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Shaheen A, Tariq A, Iqbal M, Mirza O, Haque A, Walz T, Rahman M
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Mutational Diversity in the Quinolone Resistance-Determining Regions of Type-II Topoisomerases of Salmonella Serovars

ANTIBIOTICS-BASEL 2021 DEC; 10(12):? Article 1455
Quinolone resistance in bacterial pathogens has primarily been associated with mutations in the quinolone resistance-determining regions (QRDRs) of bacterial type-II topoisomerases, which are DNA gyrase and topoisomerase IV. Depending on the position and type of the mutation (s) in the QRDRs, bacteria either become partially or completely resistant to quinolone. QRDR mutations have been identified and characterized in Salmonella enterica isolates from around the globe, particularly during the last decade, and efforts have been made to understand the propensity of different serovars to carry such mutations. Because there is currently no thorough analysis of the available literature on QRDR mutations in different Salmonella serovars, this review aims to provide a comprehensive picture of the mutational diversity in QRDRs of Salmonella serovars, summarizing the literature related to both typhoidal and non-typhoidal Salmonella serovars with a special emphasis on recent findings. This review will also discuss plasmid-mediated quinolone-resistance determinants with respect to their additive or synergistic contributions with QRDR mutations in imparting elevated quinolone resistance. Finally, the review will assess the contribution of membrane transporter-mediated quinolone efflux to quinolone resistance in strains carrying QRDR mutations. This information should be helpful to guide the routine surveillance of foodborne Salmonella serovars, especially with respect to their spread across countries, as well as to improve laboratory diagnosis of quinolone-resistant Salmonella strains.
Beziat V, Casanova JL, Jouanguy E
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Human genetic and immunological dissection of papillomavirus-driven diseases: new insights into their pathogenesis

CURRENT OPINION IN VIROLOGY 2021 DEC; 51:9-15
Human papillomaviruses (HPVs) are responsible for cutaneous and mucosal lesions. Persistent HPV infection remains a leading cause of uterine cancer in women, but also of cutaneous squamous cell carcinoma in patients with epidermodysplasia verruciformis (EV), and of rare and devastating benign tumors, such as 'tree-man' syndrome. HPV infections are usually asymptomatic or benign in the general population. Severe manifestations in otherwise healthy subjects can attest to inherited immunodeficiencies. The human genetic dissection of these cases has identified critical components of the immune response to HPVs, including the non-redundant roles of keratinocyte-intrinsic immunity in controlling 13-HPVs, and of T cell-dependent adaptive immunity for controlling all HPV types. A key role of the CD28 T-cell costimulation pathway in controlling common warts due to HPVs was recently discovered. This review summarizes the state of the art in the human genetics of HPV infection, focusing on two key affected cell types: keratinocytes and T cells.
Mueller RC, Ellstrom P, Howe K, Uliano-Silva M, Kuo RI, Miedzinska K, Warr A, Fedrigo O, Haase B, Mountcastle J, Chow W, Torrance J, Wood JMD, Jarhult JD, Naguib MM, Olsen B, Jarvis ED, Smith J, Eory L, Kraus RHS
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A high-quality genome and comparison of short-versus long -read transcriptome of the palaearctic duck Aythya fuligula (tufted duck)

GIGASCIENCE 2021 DEC; 10(12):? Article giab081
Background: The tufted duck is a non-model organism that experiences high mortality in highly pathogenic avian influenza outbreaks. It belongs to the same bird family (Anatidae) as the mallard, one of the best-studied natural hosts of low-pathogenic avian influenza viruses. Studies in non-model bird species are crucial to disentangle the role of the host response in avian influenza virus infection in the natural reservoir. Such endeavour requires a high-quality genome assembly and transcriptome. Findings: This study presents the first high-quality, chromosome-level reference genome assembly of the tufted duck using the Vertebrate Genomes Project pipeline. We sequenced RNA (complementary DNA) from brain, ileum, lung, ovary, spleen, and testis using Illumina short-read and Pacific Biosciences long-read sequencing platforms, which were used for annotation. We found 34 autosomes plus Z and W sex chromosomes in the curated genome assembly, with 99.6% of the sequence assigned to chromosomes. Functional annotation revealed 14,099 protein-coding genes that generate 111,934 transcripts, which implies a mean of 7.9 isoforms per gene. We also identified 246 small RNA families. Conclusions: This annotated genome contributes to continuing research into the host response in avian influenza virus infections in a natural reservoir. Our findings from a comparison between short-read and long -read reference transcriptomics contribute to a deeper understanding of these competing options. In this study, both technologies complemented each other. We expect this annotation to be a foundation for further comparative and evolutionary genomic studies, including many waterfowl relatives with differing susceptibilities to avian influenza viruses.
Parthasarathy R, Hagglof T, Hadley JT, McLennan A, Mattke A, Dudley EA, Kumagai A, Dong LLQ, Leadbetter EA
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Receptor Interacting Protein Kinase Pathways Regulate Innate B Cell Developmental Checkpoints But Not Effector Function in Mice

