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1.
Nat Immunol ; 21(8): 857-867, 2020 08.
Article in English | MEDLINE | ID: mdl-32601469

ABSTRACT

Familial Mediterranean fever (FMF) is an autoinflammatory disease caused by homozygous or compound heterozygous gain-of-function mutations in MEFV, which encodes pyrin, an inflammasome protein. Heterozygous carrier frequencies for multiple MEFV mutations are high in several Mediterranean populations, suggesting that they confer selective advantage. Among 2,313 Turkish people, we found extended haplotype homozygosity flanking FMF-associated mutations, indicating evolutionarily recent positive selection of FMF-associated mutations. Two pathogenic pyrin variants independently arose >1,800 years ago. Mutant pyrin interacts less avidly with Yersinia pestis virulence factor YopM than with wild-type human pyrin, thereby attenuating YopM-induced interleukin (IL)-1ß suppression. Relative to healthy controls, leukocytes from patients with FMF harboring homozygous or compound heterozygous mutations and from asymptomatic heterozygous carriers released heightened IL-1ß specifically in response to Y. pestis. Y. pestis-infected MefvM680I/M680I FMF knock-in mice exhibited IL-1-dependent increased survival relative to wild-type knock-in mice. Thus, FMF mutations that were positively selected in Mediterranean populations confer heightened resistance to Y. pestis.


Subject(s)
Disease Resistance/genetics , Familial Mediterranean Fever/genetics , Plague , Pyrin/genetics , Selection, Genetic/genetics , Animals , Bacterial Outer Membrane Proteins/immunology , Bacterial Outer Membrane Proteins/metabolism , Disease Resistance/immunology , Haplotypes , Humans , Inflammasomes/immunology , Inflammasomes/metabolism , Mice , Mice, Inbred C57BL , Mutation , Plague/immunology , Plague/metabolism , Pyrin/immunology , Pyrin/metabolism , Turkey , Virulence Factors/immunology , Virulence Factors/metabolism , Yersinia pestis
2.
Cell ; 166(2): 328-342, 2016 Jul 14.
Article in English | MEDLINE | ID: mdl-27374332

ABSTRACT

Metastases are the main cause of cancer deaths, but the mechanisms underlying metastatic progression remain poorly understood. We isolated pure populations of cancer cells from primary tumors and metastases from a genetically engineered mouse model of human small cell lung cancer (SCLC) to investigate the mechanisms that drive the metastatic spread of this lethal cancer. Genome-wide characterization of chromatin accessibility revealed the opening of large numbers of distal regulatory elements across the genome during metastatic progression. These changes correlate with copy number amplification of the Nfib locus, and differentially accessible sites were highly enriched for Nfib transcription factor binding sites. Nfib is necessary and sufficient to increase chromatin accessibility at a large subset of the intergenic regions. Nfib promotes pro-metastatic neuronal gene expression programs and drives the metastatic ability of SCLC cells. The identification of widespread chromatin changes during SCLC progression reveals an unexpected global reprogramming during metastatic progression.


Subject(s)
Lung Neoplasms/pathology , NFI Transcription Factors/metabolism , Neoplasm Metastasis/pathology , Small Cell Lung Carcinoma/pathology , Amino Acid Motifs , Animals , Cell Line, Tumor , Cells, Cultured , Disease Models, Animal , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Mice , NFI Transcription Factors/genetics , Promoter Regions, Genetic , Small Cell Lung Carcinoma/genetics , Small Cell Lung Carcinoma/metabolism , Up-Regulation
3.
Immunity ; 54(11): 2632-2649.e6, 2021 11 09.
Article in English | MEDLINE | ID: mdl-34715018

ABSTRACT

The incidence and severity of sepsis is higher among individuals of African versus European ancestry. We found that genetic risk variants (RVs) in the trypanolytic factor apolipoprotein L1 (APOL1), present only in individuals of African ancestry, were associated with increased sepsis incidence and severity. Serum APOL1 levels correlated with sepsis and COVID-19 severity, and single-cell sequencing in human kidneys revealed high expression of APOL1 in endothelial cells. Analysis of mice with endothelial-specific expression of RV APOL1 and in vitro studies demonstrated that RV APOL1 interfered with mitophagy, leading to cytosolic release of mitochondrial DNA and activation of the inflammasome (NLRP3) and the cytosolic nucleotide sensing pathways (STING). Genetic deletion or pharmacological inhibition of NLRP3 and STING protected mice from RV APOL1-induced permeability defects and proinflammatory endothelial changes in sepsis. Our studies identify the inflammasome and STING pathways as potential targets to reduce APOL1-associated health disparities in sepsis and COVID-19.


