang GQ, Karatayev O, Lukatskaya O, Leibowitz SF
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Prenatal fat exposure and hypothalamic PPAR beta/delta : Possible relationship to increased neurogenesis of orexigenic peptide neurons

PEPTIDES 2016 MAY; 79(?):16-26
Gestational ex posure to a fat-rich diet, while elevating maternal circulating fatty acids, increases in the offspring's hypothalamus and amygdala the proliferation and density of neurons that express neuropeptides known to stimulate consummatory behavior. To understand the relationship between these phenomena, this study examined in the brain of postnatal offspring (day 15) the effect of prenatal fat exposure on the transcription factor, peroxisome proliferator-activated receptor (PPAR) beta/delta, which is sensitive to fatty acids, and the relationship of PPAR beta/delta to the orexigenic neuropeptides, orexin, melanin-concentrating hormone, and enkephalin. Prenatal exposure to a fat-rich diet compared to low-fat chow increased the density of cells immunoreactive for PPAR beta/delta in the hypothalamic paraventricular nucleus (PVN), perifornical lateral hypothalamus (PFLH), and central nucleus of the amygdala (CeA), but not the hypothalamic arcuate nucleus or basolateral amygdaloid nucleus. It also increased co-labeling of PPAR beta/delta with the cell proliferation marker, BrdU, or neuronal marker, NeuN, and the triple labeling of PPAR beta/delta with BrdU plus NeuN, indicating an increase in proliferation and density of new PPAR beta/delta neurons. Prenatal fat exposure stimulated the double-labeling of PPAR beta/delta with orexin or melanin-concentrating hormone in the PFLH and enkephalin in the PVN and CeA and also triple-labeling of PPAR beta/delta with BrdU and these neuropeptides, indicating that dietary fat increases the genesis of PPAR beta/delta neurons that produce these peptides. These findings demonstrate a close anatomical relationship between PPAR beta/delta and the increased proliferation and density of peptide-expressing neurons in the hypothalamus and amygdala of fat-exposed offspring. (C) 2016 Elsevier Inc. All rights reserved.
Hovel-Miner G, Mugnier MR, Goldwater B, Cross GAM, Papavasiliou FN
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A Conserved DNA Repeat Promotes Selection of a Diverse Repertoire of Trypanosoma brucei Surface Antigens from the Genomic Archive

PLOS GENETICS 2016 MAY; 12(5):? Article e1005994
African trypanosomes are mammalian pathogens that must regularly change their protein coat to survive in the host bloodstream. Chronic trypanosome infections are potentiated by their ability to access a deep genomic repertoire of Variant Surface Glycoprotein (VSG) genes and switch from the expression of one VSG to another. Switching VSG expression is largely based in DNA recombination events that result in chromosome translocations between an acceptor site, which houses the actively transcribed VSG, and a donor gene, drawn from an archive of more than 2,000 silent VSGs. One element implicated in these duplicative gene conversion events is a DNA repeat of approximately 70 bp that is found in long regions within each BES and short iterations proximal to VSGs within the silent archive. Early observations showing that 70-bp repeats can be recombination boundaries during VSG switching led to the prediction that VSG-proximal 70-bp repeats provide recombinatorial homology. Yet, this long held assumption had not been tested and no specific function for the conserved 70-bp repeats had been demonstrated. In the present study, the 70-bp repeats were genetically manipulated under conditions that induce gene conversion. In this manner, we demonstrated that 70-bp repeats promote access to archival VSGs. Synthetic repeat DNA sequences were then employed to identify the length, sequence, and directionality of repeat regions required for this activity. In addition, manipulation of the 70-bp repeats allowed us to observe a link between VSG switching and the cell cycle that had not been appreciated. Together these data provide definitive support for the long-standing hypothesis that 70-bp repeats provide recombinatorial homology during switching. Yet, the fact that silent archival VSGs are selected under these conditions suggests the 70-bp repeats also direct DNA pairing and recombination machinery away from the closest homologs (silent BESs) and toward the rest of the archive.
Hyun I, Wilkerson A, Johnston J
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Revisit the 14-day rule

NATURE 2016 MAY 12; 533(7602):169-171