FRONTIERS IN IMMUNOLOGY 2021 DEC 9; 12(?):? Article 758407
Mutations in the scaffolding domain of Receptor Interacting Protein kinases (RIP) underlie the recently described human autoimmune syndrome, CRIA, characterized by lymphadenopathy, splenomegaly, and autoantibody production. While disease mechanisms for CRIA remain undescribed, RIP kinases work together with caspase-8 to regulate cell death, which is critical for normal differentiation of many cell types. Here, we describe a key role for RIP1 in facilitating innate B cell differentiation and subsequent activation. By comparing RIP1, RIP3, and caspase-8 triple deficient and RIP3, caspase-8 double deficient mice, we identified selective contributions of RIP1 to an accumulation of murine splenic Marginal Zone (MZ) B cells and B1-b cells. We used mixed bone-marrow chimeras to determine that innate B cell commitment required B cell-intrinsic RIP1, RIP3, and caspase-8 sufficiency. RIP1 regulated MZ B cell development rather than differentiation and RIP1 mediates its innate immune effects independent of the RIP1 kinase domain. NP-KLH/alum and NP-Ficoll vaccination of mice doubly deficient in both caspase-8 and RIP3 or deficient in all three proteins (RIP3, caspase-8, and RIP1) revealed uniquely delayed T-dependent and T-independent IgG responses, abnormal splenic germinal center architecture, and reduced extrafollicular plasmablast formation compared to WT mice. Thus, RIP kinases and caspase-8 jointly orchestrate B cell fate and delayed effector function through a B cell-intrinsic mechanism.
Prakash R, Freyer L, Saiz N, Gavrilov S, Wang RQ, Romanienko PJ, Lacy E, Hadjantonakis AK, Jasin M
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XRCC3 loss leads to midgestational embryonic lethality in mice

DNA REPAIR 2021 DEC; 108 Article 103227
RAD51 paralogs are key components of the homologous recombination (HR) machinery. Mouse mutants have been reported for four of the canonical RAD51 paralogs, and each of these mutants exhibits embryonic lethality, although at different gestational stages. However, the phenotype of mice deficient in the fifth RAD51 paralog, XRCC3, has not been reported. Here we report that Xrcc3 knockout mice exhibit midgestational lethality, with mild phenotypes beginning at about E8.25 but severe developmental abnormalities evident by E9.0-9.5. The most obvious phenotypes are small size and a failure of the embryo to turn to a fetal position. A knockin mutation at a key ATPase residue in the Walker A box results in embryonic lethality at a similar stage. Death of knockout mice can be delayed a few days for some embryos by homozygous or heterozygous Trp53 mutation, in keeping with an important role for XRCC3 in promoting genome integrity. Given that XRCC3 is a unique member of one of two RAD51 paralog complexes with RAD51C, these results demonstrate that both RAD51 paralog complexes are required for mouse development.
Chen XQ, Barrero CA, Carpio RVD, Reddy EP, Fecchio C, Merali S, Deglincerti A, Fang C, Rogers J, Maccecchini ML
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Posiphen Reduces the Levels of Huntingtin Protein through Translation Suppression