Subject(s)
Apolipoprotein L1/genetics , Black People/genetics , COVID-19/genetics , Genetic Predisposition to Disease/genetics , Sepsis/genetics , Animals , Apolipoprotein L1/blood , Black People/statistics & numerical data , COVID-19/pathology , DNA, Mitochondrial/metabolism , Endothelial Cells/metabolism , Humans , Inflammation/genetics , Inflammation/pathology , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Knockout , Mitophagy/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Risk Factors , Sepsis/pathology , Severity of Illness Index , White People/genetics , White People/statistics & numerical data
4.
Genes Dev ; 35(15-16): 1109-1122, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34301766

ABSTRACT

Lung adenocarcinoma, the most prevalent lung cancer subtype, is characterized by its high propensity to metastasize. Despite the importance of metastasis in lung cancer mortality, its underlying cellular and molecular mechanisms remain largely elusive. Here, we identified miR-200 miRNAs as potent suppressors for lung adenocarcinoma metastasis. miR-200 expression is specifically repressed in mouse metastatic lung adenocarcinomas, and miR-200 decrease strongly correlates with poor patient survival. Consistently, deletion of mir-200c/141 in the KrasLSL-G12D/+ ; Trp53flox/flox lung adenocarcinoma mouse model significantly promoted metastasis, generating a desmoplastic tumor stroma highly reminiscent of metastatic human lung cancer. miR-200 deficiency in lung cancer cells promotes the proliferation and activation of adjacent cancer-associated fibroblasts (CAFs), which in turn elevates the metastatic potential of cancer cells. miR-200 regulates the functional interaction between cancer cells and CAFs, at least in part, by targeting Notch ligand Jagged1 and Jagged2 in cancer cells and inducing Notch activation in adjacent CAFs. Hence, the interaction between cancer cells and CAFs constitutes an essential mechanism to promote metastatic potential.


Subject(s)
Cancer-Associated Fibroblasts , Lung Neoplasms , MicroRNAs , Animals , Cell Line, Tumor , Cell Proliferation/genetics , Fibroblasts/metabolism , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/metabolism , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Neoplasm Metastasis/pathology
5.
Cell ; 152(3): 620-32, 2013 Jan 31.
Article in English | MEDLINE | ID: mdl-23352430

ABSTRACT

DNA double-strand breaks (DSBs) in B lymphocytes arise stochastically during replication or as a result of targeted DNA damage by activation-induced cytidine deaminase (AID). Here we identify recurrent, early replicating, and AID-independent DNA lesions, termed early replication fragile sites (ERFSs), by genome-wide localization of DNA repair proteins in B cells subjected to replication stress. ERFSs colocalize with highly expressed gene clusters and are enriched for repetitive elements and CpG dinucleotides. Although distinct from late-replicating common fragile sites (CFS), the stability of ERFSs and CFSs is similarly dependent on the replication-stress response kinase ATR. ERFSs break spontaneously during replication, but their fragility is increased by hydroxyurea, ATR inhibition, or deregulated c-Myc expression. Moreover, greater than 50% of recurrent amplifications/deletions in human diffuse large B cell lymphoma map to ERFSs. In summary, we have identified a source of spontaneous DNA lesions that drives instability at preferred genomic sites.


Subject(s)
Chromosome Fragile Sites , DNA Replication , Eukaryota/genetics , Genomic Instability , Prokaryotic Cells/physiology , Animals , Biomechanical Phenomena , DNA Repair , Humans
6.
Cell ; 152(4): 691-702, 2013 Feb 14.
Article in English | MEDLINE | ID: mdl-23415220

ABSTRACT

An adaptive variant of the human Ectodysplasin receptor, EDARV370A, is one of the strongest candidates of recent positive selection from genome-wide scans. We have modeled EDAR370A in mice and characterized its phenotype and evolutionary origins in humans. Our computational analysis suggests the allele arose in central China approximately 30,000 years ago. Although EDAR370A has been associated with increased scalp hair thickness and changed tooth morphology in humans, its direct biological significance and potential adaptive role remain unclear. We generated a knockin mouse model and find that, as in humans, hair thickness is increased in EDAR370A mice. We identify new biological targets affected by the mutation, including mammary and eccrine glands. Building on these results, we find that EDAR370A is associated with an increased number of active eccrine glands in the Han Chinese. This interdisciplinary approach yields unique insight into the generation of adaptive variation among modern humans.


