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Jin JJ, Lee M, Bai B, Sun YW, Qu J, Rahmadsyah, Alfiko Y, Lim CH, Suwanto A, Sugiharti M, Wong LS, Ye J, Chua NH, Yue GH
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Draft genome sequence of an elite Dura palm and whole-genome patterns of DNA variation in oil palm

DNA RESEARCH 2016 DEC; 23(6):527-533
Oil palm is the world's leading source of vegetable oil and fat. Dura, Pisifera and Tenera are three forms of oil palm. The genome sequence of Pisifera is available whereas the Dura form has not been sequenced yet. We sequenced the genome of one elite Dura palm, and re-sequenced 17 palm genomes. The assemble genome sequence of the elite Dura tree contained 10,971 scaffolds and was 1.701Gb in length, covering 94.49% of the oil palm genome. 36,105 genes were predicted. Re-sequencing of 17 additional palm trees identified 18.1 million SNPs. We found high genetic variation among palms from different geographical regions, but lower variation among Southeast Asian Dura and Pisifera palms. We mapped 10,000 SNPs on the linkage map of oil palm. In addition, high linkage disequilibrium (LD) was detected in the oil palms used in breeding populations of Southeast Asia, suggesting that LD mapping is likely to be practical in this important oil crop. Our data provide a valuable resource for accelerating genetic improvement and studying the mechanism underlying phenotypic variations of important oil palm traits.
Taylor's law (TL) asserts that the variance in a species' population density is a power-law function of its mean population density: log(variance)=a+bxlog(mean). TL is widely verified. We show here that empirical time series of density of the Hokkaido gray-sided vole, Myodes rufocanus, sampled 1962-1992 at 85 locations, satisfied temporal and spatial forms of TL. The slopes (b +/- standard error) of the temporal and spatial TL were estimated to be 1.613 +/- 0.141 and 1.430 +/- 0.132, respectively. A previously verified autoregressive Gompertz model of the dynamics of these populations generated time series of density which reproduced the form of temporal and spatial TLs, but with slopes that were significantly steeper than the slopes estimated from data. The density-dependent components of the Gompertz model were essential for the temporal TL. Adding to the Gompertz model assumptions that populations with higher mean density have reduced variance of density-independent perturbations and that density-independent perturbations are spatially correlated among populations yielded simulated time series that satisfactorily reproduced the slopes from data. The slopes (b +/- standard error) of the enhanced simulations were 1.619 +/- 0.199 for temporal TL and 1.575 +/- 0.204 for spatial TL.
Vastermark A, Driker A, Weng JW, Li XC, Wang JW, Saier MH
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The V-motifs facilitate the substrate capturing step of the PTS elevator mechanism

JOURNAL OF STRUCTURAL BIOLOGY 2016 DEC; 196(3):496-502
We propose that the alternative crystal forms of outward open UlaA (which are experimental, not simulated, and contain the substrate in the cavity) can be used to interpret/validate the MD results from MalT (the substrate capture step, which involves the mobile second TMSs of the V-motifs, TMSs 2 and 7). Since the crystal contacts are the same between the two alternative crystal forms of outward open UlaA, the striking biological differences noted, including rearranged hydrogen bonds and salt bridge coordination, are not attributable to crystal packing differences. Using transport assays, we identified G58 and G286 as essential for normal vitamin C transport, but the comparison of alternative crystal forms revealed that these residues to unhinge TMS movements from substrate-binding side chains, rendering the mid-TMS regions of homologous TMSs 2 and 7 relatively immobile. While the TMS that is involved in substrate binding in MalT is part of the homologous bundle that holds the two separate halves of the transport assembly (two proteins) together, an unequal effect of the two knockouts was observed for UlaA where both V-motifs are free from such dimer interface interactions. (C) 2016 Elsevier Inc. All rights reserved.
Rasgon NL, McEwen BS
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Insulin resistance-a missing link no more

MOLECULAR PSYCHIATRY 2016 DEC; 21(12):1648-1652
Murphy N, Falk RT, Messinger DB, Pollak M, Xue XN, Lin J, Sgueglia R, Strickler HD, Gaudet MM, Gunter MJ
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Influence of Fasting Status and Sample Preparation on Metabolic Biomarker Measurements in Postmenopausal Women