PHARMACEUTICS 2021 DEC; 13(12):? Article 2109
Posiphen tartrate (Posiphen) is an orally available small molecule that targets a conserved regulatory element in the mRNAs of amyloid precursor protein (APP) and alpha-synuclein (alpha SYN) and inhibits their translation. APP and alpha SYN can cause neurodegeneration when their aggregates induce neurotoxicity. Therefore, Posiphen is a promising drug candidate for neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Posiphen's safety has been demonstrated in three independent phase I clinical trials. Moreover, in a proof of concept study, Posiphen lowered neurotoxic proteins and inflammatory markers in cerebrospinal fluid of mild cognitive impaired patients. Herein we investigated whether Posiphen reduced the expression of other proteins, as assessed by stable isotope labeling with amino acids in cell culture (SILAC) followed by mass spectrometry (MS)-based proteomics. Neuroblastoma SH-SY5Y cells, an in vitro model of neuronal function, were used for the SILAC protein profiling response. Proteins whose expression was altered by Posiphen treatment were characterized for biological functions, pathways and networks analysis. The most significantly affected pathway was the Huntington's disease signaling pathway, which, along with huntingtin (HTT) protein, was down-regulated by Posiphen in the SH-SY5Y cells. The downregulation of HTT protein by Posiphen was confirmed by quantitative Western blotting and immunofluorescence. Unchanged mRNA levels of HTT and a comparable decay rate of HTT proteins after Posiphen treatment supported the coclusion that Posiphen reduced HTT via downregulation of the translation of HTT mRNA. Meanwhile, the downregulation of APP and alpha SYN proteins by Posiphen was also confirmed. The mRNAs encoding HTT, APP and alpha SYN contain an atypical iron response element (IRE) in their 5 '-untranslated regions (5 '-UTRs) that bind iron regulatory protein 1 (IRP1), and Posiphen specifically bound this complex. Conversely, Posiphen did not bind the IRP1/IRE complex of mRNAs with canonical IREs, and the translation of these mRNAs was not affected by Posiphen. Taken together, Posiphen shows high affinity binding to the IRE/IRP1 complex of mRNAs with an atypical IRE stem loop, inducing their translation suppression, including the mRNAs of neurotoxic proteins APP, alpha SYN and HTT.
Thakkar PV, Kita K, Del Castillo U, Galletti G, Madhukar N, Navarro EV, Barasoain I, Goodson HV, Sackett D, Diaz JF, Lu Y, RoyChoudhury A, Molina H, Elemento O, Shah MA, Giannakakou P
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CLIP-170S is a microtubule plus TIP variant that confers resistance to taxanes by impairing drug-target engagement

DEVELOPMENTAL CELL 2021 DEC 6; 56(23):3264-+
Taxanes are widely used cancer chemotherapeutics. However, intrinsic resistance limits their efficacy without any actionable resistance mechanism. We have discovered a microtubule (MT) plus-end-binding CLIP-170 protein variant, hereafter CLIP-170S, which we found enriched in taxane-resistant cell lines and patient samples. CLIP-170S lacks the first Cap-Gly motif, forms longer comets, and impairs taxane access to its MT luminal binding site. CLIP-170S knockdown reversed taxane resistance in cells and xenografts, whereas its re-expression led to resistance, suggesting causation. Using a computational approach in conjunction with the connectivity map, we unexpectedly discovered that Imatinib was predicted to reverse CLIP-170S mediated taxane resistance. Indeed, Imatinib treatment selectively depleted CLIP-170S, thus completely reversing taxane resistance. Other RTK inhibitors also depleted CLIP-170S, suggesting a class effect. Herein, we identify CLIP-170S as a clinically prevalent variant that confers taxane resistance, whereas the discovery of Imatinib as a CLIP-170S inhibitor provides novel therapeutic opportunities for future trials.
Arkin LM, Moon JJ, Tran JM, Asgan S, O'Farrelly C, Casanova JL, Cowen EW, Mays JW, Singh AM, Drolet BA
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From Your Nose to Your Toes: A Review of Severe Acute Respiratory Syndrome Coronavirus 2 Pandemic-Associated Pernio

