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Invertebrates mainly rely on sequence-specific RNA interference (RNAi) to resist viral infections. Increasing studies show that double-stranded RNA (dsRNA) can induce sequence-independent protection and that Dicer-2, the key RNAi player that cleaves long dsRNA into small interfering RNA (siRNA), is necessary for this protection. However, how this protection occurs remains unknown. Herein, we report that it is caused by adenosine triphosphate (ATP)-hydrolysis accompanying the dsRNA-cleavage. Dicer-2 helicase domain is ATP-dependent; therefore, the cleavage consumes ATP. ATP depletion activates adenosine monophosphate-activated protein kinase (Ampk) and induces nuclear localization of Fork head box O (FoxO), a key transcriptional factor for dsRNA-induced genes. siRNAs that do not require processing cannot activate the transcriptional response. This study reveals a unique nonspecific antiviral mechanism other than the specific RNAi in shrimp. This mechanism is functionally similar to, but mechanistically different from, the dsRNA-activated antiviral response in vertebrates and suggests an interesting evolution of innate antiviral immunity.
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Proteínas Quinasas Activadas por AMP , Adenosina Trifosfato , ARN Bicatenario , Ribonucleasa III , Animales , ARN Bicatenario/metabolismo , Ribonucleasa III/metabolismo , Ribonucleasa III/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Trifosfato/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Inmunidad Innata , Transcripción GenéticaRESUMEN
The arthropod exoskeleton provides protection and support and is vital for survival and adaption. The integrity and mechanical properties of the exoskeleton are often impaired after pathogenic infection; however, the detailed mechanism by which infection affects the exoskeleton remains largely unknown. Here, we report that the damage to the shrimp exoskeleton is caused by modulation of host lipid profiles after infection with white spot syndrome virus (WSSV). WSSV infection disrupts the mechanical performance of the exoskeleton by inducing the expression of a chitinase (Chi2) in the sub-cuticle epidermis and decreasing the cuticle chitin content. The induction of Chi2 expression is mediated by a nuclear receptor that can be activated by certain enriched long-chain saturated fatty acids after infection. The damage to the exoskeleton, an aftereffect of the induction of host lipogenesis by WSSV, significantly impairs the motor ability of shrimp. Blocking the WSSV-caused lipogenesis restored the mechanical performance of the cuticle and improved the motor ability of infected shrimp. Therefore, this study reveals a mechanism by which WSSV infection modulates shrimp internal metabolism resulting in phenotypic impairment, and provides new insights into the interactions between the arthropod host and virus.
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Exoesqueleto , Metabolismo de los Lípidos , Penaeidae , Virus del Síndrome de la Mancha Blanca 1 , Animales , Penaeidae/virología , Penaeidae/metabolismo , Exoesqueleto/metabolismo , Exoesqueleto/virología , Virus del Síndrome de la Mancha Blanca 1/fisiología , Metabolismo de los Lípidos/fisiología , Interacciones Huésped-Patógeno , Lipogénesis/fisiologíaRESUMEN
Disease emergence is the consequence of host-pathogen-environment interactions. Ammonia is a key stress factor in aquatic environments that usually increases the risk of pathogenic diseases in aquatic animals. However, the molecular regulatory mechanisms underlying the enhancement of viral infection following ammonia stress remain largely unknown. Here, we found that ammonia stress enhances white spot syndrome virus infection in kuruma shrimp (Marsupenaeus japonicus) by targeting the antiviral interferon-like system through heat shock factor 1 (Hsf1). Hsf1 is an ammonia-induced transcription factor. It regulates the expression of Cactus and Socs2, which encode negative regulators of NF-κB signaling and Jak/Stat signaling, respectively. By inhibiting these two pathways, ammonia-induced Hsf1 suppressed the production and function of MjVago-L, an arthropod interferon analog. Therefore, this study revealed that Hsf1 is a central regulator of suppressed antiviral immunity after ammonia stress and provides new insights into the molecular regulation of immunity in stressful environments. IMPORTANCE: Ammonia is the end product of protein catabolism and is derived from feces and unconsumed foods. It threatens the health and growth of aquatic animals. In this study, we demonstrated that ammonia stress suppresses shrimp antiviral immunity by targeting the shrimp interferon-like system and that heat shock factor 1 (Hsf1) is a central regulator of this process. When shrimp are stressed by ammonia, they activate Hsf1 for stress relief and well-being. Hsf1 upregulates the expression of negative regulators that inhibit the production and function of interferon analogs in shrimp, thereby enhancing white spot syndrome viral infection. Therefore, this study, from a molecular perspective, explains the problem in the aquaculture industry that animals living in stressed environments are more susceptible to pathogens than those living in unstressed conditions. Moreover, this study provides new insights into the side effects of heat shock responses and highlights the complexity of achieving cellular homeostasis under stressful conditions.