PLOS ONE 2016 DEC 8; 11(12):? Article e0167832
Background Epidemiologic data linking metabolic markers-such as insulin, insulin-like growth factors (IGFs)-and adipose tissue-derived factors with cancer are inconsistent. Between-study differences in blood collection protocols, in particular participant's fasting status, may influence measurements. Methods We investigated the impact of fasting status and blood sample processing time on components of the insulin/IGF axis and in adipokines in a controlled feeding study of 45 healthy postmenopausal-women aged 50-75 years. Fasting blood samples were drawn (T0), after which subjects ate a standardized breakfast; subsequent blood draws were made at 1 hour (T1), 3 hours (T3), and 6 hours (T6) after breakfast. Serum samples were assayed for insulin, C-peptide, total-and free-IGF-I, IGF-binding protein [BP]-1 and -3, total and high molecular weight (HMW)-adiponectin, retinol binding protein-4, plasminogen activator inhibitor (PAI)-1, and resistin. Results Insulin and C-peptide levels followed similar postprandial trajectories; intra-class correlation coefficients [ICC] for insulin = 0.75, (95% CI: 0.64-0.97) and C-peptide (ICC = 0.66, 95% CI: 0.54-0.77) were similarly correlated in fasting (Spearman correlation, r = 0.78, 95% CI: 0.64-0.88) and postprandial states (T1, r = 0.77 (95% CI: 0.62-0.87); T3, r = 0.78 (95% CI: 0.63-0.87); T6, r = 0.77 (95% CI: 0.61-0.87)). Free-IGF-I and IGFBP-1 levels were also affected by fasting status, whereas total-IGF-I and IGFBP-3 levels remained unchanged. Levels of adipokines were largely insensitive to fasting status and blood sample processing delays. Conclusion Several components of the insulin/IGF axis were significantly impacted by fasting state and in particular, C-peptide levels were substantially altered postprandially and in a similar manner to insulin.
El Azbaoui S, Sabri A, Ouraini S, Hassani A, Asermouh A, Agadr A, Abilkassem R, Dini N, Kmari M, Akhaddar A, Laktati Z, Aieche S, El Hafidi N, Ben Brahim F, Bousfiha AA, Ailal F, Deswarte C, Schurr E, Amar L, Bustamante J, Boisson-Dupuis S, Casanova JL, Abel L, El Baghdadi J
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Utility of the QuantiFERON((R))-TB Gold In-Tube assay for the diagnosis of tuberculosis in Moroccan children

INTERNATIONAL JOURNAL OF TUBERCULOSIS AND LUNG DISEASE 2016 DEC; 20(12):1639-1646
SETTING: The utility of interferon-gamma release assays (IGRAs), such as the QuantiFERON-TB Gold In-Tube (QFT-GIT) test, in diagnosing active tuberculosis (TB) in children is unclear and depends on the epidemiological setting. OBJECTIVE: To evaluate the performance of QFT-GIT for TB diagnosis in children living in Morocco, an intermediate TB incidence country with high bacille Calmette-Guerin vaccination coverage. DESIGN: We prospectively recruited 109 Moroccan children hospitalised for clinically suspected TB, all of whom were tested using QFT-GIT. RESULTS: For 81 of the 109 children, the final diagnosis was TB. The remaining 28 children did not have TB. QFT-GIT had a sensitivity of 66% (95%CI 52-77) for the diagnosis of TB, and a specificity of 100% (95%CI 88-100). The tuberculin skin test (TST) had lower sensitivity, at 46% (95%CI 33-60), and its concordance with QFT-GIT was limited (69%). Combining QFT-GIT and TST results increased sensitivity to 83% (95%CI 69-92). CONCLUSION: In epidemiological settings such as those found in Morocco, QFT-GIT is more sensitive than the TST for active TB diagnosis in children. Combining the TST and QFT-GIT would be useful for the diagnosis of active TB in children, in combination with clinical, radiological and laboratory data.
Estep CM, Galtieri DJ, Zampese E, Goldberg JA, Brichta L, Greengard P, Surmeier DJ
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Transient Activation of GABA(B) Receptors Suppresses SK Channel Currents in Substantia Nigra Pars Compacta Dopaminergic Neurons

PLOS ONE 2016 DEC 30; 11(12):? Article e0169044
Dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc) are richly innervated by GABAergic neurons. The postsynaptic effects of GABA on SNc DA neurons are mediated by a mixture of GABA(A) and GABA(B) receptors. Although activation of GABA(A) receptors inhibits spike generation, the consequences of GABA(B) receptor activation are less well characterized. To help fill this gap, perforated patch recordings were made from young adult mouse SNc DA neurons. Sustained stimulation of GABA(B) receptors hyperpolarized SNc DA neurons, as previously described. However, transient stimulation of GABA(B) receptors by optical uncaging of GABA did not; rather, it reduced the opening of small-conductance, calcium-activated K+ (SK) channels and increased the irregularity of spiking. This modulation was attributable to inhibition of adenylyl cyclase and protein kinase A. Thus, because suppression of SK channel activity increases the probability of burst spiking, transient co-activation of GABA(A) and GABA(B) receptors could promote a pause-burst pattern of spiking.
Song RJ, Pace C, Seaman MS, Fang Q, Sun M, Andrews CD, Wu A, Padte NN, Ho DD
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Distinct HIV-1 Neutralization Potency Profiles of Ibalizumab-Based Bispecific Antibodies

JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES 2016 DEC 1; 73(4):365-373
Background: Preexposure prophylaxis using antiretroviral agents has been shown to effectively prevent human immunodeficiency virus type 1 (HIV-1) acquisition in high-risk populations. However, the efficacy of these regimens is highly variable, which is thought to be largely due to the varying degrees of adherence to a daily intervention in the populations. Passive immunization using broadly neutralizing antibodies (bNAbs) against HIV-1, with their relatively long half-life and favorable safety profile, could provide an alternative to daily preexposure prophylaxis. However, most bNAbs have a limited breadth, only neutralizing 70%-90% of all HIV-1 strains. Methods: To overcome the problem of limited antiviral breadth, we proposed that targeting human CD4 and HIV-1 envelope proteins simultaneously may improve virus-neutralization breadth and potency. Therefore, we constructed bispecific antibodies (biAbs) using single-chain variable fragments of anti-gp120 bNAbs fused to ibalizumab (iMab), a humanized monoclonal antibody that binds human CD4, the primary receptor for HIV-1. Results: Some of our biAbs neutralized 100% of HIV-1 strains tested in vitro at clinically achievable concentrations. Distinct neutralization patterns were observed in this panel of biAbs. Those biAbs with specificity for the CD4-binding site on gp120 demonstrated 100% breadth, as well as slightly improved potency compared with iMab. In contrast, biAbs with specificity for the V1-V2 apex epitope or the V3-glycan epitope on gp120 demonstrated dramatically improved potency; some showed limited gain in neutralization breadth, whereas others (eg, PGT128-LM52 and 123-iMab) improved to 100% breadth. Conclusion: Our data suggest that this panel of iMab-based biAbs could be used to probe the parameters for potent HIV-1 neutralization. Moreover, a few of these biAbs warrant further studies and possibly clinical development.
Vucelja M
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Lifting-A nonreversible Markov chain Monte Carlo algorithm

AMERICAN JOURNAL OF PHYSICS 2016 DEC; 84(12):958-968
Markov chain Monte Carlo algorithms are invaluable tools for exploring stationary properties of physical systems, especially in situations where direct sampling is unfeasible. Common implementations of Monte Carlo algorithms employ reversible Markov chains. Reversible chains obey detailed balance and thus ensure that the system will eventually relax to equilibrium, though detailed balance is not necessary for convergence to equilibrium. We review nonreversible Markov chains, which violate detailed balance and yet still relax to a given target stationary distribution. In particular cases, nonreversible Markov chains are substantially better at sampling than the conventional reversible Markov chains with up to a square root improvement in the convergence time to the steady state. One kind of nonreversible Markov chain is constructed from the reversible ones by enlarging the state space and by modifying and adding extra transition rates to create non-reversible moves. Because of the augmentation of the state space, such chains are often referred to as lifted Markov Chains. We illustrate the use of lifted Markov chains for efficient sampling on several examples. The examples include sampling on a ring, sampling on a torus, the Ising model on a complete graph, and the one-dimensional Ising model. We also provide a pseudocode implementation, review related work, and discuss the applicability of such methods. (C) 2016 American Association of Physics Teachers.
Fernandez-Martinez J, Kim SJ, Shi Y, Upla P, Pellarin R, Gagnon M, Chemmama IE, Wang JJ, Nudelman I, Zhang WZ, Williams R, Rice WJ, Stokes DL, Zenklusen D, Chait BT, Sali A, Rout MP
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Structure and Function of the Nuclear Pore Complex Cytoplasmic mRNA Export Platform

CELL 2016 NOV 17; 167(5):1215-1228
The last steps in mRNA export and remodeling are performed by the Nup82 complex, a large conserved assembly at the cytoplasmic face of the nuclear pore complex (NPC). By integrating diverse structural data, we have determined the molecular architecture of the native Nup82 complex at subnanometer precision. The complex consists of two compositionally identical multiprotein subunits that adopt different configurations. The Nup82 complex fits into the NPC through the outer ring Nup84 complex. Our map shows that this entire 14-MDa Nup82-Nup84 complex assembly positions the cytoplasmic mRNA export factor docking sites and messenger ribonucleoprotein (mRNP) remodeling machinery right over the NPC's central channel rather than on distal cytoplasmic filaments, as previously supposed. We suggest that this configuration efficiently captures and remodels exporting mRNP particles immediately upon reaching the cytoplasmic side of the NPC.