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A search for a heavy scalar boson H decaying into a pair of lighter standard-model-like 125 GeV Higgs bosons hh and a search for a heavy pseudoscalar boson A decaying into a Z and an h boson are presented. The searches are performed on a data set corresponding to an integrated luminosity of 19.7 fb(-1) of pp collision data at a centre-of-mass energy of 8 TeV, collected by CMS in 2012. A final state consisting of two tau leptons and two b jets is used to search for the H -> hh decay. A final state consisting of two tau leptons from the h boson decay, and two additional leptons from the Z boson decay, is used to search for the decay A -> Zh. The results are interpreted in the context of two-Higgs-doublet models. No excess is found above the standard model expectation and upper limits are set on the heavy boson production cross sections in the mass ranges 260 < m(H) < 350 GeV and 220 < m(A) < 350 GeV. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.

Conventional dendritic cells (cDCs) play an essential role in host immunity by initiating adaptive T cell responses and by serving as innate immune sensors. Although both innate and adaptive functions of cDCs are well documented, their relative importance in maintaining immune homeostasis is poorly understood. To examine the significance of cDC-initiated adaptive immunity in maintaining homeostasis, independent of their innate activities, we generated a cDC-specific Cre mouse and crossed it to a floxed MHC class II (MHC II) mouse. Absence of MHC II on cDCs resulted in chronic intestinal inflammation that was alleviated by antibiotic treatment and entirely averted under germ-free conditions. Uncoupling innate and adaptive functions of cDCs revealed that innate immune functions of cDCs are insufficient to maintain homeostasis and antigen presentation by cDCs is essential for a mutualistic relationship between the host and intestinal bacteria.

The signaling molecule cAMP regulates functions ranging from bacterial transcription to mammalian memory. In mammals, cAMP is synthesized by nine transmembrane adenylyl cyclases (ACs) and one soluble AC (sAC). Despite similarities in their catalytic domains, these ACs differ in regulation. Transmembrane ACs respond to G proteins, whereas sAC is uniquely activated by bicarbonate. Via bicarbonate regulation, sAC acts as a physiological sensor for pH/bicarbonate/CO2, and it has been implicated as a therapeutic target, e.g. for diabetes, glaucoma, and a male contraceptive. Here we identify the bisphenols bithionol and hexachlorophene as potent, sAC-specific inhibitors. Inhibition appears mostly non-competitive with the substrate ATP, indicating that they act via an allosteric site. To analyze the interaction details, we solved a crystal structure of an sAC.bithionol complex. The structure reveals that the compounds are selective for sAC because they bind to the sAC-specific, allosteric binding site for the physiological activator bicarbonate. Structural comparison of the bithionol complex with apo-sAC and other sAC.ligand complexes along with mutagenesis experiments reveals an allosteric mechanism of inhibition; the compound induces rearrangements of substrate binding residues and of Arg(176), a trigger between the active site and allosteric site. Our results thus provide 1) novel insights into the communication between allosteric regulatory and active sites, 2) a novel mechanism for sAC inhibition, and 3) pharmacological compounds targeting this allosteric site and utilizing this mode of inhibition. These studies provide support for the future development of sAC-modulating drugs.

Adult tissue stem cells (SCs) reside in niches, which orchestrate SC behavior. SCs are typically used sparingly and exist in quiescence unless activated for tissue growth. Whether parsimonious SC use is essential to conserve long-term tissue-regenerating potential during normal homeostasis remains poorly understood. Here, we examine this issue by conditionally ablating a key transcription factor Forkhead box C1 (FOXC1) expressed in hair follicle SCs (HFSCs). FOXC1-deficient HFSCs spend less time in quiescence, leading to markedly shortened resting periods between hair cycles. The enhanced hair cycling accelerates HFSC expenditure, and impacts hair regeneration in aging mice. Interestingly, although FOXC1-deficient HFs can still form a new bulge that houses HFSCs for the next hair cycle, the older bulge is left unanchored. As the new hair emerges, the entire old bulge, including its reserve HFSCs and SC-inhibitory inner cell layer, is lost. We trace this mechanism first, to a marked increase in cell cycle-associated transcripts upon Foxc1 ablation, and second, to a downstream reduction in E-cadherin-mediated inter-SC adhesion. Finally, we show that when the old bulge is lost with each hair cycle, overall levels of SC-inhibitory factors are reduced, further lowering the threshold for HFSC activity. Taken together, our findings suggest that HFSCs have restricted potential in vivo, which they conserve by coupling quiescence to adhesion-mediated niche maintenance, thereby achieving long-term tissue homeostasis.