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Penaeidae , Virosis , Virus del Síndrome de la Mancha Blanca 1 , Animales , Interferones/metabolismo , Virus del Síndrome de la Mancha Blanca 1/fisiología , Amoníaco/metabolismo , Respuesta al Choque TérmicoRESUMEN
OBJECTIVE: To compare the efficacy and clinical value of high-throughput sequencing (HTS) and Sanger sequencing in detecting ABL kinase domain mutations in patients with chronic myeloid leukemia (CML). METHODS: A total of 198 samples of 147 CML patients from July 2017 to March 2021 in Henan Cancer Hospital were collected and underwent high-throughput sequencing and Sanger sequencing to detect the mutations in ABL kinase domain, and the relevant clinical data were collected for comparative analysis. RESULTS: The proportion of total mutations and ≥2 mutations detected by high-throughput sequencing were significantly higher than those detected by Sanger sequencing (P =0.01; P =0.046). ≥2 mutations were detected in 22 cases, of which 5 cases (22.7%) had compound mutations. High-throughput sequencing can detect low level mutations that cannot be detected by Sanger sequencing. In 198 samples, 25 (12.6%) were low level mutations, 33 (16.7%) were high level mutations and 10 (5.1%) were mixed high and low level mutations. In the analysis of related clinical factors, the total mutation rate and the low level mutation rate in the optimal period, failure period and warning period were gradually increased (total mutation rate, P =0.016; low level mutation rate, P =0.005). The mutation rate of the samples with additional chromosomal abnormalities was also significantly increased (P =0.009). The mutation rate of patients who received first- and second-line treatment was significantly lower than that of patients who received third- or higher-line treatment (P =0.006). Analysis based on variant allele frequency (VAF) of the mutation site was helpful to visually evaluate the clonal evolution status of TKI-resistance CML cells. CONCLUSION: High-throughput sequencing is more sensitive and accurate than Sanger sequencing in mutation detection, which is helpful to accurately and visually evaluate TKI treatment response and optimize treatment strategy for CML.
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Proteínas de Fusión bcr-abl , Leucemia Mielógena Crónica BCR-ABL Positiva , Humanos , Proteínas de Fusión bcr-abl/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Resistencia a Antineoplásicos/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Mutación , Secuenciación de Nucleótidos de Alto RendimientoRESUMEN
Dissolved organic carbon (DOC) plays a crucial role in the assessment of greenhouse gas emission and carbon balance in peatlands. However, limited research has been conducted on the seasonal variations and properties of soil water DOC content at different depths in the permafrost peatlands of the Great Hing'an Mountains. In this study, we analyzed the seasonal patterns of soil water DOC contents (surface, 10 cm, 20 cm, 30 cm, 40 cm, and permafrost layer) the permafrost peatlands of the Great Hing'an Mountains (Tuqiang Forestry Bureau), and investigated the influencing factors, such as electrical conductivity, dissolved oxygen, HCO3- concentration, pH value, oxidation-reduction potential, and CO2 content. The stability of DOC was assessed by using UV-Vis spectrum. There were significant seasonal dynamics of DOC content in soil water, with higher contents in autumn and lower content in summer, ranging from 55.7 to 188.1 mg·L-1. There were significant differences in DOC content among different soil depths, with the highest levels detected in the permafrost layer. The DOC content showed a significantly positive correlation with pH value and electrical conductivity, while showed a significantly negative correlation with redox potential, HCO3- concentration, and dissolved oxygen content. Additionally, there was a significantly positive correlation between DOC and CO2 contents. The dissolved CO2 content in soil water increased with soil depth, with the highest content observed in the permafrost layer. Results of spectral analysis showed higher aromaticity in autumn compared to summer, indicating greater stability of DOC during the autumn season. Our results clarified the seasonal variations of soil water DOC in permafrost peatlands of the Great Hing'an Mountains and could provide important data to understand the carbon cycling in the region.