Subject(s)
Biological Evolution , Edar Receptor/genetics , Exocrine Glands/physiology , Hair/physiology , Mice , Models, Animal , Adolescent , Adult , Amino Acid Sequence , Animals , Evolution, Molecular , Gene Knock-In Techniques , Genetic Pleiotropy , Haplotypes , Humans , Mice, Inbred C57BL , Middle Aged , Molecular Sequence Data , Polymorphism, Single Nucleotide , Scalp/physiology , Sequence Alignment , Young Adult
7.
Cell ; 153(6): 1266-80, 2013 Jun 06.
Article in English | MEDLINE | ID: mdl-23727112

ABSTRACT

The DNA damage response (DDR) protein 53BP1 protects DNA ends from excessive resection in G1, and thereby favors repair by nonhomologous end-joining (NHEJ) as opposed to homologous recombination (HR). During S phase, BRCA1 antagonizes 53BP1 to promote HR. The pro-NHEJ and antirecombinase functions of 53BP1 are mediated in part by RIF1, the only known factor that requires 53BP1 phosphorylation for its recruitment to double-strand breaks (DSBs). Here, we show that a 53BP1 phosphomutant, 53BP18A, comprising alanine substitutions of the eight most N-terminal S/TQ phosphorylation sites, mimics 53BP1 deficiency by restoring genome stability in BRCA1-deficient cells yet behaves like wild-type 53BP1 with respect to immunoglobulin class switch recombination (CSR). 53BP18A recruits RIF1 but fails to recruit the DDR protein PTIP to DSBs, and disruption of PTIP phenocopies 53BP18A. We conclude that 53BP1 promotes productive CSR and suppresses mutagenic DNA repair through distinct phosphodependent interactions with RIF1 and PTIP.


Subject(s)
Carrier Proteins/metabolism , Chromosomal Proteins, Non-Histone/metabolism , DNA End-Joining Repair , DNA-Binding Proteins/metabolism , Immunoglobulin Class Switching , Nuclear Proteins/metabolism , Telomere-Binding Proteins/metabolism , Animals , B-Lymphocytes/metabolism , BRCA1 Protein/metabolism , Chromosomal Proteins, Non-Histone/genetics , DNA Breaks, Double-Stranded , DNA-Binding Proteins/genetics , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Fibroblasts/metabolism , Genomic Instability , Mice , Mutation , Tumor Suppressor p53-Binding Protein 1
8.
Nat Immunol ; 16(10): 1077-84, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26322481

ABSTRACT

The molecular mechanisms by which signaling via transforming growth factor-ß (TGF-ß) and interleukin 4 (IL-4) control the differentiation of CD4(+) IL-9-producing helper T cells (TH9 cells) remain incompletely understood. We found here that the DNA-binding inhibitor Id3 regulated TH9 differentiation, as deletion of Id3 increased IL-9 production from CD4(+) T cells. Mechanistically, TGF-ß1 and IL-4 downregulated Id3 expression, and this process required the kinase TAK1. A reduction in Id3 expression enhanced binding of the transcription factors E2A and GATA-3 to the Il9 promoter region, which promoted Il9 transcription. Notably, Id3-mediated control of TH9 differentiation regulated anti-tumor immunity in an experimental melanoma-bearing model in vivo and also in human CD4(+) T cells in vitro. Thus, our study reveals a previously unrecognized TAK1-Id3-E2A-GATA-3 pathway that regulates TH9 differentiation.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Inhibitor of Differentiation Proteins/immunology , Interleukin-9/biosynthesis , Neoplasm Proteins/immunology , Animals , Cell Differentiation , Cells, Cultured , Flow Cytometry , Humans , Inhibitor of Differentiation Proteins/genetics , Interleukin-9/immunology , Mice , Neoplasm Proteins/genetics , Polymerase Chain Reaction , Signal Transduction/immunology
9.
Proc Natl Acad Sci U S A ; 121(7): e2315787121, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38315864

