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Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, ...
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Measurement of boosted Higgs bosons produced via vector boson fusion or gluon... (opens in new window)

JOURNAL OF HIGH ENERGY PHYSICS 2024 DEC 4; ?(12):? Article 035
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A measurement is performed of Higgs bosons produced with high transverse momentum (p(T)) via vector boson or gluon fusion in proton-proton collisions. The result is based on a data set with a center-of-mass energy of 13 TeV collected in 2016-2018 with the CMS detector at the LHC and corresponds to an integrated luminosity of 138 fb(-1). The decay of a high-p(T) Higgs boson to a boosted bottom quark-antiquark pair is selected using large-radius jets and employing jet substructure and heavy-flavor taggers based on machine learning techniques. Independent regions targeting the vector boson and gluon fusion mechanisms are defined based on the topology of two quark-initiated jets with large pseudorapidity separation. The signal strengths for both processes are extracted simultaneously by performing a maximum likelihood fit to data in the large-radius jet mass distribution. The observed signal strengths relative to the standard model expectation are 4.9(-1.6)(+1.9) and 1.6(-1.5)(+1.7) for the vector boson and gluon fusion mechanisms, respectively. A differential cross section measurement is also reported in the simplified template cross section framework.
Mayle R, Holloman WK, O'Donnell ME
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DNA polymerase z has robust reverse transcriptase activity relative to other ... (opens in new window)

JOURNAL OF BIOLOGICAL CHEMISTRY 2024 DEC; 300(12):? Article 107918
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Cell biology and genetic studies have demonstrated that DNA double-strand break (DSB) repair can be performed using an RNA transcript that spans the site of the DNA break as a template for repair. This type of DSB repair requires a reverse transcriptase to convert an RNA sequence into DNA to facilitate repair of the break, rather than copying from a DNA template as in canonical DSB repair. Translesion synthesis (TLS) DNA polymerases (Pol) are often more promiscuous than DNA Pols, raising the notion that reverse transcription could be performed by a TLS Pol. Indeed, several studies have demonstrated that human Pol h has reverse transcriptase activity, while others have suggested that the yeast TLS Polz is involved. Here, we purify all seven known nuclear DNA Pols of Saccharomyces cerevisiae and compare their reverse transcriptase activities. The comparison shows that Polz far surpasses Pol h and all other DNA Pols in reverse transcriptase activity. We fi nd that Polz reverse transcriptase activity is not affected by RPA or RFC/PCNA and acts distributively to make DNA complementary to an RNA template strand. Consistent with prior S. cerevisiae studies performed in vivo, we propose that Polz is the major DNA Pol that functions in the RNAtemplated DSB repair pathway.
Frickmann H, Sarfo FS, Norman BR, Dompreh A, Asibey SO, Boateng R, Kuffour EO...
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Association of Molecular Detections of Microsporidia in Stool Samples with Cl... (opens in new window)

PATHOGENS 2024 DEC; 13(12):? Article 1053
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Although the etiological relevance of the detection of microsporidia in human stool samples remains uncertain, the immunological status of patients has been posited as an important determinant of potential clinical impact of these parasites. To further assess the interplay between the epidemiology of microsporidia and immunological markers, we conducted a study utilizing real-time PCR targeting Enterocytozoon bieneusi, Encephalitozoon cuniculi, Encephalitozoon hellem, and Encephalitozoon intestinalis, combined in a single fluorescence channel. The study involved a cohort of 595 clinically and immunologically well-characterized Ghanaian HIV patients, alongside 82 HIV-negative control individuals from Ghana. While microsporidial DNA was absent in HIV-negative controls, among people living with HIV, its prevalence was inversely correlated with CD4+ lymphocyte counts: 6.0% in those with >500 cells/mu L, 9.5% in those with 200-499 cells/mu L, 13.8% in those with 50-199 cells/mu L, and 27.5% in those with <50 cells/L, respectively. Correspondingly, microsporidia were more frequently detected in HIV patients who were not receiving antiretroviral therapy. There were no associations with clinical symptoms including gastroenteritis with the exception of a non-significant trend towards weight loss. HLA-DR+CD38+ on CD4+ T lymphocytes, a marker of immune activation, as well as Ki67, a marker of cell proliferation, were increased on CD4+ T lymphocytes in HIV patients with microsporidia, suggesting an immune response may be triggered. In conclusion, our assessment indicates a higher prevalence of microsporidia in the stool of Ghanaian HIV patients, which varies with their immunological status. However, given the lack of clear associations with clinical symptoms, the detection of microsporidia in the stool of HIV patients needs to be cautiously interpreted in clinical settings.
Chen YJ, Iyer SV, Hsieh DCC, Li BR, Elias HK, Wang T, Li J, Ganbold M, Lien M...
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Gliocidin is a nicotinamide-mimetic prodrug that targets glioblastoma (opens in new window)