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Hielos Perennes , Suelo , Suelo/química , Estaciones del Año , Hielos Perennes/química , Materia Orgánica Disuelta , Agua/análisis , Dióxido de Carbono/análisis , Carbono/análisis , OxígenoRESUMEN
OBJECTIVE: Efferocytosis dysfunction contributes to the progression and rupture of atherosclerotic plaques. Efferocytosis is crucially modulated by intracytoplasmic Ca2+, and mitochondrial calcium uniporter (MCU) complex proteins serve as key channels for regulating Ca2+ concentration. Therefore, it was speculated that MCU may affect the development of atherosclerosis (AS) by regulating efferocytosis. In the present study, we aimed to investigate whether MCU could affect foam cell formation by regulating efferocytosis. METHODS: We stimulated primary macrophages (Møs) using oxidized low-density lipoprotein (ox-LDL) to mimic the atherosclerotic microenvironment and treated them with Ru360, an MCU-specific inhibitor, and UNC1062, an inhibitor of efferocytosis. Additionally, we conducted double staining to determine the Mø efferocytosis rate. We measured the expression of MCU complexes and efferocytosis-associated proteins using western blotting (WB) and real-time quantitative polymerase chain reaction (RT-qPCR), respectively. In addition, we separately detected the Ca2+ level in the cytoplasm and mitochondria (MT) using Fluo-4 AM and Rhod-2 methods. We separately determined the reactive oxygen species (ROS) level in cytoplasm and MT using dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescent probing method and Mito-SOXTM superoxide indicator staining. Additionally, we conducted the enzyme-linked immunosorbent assay (ELISA) to detect the production of interleukin-6 (IL-6), interleukin-18 (IL-18), interleukin-1ß (IL-1ß), and tumor necrosis factor-alpha (TNF-α). Oil Red O staining was performed to measure cytoplasmic lipid levels. RESULTS: Ru360 attenuated ox-LDL-induced efferocytosis dysfunction, and attenuated the upregulation of MCU and MCUR1 induced by ox-LDL, and meanwhile attenuated the downregulation of MCUb induced by ox-LDL. Ru360 attenuated the decrease of intracytoplasmic Ca2+ concentration induced by ox- LDL, Ru360 also attenuated the ROS production induced by ox- LDL, attenuated the release of IL-6, IL-18, IL-1ß, and TNF-α induced by ox- LDL, and attenuated the increase of intracytoplasmic lipid content induced by ox-LDL. UNC1062 attenuated the effects of Ru360 in reducing inflammatory cytokines and intracytoplasmic lipid content. CONCLUSIONS: In this study, we found that MCU inhibition modulated intracytoplasmic Ca2+ concentration, improved impaired Mø efferocytosis, and reduced ROS generation. Macrophage efferocytosis removed apoptotic cells and prevented the release of inflammatory factor and foam cell formation, and this can be a potential new therapeutic target for alleviating atherosclerosis.
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Aterosclerosis , Interleucina-18 , Animales , Ratones , Especies Reactivas de Oxígeno/metabolismo , Interleucina-18/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Modelos Animales de Enfermedad , Macrófagos/metabolismo , Lipoproteínas LDL/farmacología , Lipoproteínas LDL/metabolismo , Aterosclerosis/patologíaRESUMEN
Crayfish, as an invertebrate, relies only on the innate immune system to resist external pathogens. In this study, a molecule containing a single Reeler domain was identified from red swamp crayfish Procambarus clarkii (named as PcReeler). Tissue distribution analysis showed that PcReeler was highly expressed in gills and its expression was induced by bacterial stimulation. Inhibiting the expression of PcReeler by RNA interference led to a significant increase in the bacterial abundance in the gills of crayfish, and a significant increase in the crayfish mortality. Silencing of PcReeler influenced the stability of the microbiota in the gills revealed by 16S rDNA high-throughput sequencing. Recombinant PcReeler showed the ability to bind microbial polysaccharide and bacteria and to inhibit the formation of bacterial biofilms. These results provided direct evidence for the involvement of PcReeler in the antibacterial immune mechanism of P. clarkii.