JOURNAL OF INVESTIGATIVE DERMATOLOGY 2021 DEC; 141(12):2791-2796
Despite thousands of reported patients with pandemic-associated pernio, low rates of seroconversion and PCR positivity have defied causative linkage to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pernio in uninfected children is associated with monogenic disorders of excessive IFN-1 immunity, whereas severe COVID-19 pneumonia can result from insufficient IFN-1. Moreover, SARS-CoV-2 spike protein and robust IFN-1 response are seen in the skin of patients with pandemicassociated pernio, suggesting an excessive innate immune skin response to SARS-CoV-2. Understanding the pathophysiology of this phenomenon may elucidate the host mechanisms that drive a resilient immune response to SARS-CoV-2 and could produce relevant therapeutic targets.
Abt I, Aggarwal R, Aushev V, Behnke O, Bertolin A, Bloch I, Brock I, Brook NH, Brugnera R, Bruni A, Bussey PJ, Caldwell A, Catterall CD, Chwastowski J, Ciborowski J, Ciesielski R, Cooper-Sarkar AM, Corradi M, Dementiev RK, Dusini S, Ferrando J, Floerchinger S, Foster B, Gallo E, Gangadharan D, Garfagnini A, Geiser A, Gladilin LK, Golubkov YA, Grzelak G, Gwenlan C, Hochman D, Jomhari NZ, Kadenko I, Karshon U, Kaur P, Klanner R, Klein U, Korzhavina IA, Kovalchuk N, Kuze M, Levchenko BB, Levy A, Lohr B, Lohrmann E, Longhin A, Lorkowski F, Lukina OY, Makarenko I, Malka J, Masciocchi S, Nagano K, Nam JD, Onderwaater J, Onishchuk Y, Paul E, Pidhurskyi I, Polini A, Przybycien M, Quintero A, Ruspa M, Schneekloth U, Schorner-Sadenius T, Selyuzhenkov I, Shchedrolosiev M, Shcheglova LM, Skillicorn IO, Slominski W, Solano A, Stanco L, Stefaniuk N, Surrow B, Tokushuku K, Turkot O, Tymieniecka T, Verbytskyi A, Abdullah WATW, Wichmann K, Wing M, Yamada S, Yamazaki Y, Zarnecki AF, Zenaiev O
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Azimuthal correlations in photoproduction and deep inelastic ep scattering at HERA

JOURNAL OF HIGH ENERGY PHYSICS 2021 DEC 16; ?(12):? Article 102
Collective behaviour of final-state hadrons, and multiparton interactions are studied in high-multiplicity ep scattering at a centre-of-mass energy root s = 318 GeV with the ZEUS detector at HERA. Two- and four-particle azimuthal correlations, as well as multiplicity, transverse momentum, and pseudorapidity distributions for charged-particle multiplicities N-ch >= 20 are measured. The dependence of two-particle correlations on the virtuality of the exchanged photon shows a clear transition from photoproduction to neutral current deep inelastic scattering. For the multiplicities studied, neither the measurements in photoproduction processes nor those in neutral current deep inelastic scattering indicate significant collective behaviour of the kind observed in high-multiplicity hadronic collisions at RHIC and the LHC. Comparisons of PYTHIA predictions with the measurements in photoproduction strongly indicate the presence of multiparton interactions from hadronic fluctuations of the exchanged photon.
Martinot M, Korganow AS, Wald M, Second J, Birckel E, Mahe A, Souply L, Mohseni-Zadeh M, Droy L, Tarabeux J, Okada S, Migaud M, Puel A, Guffroy A
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Case Report: A New Gain-of-Function Mutation of STAT1 Identified in a Patient With Chronic Mucocutaneous Candidiasis and Rosacea-Like Demodicosis: An Emerging Association

FRONTIERS IN IMMUNOLOGY 2021 DEC 20; 12(?):? Article 760019
PurposeHeterozygous missense STAT1 mutations leading to a gain of function (GOF) are the most frequent genetic cause of chronic mucocutaneous candidiasis (CMC). We describe the case of a patient presenting a new GOF mutation of STAT1 with the clinical symptoms of CMC, recurrent pneumonia, and persistent central erythema with papulopustules with ocular involvement related to rosacea-like demodicosis. MethodsGenetic analysis via targeted next-generation sequencing (NGS; NGS panel DIPAI v.1) exploring the 98 genes most frequently involved in primary immunodeficiencies, including STAT1, was performed to identify an underlying genetic defect. ResultsNGS identified a novel variant of STAT1, c.884C>A (exon 10), p.T295Y, not previously described. This variant was found to be gain of function using an in vitro luciferase reporter assay. Rosacea-like demodicosis was confirmed by substantial Demodex proliferation observed via the microscopic examination of a cutaneous sample. A review of literature retrieved 20 other cases of STAT1 GOF mutations associated with early-onset rosacea-like demodicosis, most with ocular involvement. ConclusionWe describe a new STAT1 GOF mutation associated with a phenotype of CMC and rosacea-like demodicosis. Rosacea-like demodicosis appears as a novel and important clinical phenotype among patients with STAT1 GOF mutation.