NATURE 2024 DEC 12; 636(8042):466-+
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Glioblastoma is incurable and in urgent need of improved therapeutics(1). Here we identify a small compound, gliocidin, that kills glioblastoma cells while sparing non-tumour replicative cells. Gliocidin activity targets a de novo purine synthesis vulnerability in glioblastoma through indirect inhibition of inosine monophosphate dehydrogenase 2 (IMPDH2). IMPDH2 blockade reduces intracellular guanine nucleotide levels, causing nucleotide imbalance, replication stress and tumour cell death(2). Gliocidin is a prodrug that is anabolized into its tumoricidal metabolite, gliocidin-adenine dinucleotide (GAD), by the enzyme nicotinamide nucleotide adenylyltransferase 1 (NMNAT1) of the NAD(+) salvage pathway. The cryo-electron microscopy structure of GAD together with IMPDH2 demonstrates its entry, deformation and blockade of the NAD(+) pocket(3). In vivo, gliocidin penetrates the blood-brain barrier and extends the survival of mice with orthotopic glioblastoma. The DNA alkylating agent temozolomide induces Nmnat1 expression, causing synergistic tumour cell killing and additional survival benefit in orthotopic patient-derived xenograft models. This study brings gliocidin to light as a prodrug with the potential to improve the survival of patients with glioblastoma.
Coleman RT, Morantte I, Koreman GT, Cheng ML, Ding Y, Ruta V
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A modular circuit coordinates the diversification of courtship strategies (opens in new window)

NATURE 2024 NOV 7; 635(8037):?
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Mate recognition systems evolve rapidly to reinforce the reproductive boundaries between species, but the underlying neural mechanisms remain enigmatic. Here we leveraged the rapid coevolution of female pheromone production and male pheromone perception in Drosophila1,2 to gain insight into how the architecture of mate recognition circuits facilitates their diversification. While in some Drosophila species females produce unique pheromones that act to arouse their conspecific males, the pheromones of most species are sexually monomorphic such that females possess no distinguishing chemosensory signatures that males can use for mate recognition3. We show that Drosophila yakuba males evolved the ability to use a sexually monomorphic pheromone, 7-tricosene, as an excitatory cue to promote courtship. By comparing key nodes in the pheromone circuits across multiple Drosophila species, we reveal that this sensory innovation arises from coordinated peripheral and central circuit adaptations: a distinct subpopulation of sensory neurons has acquired sensitivity to 7-tricosene and, in turn, selectively signals to a distinct subset of P1 neurons in the central brain to trigger courtship. Such a modular circuit organization, in which different sensory inputs can independently couple to parallel courtship control nodes, may facilitate the evolution of mate recognition systems by allowing novel sensory modalities to become linked to male arousal. Together, our findings suggest how peripheral and central circuit adaptations can be flexibly coordinated to underlie the rapid evolution of mate recognition strategies across species. Peripheral and central circuit adaptations can be flexibly coordinated in Drosophila, and such a modular circuit organization may facilitate the evolution of mate recognition systems by allowing novel sensory modalities to become linked to male arousal.
De Faveri C, Mattheisen JM, Sakmar TP, Coin I
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Noncanonical Amino Acid Tools and Their Application to Membrane Protein Studi... (opens in new window)

CHEMICAL REVIEWS 2024 NOV 7; 124(22):12498-12550
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Methods rooted in chemical biology have contributed significantly to studies of integral membrane proteins. One recent key approach has been the application of genetic code expansion (GCE), which enables the site-specific incorporation of noncanonical amino acids (ncAAs) with defined chemical properties into proteins. Efficient GCE is challenging, especially for membrane proteins, which have specialized biogenesis and cell trafficking machinery and tend to be expressed at low levels in cell membranes. Many eukaryotic membrane proteins cannot be expressed functionally in E. coli and are most effectively studied in mammalian cell culture systems. Recent advances have facilitated broader applications of GCE for studies of membrane proteins. First, AARS/tRNA pairs have been engineered to function efficiently in mammalian cells. Second, bioorthogonal chemical reactions, including cell-friendly copper-free "click" chemistry, have enabled linkage of small-molecule probes such as fluorophores to membrane proteins in live cells. Finally, in concert with advances in GCE methodology, the variety of available ncAAs has increased dramatically, thus enabling the investigation of protein structure and dynamics by multidisciplinary biochemical and biophysical approaches. These developments are reviewed in the historical framework of the development of GCE technology with a focus on applications to studies of membrane proteins.
Zhang SY, Casanova JL
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Genetic defects of brain immunity in childhood herpes simplex encephalitis (opens in new window)