ABSTRACT

Charge transport in solids at low temperature reveals a material's mesoscopic properties and structure. Under a magnetic field, Shubnikov-de Haas (SdH) oscillations inform complex quantum transport phenomena that are not limited by the ground state characteristics and have facilitated extensive explorations of quantum and topological interest in two- and three-dimensional materials. Here, in elemental metal Cr with two incommensurately superposed lattices of ions and a spin-density-wave ground state, we reveal that the phases of several low-frequency SdH oscillations in [Formula: see text] and [Formula: see text] are no longer identical but opposite. These relationships contrast with the SdH oscillations from normal cyclotron orbits that maintain identical phases between [Formula: see text] and [Formula: see text] . We trace the origin of the low-frequency SdH oscillations to quantum interference effects arising from the incommensurate orbits of Cr's superposed reciprocal lattices and explain the observed [Formula: see text]-phase shift by the reconnection of anisotropic joint open and closed orbits.

10.
Nature ; 581(7809): 401-405, 2020 05.
Article in English | MEDLINE | ID: mdl-32461649

ABSTRACT

Plasmonics enables the manipulation of light beyond the optical diffraction limit1-4 and may therefore confer advantages in applications such as photonic devices5-7, optical cloaking8,9, biochemical sensing10,11 and super-resolution imaging12,13. However, the essential field-confinement capability of plasmonic devices is always accompanied by a parasitic Ohmic loss, which severely reduces their performance. Therefore, plasmonic materials (those with collective oscillations of electrons) with a lower loss than noble metals have long been sought14-16. Here we present stable sodium-based plasmonic devices with state-of-the-art performance at near-infrared wavelengths. We fabricated high-quality sodium films with electron relaxation times as long as 0.42 picoseconds using a thermo-assisted spin-coating process. A direct-waveguide experiment shows that the propagation length of surface plasmon polaritons supported at the sodium-quartz interface can reach 200 micrometres at near-infrared wavelengths. We further demonstrate a room-temperature sodium-based plasmonic nanolaser with a lasing threshold of 140 kilowatts per square centimetre, lower than values previously reported for plasmonic nanolasers at near-infrared wavelengths. These sodium-based plasmonic devices show stable performance under ambient conditions over a period of several months after packaging with epoxy. These results indicate that the performance of plasmonic devices can be greatly improved beyond that of devices using noble metals, with implications for applications in plasmonics, nanophotonics and metamaterials.

11.
Nature ; 586(7830): 572-577, 2020 10.
Article in English | MEDLINE | ID: mdl-32726802

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a respiratory disease called coronavirus disease 2019 (COVID-19), the spread of which has led to a pandemic. An effective preventive vaccine against this virus is urgently needed. As an essential step during infection, SARS-CoV-2 uses the receptor-binding domain (RBD) of the spike protein to engage with the receptor angiotensin-converting enzyme 2 (ACE2) on host cells1,2. Here we show that a recombinant vaccine that comprises residues 319-545 of the RBD of the spike protein induces a potent functional antibody response in immunized mice, rabbits and non-human primates (Macaca mulatta) as early as 7 or 14 days after the injection of a single vaccine dose. The sera from the immunized animals blocked the binding of the RBD to ACE2, which is expressed on the cell surface, and neutralized infection with a SARS-CoV-2 pseudovirus and live SARS-CoV-2 in vitro. Notably, vaccination also provided protection in non-human primates to an in vivo challenge with SARS-CoV-2. We found increased levels of RBD-specific antibodies in the sera of patients with COVID-19. We show that several immune pathways and CD4 T lymphocytes are involved in the induction of the vaccine antibody response. Our findings highlight the importance of the RBD domain in the design of SARS-CoV-2 vaccines and provide a rationale for the development of a protective vaccine through the induction of antibodies against the RBD domain.