We introduce a novel assay for membrane fusion of solid supported membranes on silica beads and on coverslips. Fusion of the lipid bilayers is induced by bringing an optically trapped bead in contact with the coverslip surface while observing the bead's thermal motion with microsecond temporal and nanometer spatial resolution using a three-dimensional position detector. The probability of fusion is controlled by the membrane tension on the particle. We show that the progression of fusion can be monitored by changes in the three-dimensional position histograms of the bead and in its rate of diffusion. We were able to observe all fusion intermediates including transient fusion, formation of a stalk, hemifusion and the completion of a fusion pore. Fusion intermediates are characterized by axial but not lateral confinement of the motion of the bead and independently by the change of its rate of diffusion due to the additional drag from the stalk-like connection between the two membranes. The detailed information provided by this assay makes it ideally suited for studies of early events in pure lipid bilayer fusion or fusion assisted by fusogenic molecules.

Antibodies made in large animals are integral to many biomedical research endeavors. Domesticated herd animals like goats, sheep, donkeys, horses and camelids all offer distinct advantages in antibody production. However, their cost of use is often prohibitive, especially where poor antigen response is commonplace; choosing a non-responsive animal can set a research program back or even prevent experiments from moving forward entirely. Over the course of production of antibodies from llamas, we found that some animals consistently produced a higher humor al antibody response than others, even to highly divergent antigens, as well as to their standard vaccines. Based on our initial data, we propose that these "high level responders" could be pre-selected by checking antibody titers against common vaccines given to domestic farm animals. Thus, time and money can be saved by reducing the chances of getting poor responding animals and minimizing the use of superfluous animals. (C) 2016 Elsevier B.V. All rights reserved.

The glucagon-like peptide 1 (GLP-1) receptor is a class B G protein-coupled receptor (GPCR) that is a key target for treatments for type II diabetes and obesity. This receptor, like other class B GPCRs, displays biased agonism, though the physiologic significance of this is yet to be elucidated. Previous work has implicated R2.60(190), N3.43(240), Q7.49(394), and H6.52(363) as key residues involved in peptide-mediated biased agonism, with R2.60(190), N3.43(240), and Q7.49(394) predicted to form a polar interaction network. In this study, we used novel insight gained from recent crystal structures of the transmembrane domains of the glucagon and corticotropin releasing factor 1 (CRF1) receptors to develop improved models of the GLP-1 receptor that predict additional key molecular interactions with these amino acids. We have introduced E6.53(364)A, N3.43(240)Q, Q7.49(394)N, and N3.43(240)Q/Q7.49(394)N mutations to probe the role of predicted H-bonding and charge-charge interactions in driving cAMP, calcium, or extracellular signal-regulated kinase (ERK) signaling. A polar interaction between E6.53(364) and R2.60(190) was predicted to be important for GLP-1- and exendin-4-, but not oxyntomodulin-mediated cAMP formation and also ERK1/2 phosphorylation. In contrast, Q7.49(394), but not R2.60(190)/E6.53(364) was critical for calcium mobilization for all three peptides. Mutation of N3.43(240) and Q7.49(394) had differential effects on individual peptides, providing evidence for molecular differences in activation transition. Collectively, this work expands our understanding of peptide-mediated signaling from the GLP-1 receptor and the key role that the central polar network plays in these events.