NATURE 2024 NOV 21; 635(8039):563-573
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Herpes simplex virus 1 (HSV-1) encephalitis (HSE) is the most common sporadic viral encephalitis in humans. It is life-threatening and has a first peak of incidence in childhood, during primary infection. Children with HSE are not particularly prone to other infections, including HSV-1 infections of tissues other than the brain. About 8-10% of childhood cases are due to monogenic inborn errors of 19 genes, two-thirds of which are recessive, and most of which display incomplete clinical penetrance. Childhood HSE can therefore be sporadic but genetic, enabling new diagnostic and therapeutic approaches. In this Review, we examine essential cellular and molecular mechanisms of cell-intrinsic antiviral immunity in the brain that are disrupted in individuals with HSE. These mechanisms include both known (such as mutations in the TLR3 pathway) and previously unknown (such as the TMEFF1 restriction factor) antiviral pathways, which may be dependent (for example, IFNAR1) or independent (for example, through RIPK3) of type I interferons. They operate in cortical or brainstem neurons, and underlie forebrain and brainstem infections, respectively. Conversely, the most severe inborn errors of leukocytes, including a complete lack of myeloid and/or lymphoid blood cells, do not underlie HSE. Thus congenital defects in intrinsic immunity in brain-resident neurons that underlie HSE broaden natural host defences against HSV-1 from the leukocytes of the immune system to other cells in the organism. This article reviews evidence that has emerged over the past two decades indicating that herpes simplex encephalitis in children can result from monogenic defects of brain immunity to herpes simplex virus 1.
Capili B, Anastasi JK
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An Introduction to Types of Quasi-Experimental Designs (opens in new window)

AMERICAN JOURNAL OF NURSING 2024 NOV; 124(11):50-52
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Hyun K, Ahn J, Kim H, Kim J, Kim YI, Park HS, Roeder RG, Lee JE, Kim J
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The BAF complex enhances transcription through interaction with H3K56ac in th... (opens in new window)

NATURE COMMUNICATIONS 2024 NOV 7; 15(1):? Article 9614
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Histone post-translational modifications play pivotal roles in eukaryotic gene expression. To date, most studies have focused on modifications in unstructured histone N-terminal tail domains and their binding proteins. However, transcriptional regulation by chromatin-effector proteins that directly recognize modifications in histone globular domains has yet to be clearly demonstrated, despite the richness of their multiple modifications. Here, we show that the ATP-dependent chromatin-remodeling BAF complex stimulates p53-dependent transcription through direct interaction with H3K56ac located on the lateral surface of the histone globular domain. Mechanistically, the BAF complex recognizes nucleosomal H3K56ac via the DPF domain in the DPF2 subunit and exhibits enhanced nucleosome-remodeling activity in the presence of H3K56ac. We further demonstrate that a defect in H3K56ac-BAF complex interaction leads to impaired p53-dependent gene expression and DNA damage responses. Our study provides direct evidence that histone globular domain modifications participate in the regulation of gene expression. The authors suggest that histone globular domain modifications participate in the regulation of gene expression. The ATP-dependent chromatin-remodeling BAF complex enhances transcription through direct interaction with H3K56ac located on the lateral surface of the histone globular domain.
Rosain J, Le Voyer T, Liu X, Gervais A, Polivka L, Cederholm A, Berteloot L, ...
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Incontinentia pigmenti underlies thymic dysplasia, autoantibodies to type I I... (opens in new window)

JOURNAL OF EXPERIMENTAL MEDICINE 2024 NOV 4; 221(11):? Article e20231152
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Human inborn errors of thymic T cell tolerance underlie the production of autoantibodies (auto-Abs) neutralizing type I IFNs, which predispose to severe viral diseases. We analyze 131 female patients with X-linked dominant incontinentia pigmenti (IP), heterozygous for loss-of-function (LOF) NEMO variants, from 99 kindreds in 10 countries. Forty-seven of these patients (36%) have auto-Abs neutralizing IFN-alpha and/or IFN-omega, a proportion 23 times higher than that for age-matched female controls. This proportion remains stable from the age of 6 years onward. On imaging, female patients with IP have a small, abnormally structured thymus. Auto-Abs against type I IFNs confer a predisposition to life-threatening viral diseases. By contrast, patients with IP lacking auto-Abs against type I IFNs are at no particular risk of viral disease. These results suggest that IP accelerates thymic involution, thereby underlying the production of auto-Abs neutralizing type I IFNs in at least a third of female patients with IP, predisposing them to life-threatening viral diseases.