Subject(s)
Antibodies, Viral/immunology , Betacoronavirus/immunology , Coronavirus Infections/immunology , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/immunology , Pneumonia, Viral/prevention & control , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Viral Vaccines/immunology , Animals , Antibodies, Neutralizing/immunology , COVID-19 , COVID-19 Vaccines , Humans , Macaca mulatta/immunology , Macaca mulatta/virology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Models, Animal , Models, Molecular , Protein Domains , SARS-CoV-2 , Serum/immunology , Spleen/cytology , Spleen/immunology , T-Lymphocytes/immunology , Vaccination
12.
J Biol Chem ; 300(1): 105510, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38042492

ABSTRACT

Tendinopathy is a disorder of musculoskeletal system that primarily affects athletes and the elderly. Current treatment options are generally comprised of various exercise and loading programs, therapeutic modalities, and surgical interventions and are limited to pain management. This study is to understand the role of TRIM54 (tripartite motif containing 54) in tendonitis through in vitro modeling with tendon-derived stem cells (TDSCs) and in vivo using rat tendon injury model. Initially, we observed that TRIM54 overexpression in TDSCs model increased stemness and decreased apoptosis. Additionally, it rescued cells from tumor necrosis factor α-induced inflammation, migration, and tenogenic differentiation. Further, through immunoprecipitation studies, we identified that TRIM54 regulates inflammation in TDSCs by binding to and ubiquitinating YOD1. Further, overexpression of TRIM54 improved the histopathological score of tendon injury as well as the failure load, stiffness, and young modulus in vivo. These results indicated that TRIM54 played a critical role in reducing the effects of tendon injury. Consequently, these results shed light on potential therapeutic alternatives for treating tendinopathy.


Subject(s)
Endopeptidases , Muscle Proteins , Tendinopathy , Thiolester Hydrolases , Aged , Animals , Humans , Rats , Apoptosis , Cell Differentiation/physiology , Endopeptidases/metabolism , Stem Cells , Tendinopathy/metabolism , Tendon Injuries/therapy , Tendon Injuries/metabolism , Tendons/metabolism , Thiolester Hydrolases/metabolism , Muscle Proteins/metabolism
13.
PLoS Pathog ; 19(10): e1011694, 2023 10.
Article in English | MEDLINE | ID: mdl-37831643

ABSTRACT

Alongshan virus (ALSV), a newly discovered member of unclassified Flaviviridae family, is able to infect humans. ALSV has a multi-segmented genome organization and is evolutionarily distant from canonical mono-segmented flaviviruses. The virus-encoded methyltransferase (MTase) plays an important role in viral replication. Here we show that ALSV MTase readily binds S-adenosyl-L-methionine (SAM) and S-adenosyl-L-homocysteine (SAH) but exhibits significantly lower affinities than canonical flaviviral MTases. Structures of ALSV MTase in the free and SAM/SAH-bound forms reveal that the viral enzyme possesses a unique loop-element lining side-wall of the SAM/SAH-binding pocket. While the equivalent loop in flaviviral MTases half-covers SAM/SAH, contributing multiple hydrogen-bond interactions; the pocket-lining loop of ALSV MTase is of short-length and high-flexibility, devoid of any physical contacts with SAM/SAH. Subsequent mutagenesis data further corroborate such structural difference affecting SAM/SAH-binding. Finally, we also report the structure of ALSV MTase bound with sinefungin, an SAM-analogue MTase inhibitor. These data have delineated the basis for the low-affinity interaction between ALSV MTase and SAM/SAH and should inform on antiviral drug design.


Subject(s)
Flavivirus , Methyltransferases , Humans , Methyltransferases/genetics , Flavivirus/genetics , Flavivirus/metabolism , S-Adenosylmethionine/metabolism , Mutagenesis
14.
Hepatology ; 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38537134

ABSTRACT

BACKGROUND AND AIMS: HBV infection is a major etiology of acute-on-chronic liver failure (ACLF). At present, the pattern and regulation of hepatocyte death during HBV-ACLF progression are still undefined. Evaluating the mode of cell death and its inducers will provide new insights for developing therapeutic strategies targeting cell death. In this study, we aimed to elucidate whether and how immune landscapes trigger hepatocyte death and lead to the progression of HBV-related ACLF. APPROACH AND RESULTS: We identified that pyroptosis represented the main cell death pattern in the liver of patients with HBV-related ACLF. Deficiency of MHC-I in HBV-reactivated hepatocytes activated cytotoxic NK cells, which in turn operated in a perforin/granzyme-dependent manner to trigger GSDMD/caspase-8-dependent pyroptosis of hepatocytes. Neutrophils selectively accumulated in the pyroptotic liver, and HMGB1 derived from the pyroptotic liver constituted an important factor triggering the generation of pathogenic extracellular traps in neutrophils (NETs). Clinically, elevated plasma levels of myeloperoxidase-DNA complexes were a promising prognostic biomarker for HBV-related ACLF. More importantly, targeting GSDMD pyroptosis-HMGB1 release in the liver abrogates NETs that intercept the development of HBV-related ACLF. CONCLUSIONS: Studying the mechanisms that selectively modulate GSDMD-dependent pyroptosis, as well as its immune landscapes, will provide a novel strategy for restoring the liver function of patients with HBV-related ACLF.