Estrogen surge following progesterone withdrawal at parturition plays an important role in initiating maternal behavior in various rodent species. Systemic estrogen treatment shortens the latency to onset of maternal behavior in nulliparous female rats that have not experienced parturition. In contrast, nulliparous laboratory mice show rapid onset of maternal behavior without estrogen treatment, and the role of estrogen still remains unclear. Here the effect of systemic estrogen treatment (for 2 h, 1 day, 3 days, and 7 days) after progesterone withdrawal was examined on maternal behavior of C57BL/6 mice. This estrogen regimen led to different effects on nursing, pup retrieval, and nest building behaviors. Latency to nursing was shortened by estrogen treatment within 2 h. Moreover, pup retrieval and nest building were decreased. mRNA expression was also investigated for estrogen receptor a (ER alpha) and for genes involved in regulating maternal behavior, specifically, the oxytocin receptor (OTR) and vasopressin receptor in the medial amygdala (MeA) and medial preoptic area (MPOA). Estrogen treatment led to decreased ER alpha mRNA in both regions. Although OTR mRNA was increased in the MeA, OTR and vasopressin receptor mRNA were reduced in the MPOA, showing region-dependent transcription regulation. To determine the mechanisms for the actions of estrogen treatment, the contribution of estrogen synthesis in the brain was examined. Blockade of estrogen synthesis in the brain by systemic letrozole treatment in ovariectomized mice interfered with pup retrieval and nest building but not nursing behavior, indicating different contributions of estrogen synthesis to maternal behavior. Furthermore, letrozole treatment led to an increase in ER alpha mRNA in the MeA but not in the MPOA, suggesting that involvement of estrogen synthesis is brain region dependent. Altogether, these results suggest that region-dependent estrogen synthesis leads to differential transcriptional activation due to exogenous estrogen treatment, and thereby results in different effects on maternal behavior.

Traits of interest to evolutionary biologists often have complex genetic architectures, the nature of which can confound traditional experimental study at single levels of analysis. In the fire ant Solenopsis invicta, the presence of a Mendelian supergene' is both necessary and sufficient to induce a shift in a fundamental property of social organization, from single-queen (monogyne) to multiple-queen (polygyne) colonies. This selfish genetic element, termed the Social b (Sb) supergene, contains >600 genes that collectively promote its fitness by inducing the characteristic polygyne syndrome, in part by causing polygyne workers to accept only queens bearing the Sb element (a behaviour termed worker Sb discrimination'). Here, we employ a newly developed behavioural assay to reveal that polygyne workers, many of which bear the Sb element, employ chemical cues on the cuticle of queens to achieve worker Sb discrimination, but we found no evidence for such pheromonally mediated worker Sb discrimination in monogyne workers, which universally lack the Sb element. This polygyne worker Sb discrimination was then verified through a green beard' effect previously described in this system. We thus have demonstrated that the Sb element is required both for production of relevant chemical cues of queens and for expression of the behaviours of workers that collectively result in worker Sb discrimination. This information fills a critical gap in the map between genotype and complex phenotype in S.invicta by restricting the search for candidate genes and molecules involved in producing this complex social trait to factors associated with the Sb element itself.

A measurement of vector boson (V) production in conjunction with a D*(2010)(+) meson is presented. Using a data sample corresponding to 9.7 fb(-1) of proton-antiproton collisions at center-of-mass energy root s = 1.96 TeV produced by the Fermilab Tevatron, we reconstruct V + D*+ samples with the CDF II detector. The D*+ is fully reconstructed in the D*(2010)(+) -> D-0 (-> K-pi(+))pi(+) decay mode. This technique is sensitive to the associated production of vector boson plus charm or bottom mesons. We measure the ratio of production cross sections sigma(W + D*) = sigma(W) = [1.75 +/- 0.13(stat) +/- 0.09(stat)]% and sigma(Z + D*)/sigma(Z) = [1.5 +/- 0.4(stat) +/- 0.2(stat)]% and perform a differential measurement of d sigma(W + D*)/dp(T)(D*). Event properties are utilized to determine the fraction of V + D*(2010)(+) events originating from different production processes. The results are in agreement with the predictions obtained with the PYTHIA program, limiting possible contribution from non-standard-model physics processes.