15.
Plant Cell ; 34(1): 579-596, 2022 01 20.
Article in English | MEDLINE | ID: mdl-34735009

ABSTRACT

The self-incompatibility (SI) system with the broadest taxonomic distribution in angiosperms is based on multiple S-locus F-box genes (SLFs) tightly linked to an S-RNase termed type-1. Multiple SLFs collaborate to detoxify nonself S-RNases while being unable to detoxify self S-RNases. However, it is unclear how such a system evolved, because in an ancestral system with a single SLF, many nonself S-RNases would not be detoxified, giving low cross-fertilization rates. In addition, how the system has been maintained in the face of whole-genome duplications (WGDs) or lost in other lineages remains unclear. Here we show that SLFs from a broad range of species can detoxify S-RNases from Petunia with a high detoxification probability, suggestive of an ancestral feature enabling cross-fertilization and subsequently modified as additional SLFs evolved. We further show, based on its genomic signatures, that type-1 was likely maintained in many lineages, despite WGD, through deletion of duplicate S-loci. In other lineages, SI was lost either through S-locus deletions or by retaining duplications. Two deletion lineages regained SI through type-2 (Brassicaceae) or type-4 (Primulaceae), and one duplication lineage through type-3 (Papaveraceae) mechanisms. Thus, our results reveal a highly dynamic process behind the origin, maintenance, loss, and regain of SI.


Subject(s)
Biological Evolution , Germ Cells, Plant/physiology , Magnoliopsida/physiology , Self-Incompatibility in Flowering Plants , Self-Incompatibility in Flowering Plants/genetics
16.
PLoS Comput Biol ; 20(1): e1011786, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38252662

ABSTRACT

Adapter trimming is an essential step for analyzing small RNA sequencing data, where reads are generally longer than target RNAs ranging from 18 to 30 bp. Most adapter trimming tools require adapter information as input. However, adapter information is hard to access, specified incorrectly, or not provided with publicly available datasets, hampering their reproducibility and reusability. Manual identification of adapter patterns from raw reads is labor-intensive and error-prone. Moreover, the use of randomized adapters to reduce ligation biases during library preparation makes adapter detection even more challenging. Here, we present FindAdapt, a Python package for fast and accurate detection of adapter patterns without relying on prior information. We demonstrated that FindAdapt was far superior to existing approaches. It identified adapters successfully in 180 simulation datasets with diverse read structures and 3,184 real datasets covering a variety of commercial and customized small RNA library preparation kits. FindAdapt is stand-alone software that can be easily integrated into small RNA sequencing analysis pipelines.


Subject(s)
High-Throughput Nucleotide Sequencing , Software , Reproducibility of Results , RNA , Sequence Analysis, RNA
17.
Cell ; 141(2): 243-54, 2010 Apr 16.
Article in English | MEDLINE | ID: mdl-20362325

ABSTRACT

Defective DNA repair by homologous recombination (HR) is thought to be a major contributor to tumorigenesis in individuals carrying Brca1 mutations. Here, we show that DNA breaks in Brca1-deficient cells are aberrantly joined into complex chromosome rearrangements by a process dependent on the nonhomologous end-joining (NHEJ) factors 53BP1 and DNA ligase 4. Loss of 53BP1 alleviates hypersensitivity of Brca1 mutant cells to PARP inhibition and restores error-free repair by HR. Mechanistically, 53BP1 deletion promotes ATM-dependent processing of broken DNA ends to produce recombinogenic single-stranded DNA competent for HR. In contrast, Lig4 deficiency does not rescue the HR defect in Brca1 mutant cells but prevents the joining of chromatid breaks into chromosome rearrangements. Our results illustrate that HR and NHEJ compete to process DNA breaks that arise during DNA replication and that shifting the balance between these pathways can be exploited to selectively protect or kill cells harboring Brca1 mutations.


Subject(s)
BRCA1 Protein/genetics , DNA Repair , Intracellular Signaling Peptides and Proteins/metabolism , Animals , B-Lymphocytes/metabolism , Chromosomal Proteins, Non-Histone , DNA Breaks , DNA-Binding Proteins , Female , Genomic Instability , Humans , Mice , Tumor Suppressor p53-Binding Protein 1
18.
Nature ; 565(7741): 627-630, 2019 01.
Article in English | MEDLINE | ID: mdl-30651643

ABSTRACT

The spin Hall effect (SHE)1-5 achieves coupling between charge currents and collective spin dynamics in magnetically ordered systems and is a key element of modern spintronics6-9. However, previous research has focused mainly on non-magnetic materials, so the magnetic contribution to the SHE is not well understood. Here we show that antiferromagnets have richer spin Hall properties than do non-magnetic materials. We find that in the non-collinear antiferromagnet10 Mn3Sn, the SHE has an anomalous sign change when its triangularly ordered moments switch orientation. We observe contributions to the SHE (which we call the magnetic SHE) and the inverse SHE (the magnetic inverse SHE) that are absent in non-magnetic materials and that can be dominant in some magnetic materials, including antiferromagnets. We attribute the dominance of this magnetic mechanism in Mn3Sn to the momentum-dependent spin splitting that is produced by non-collinear magnetic order. This discovery expands the horizons of antiferromagnet spintronics and spin-charge coupling mechanisms.

19.
Nature ; 566(7742): E4, 2019 02.
Article in English | MEDLINE | ID: mdl-30670875

ABSTRACT

In this Letter, the formatting of some of the crystallographic axes was incorrect. This has been corrected online.

20.
Nature ; 567(7746): 105-108, 2019 03.
Article in English | MEDLINE | ID: mdl-30787433

ABSTRACT

Genomic instability can trigger cellular responses that include checkpoint activation, senescence and inflammation1,2. Although genomic instability has been extensively studied in cell culture and cancer paradigms, little is known about its effect during embryonic development, a period of rapid cellular proliferation. Here we report that mutations in the heterohexameric minichromosome maintenance complex-the DNA replicative helicase comprising MCM2 to MCM73,4-that cause genomic instability render female mouse embryos markedly more susceptible than males to embryonic lethality. This bias was not attributable to X chromosome-inactivation defects, differential replication licensing or X versus Y chromosome size, but rather to 'maleness'-XX embryos could be rescued by transgene-mediated sex reversal or testosterone administration. The ability of exogenous or endogenous testosterone to protect embryos was related to its anti-inflammatory properties5. Ibuprofen, a non-steroidal anti-inflammatory drug, rescued female embryos that contained mutations in not only the Mcm genes but also the Fancm gene; similar to MCM mutants, Fancm mutant embryos have increased levels of genomic instability (measured as the number of cells with micronuclei) from compromised replication fork repair6. In addition, deficiency in the anti-inflammatory IL10 receptor was synthetically lethal with the Mcm4Chaos3 helicase mutant. Our experiments indicate that, during development, DNA damage associated with DNA replication induces inflammation that is preferentially lethal to female embryos, because male embryos are protected by high levels of intrinsic testosterone.


Subject(s)
Embryo Loss/genetics , Genomic Instability/genetics , Inflammation/genetics , Minichromosome Maintenance Proteins/genetics , Mutation , Sex Characteristics , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cell Proliferation , DNA Damage , DNA Helicases/genetics , DNA Replication , Embryo Loss/pathology , Embryo Loss/prevention & control , Embryonic Development/drug effects , Embryonic Development/genetics , Female , Ibuprofen/pharmacology , Inflammation/pathology , Inflammation/prevention & control , Male , Mice , Minichromosome Maintenance Complex Component 4/genetics , Minichromosome Maintenance Proteins/deficiency , Placenta/metabolism , Placenta/pathology , Pregnancy , Receptors, Interleukin-10/deficiency , Receptors, Interleukin-10/genetics , Synthetic Lethal Mutations , Testosterone/pharmacology
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