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BACKGROUND: More and more novel anticancer drugs have been approved for patients with hematological malignancies in recent years, but HBV reactivation (HBV-R) data in this population is very scarce. This study aimed to evaluated HBV-R risk in patients with hematological malignancies receiving novel anticancer drugs. METHODS: HBV markers and serum HBV DNA levels of patients with hematological malignancies receiving novel anticancer drugs in a tertiary cancer hospital were retrospectively collected. HBV-R risk in the whole cohort and subgroups was described. The relevant literature was reviewed to make a pooled analysis. RESULTS: Of 845 patients receiving novel anticancer drugs, 258 (30.5%) were considered at risk for HBV-R. The median duration of exposure to novel drugs was 5.6 (0.1-67.6) months. The incidence of HBV-R was 2.1% in patients with past HBV infection without prophylactic antiviral treatment (PAT) and 1.2% in all patients at risk of HBV-R. In a pooled analysis of 11 studies with 464 patients, the incidence of HBV-R was 2.4% (95% CI: 1.3-4.2) in all at-risk patients receiving novel anticancer drugs and 0.6% (95% CI: 0.03-3.5) in patients with anticancer drugs plus PAT. The incidence of death due to HBV-R was 0.4% (95% CI: 0.1-1.6) in all at-risk patients and 18.2% (95% CI: 3.2-47.7) in patients with HBV-R. CONCLUSION: Most episodes of HBV-R are preventable, and most cases with HBV-R are manageable. We recommend that novel anticancer drugs should not be intentionally avoided when treating cancer patients with HBV infection.
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Antineoplásicos , Neoplasias Hematológicas , Hepatitis B , Neoplasias , Humanos , Virus de la Hepatitis B/genética , Incidencia , Estudios Retrospectivos , Antineoplásicos/efectos adversos , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/tratamiento farmacológico , Antivirales/uso terapéutico , Antivirales/farmacología , Activación Viral , Hepatitis B/tratamiento farmacológico , Hepatitis B/epidemiología , Antígenos de Superficie de la Hepatitis BRESUMEN
In the arthropod gut, commensal microbiota maintain the immune deficiency (Imd)/Relish pathway for expression of antimicrobial peptides, whereas pathogenic bacteria induce dual oxidase 2 (Duox2) for production of extracellular microbicidal reactive oxygen species (ROS). The Imd/Relish pathway and the Duox2/ROS system are regarded as independent systems. Here, we report that these two systems are bridged by the tumor necrosis factor (TNF) ortholog PcEiger in the red swamp crayfish Procambarus clarkii. PcEiger expression is induced by commensal bacteria or the Imd/Relish pathway. PcEiger knockdown alters bacterial abundance and community composition due to variations in the oxidative status of the intestine. PcEiger induces Duox2 expression and ROS production by regulating the activity of the transcription factor Atf2. Moreover, PcEiger mediates regulation of the Duox2/ROS system by commensal bacteria and the Imd/Relish pathway. Our findings suggest that the Imd/Relish pathway regulates the Duox2/ROS system via PcEiger in P. clarkii, and they provide insights into the crosstalk between these two important mechanisms for arthropod intestinal immunity.
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Astacoidea , Factores de Transcripción , Animales , Astacoidea/metabolismo , Astacoidea/microbiología , Especies Reactivas de Oxígeno , Oxidasas Duales/genética , Factores de Transcripción/metabolismo , Intestinos , Inmunidad InnataRESUMEN
Mindin is a secreted extracellular matrix protein that is involved in regulating cellular events through interacting with integrin. Studies have demonstrated its role in host immunity, including phagocytosis, cell migration, and cytokine production. However, the function of Mindin in the host-virus interaction is largely unknown. In the present study, we report that Mindin facilitates virus infection by activating lipid utilization in an arthropod, kuruma shrimp (Marsupenaeus japonicus). Shrimp Mindin facilitates white spot syndrome virus infection by facilitating viral entry and replication. By activating autophagy, Mindin induces lipid droplet consumption, the hydrolysis of triglycerides into free fatty acids, and ATP production, ultimately providing energy for virus infection. Moreover, integrin is essential for Mindin-mediated autophagy and lipid utilization. Therefore, by revealing the mechanism by which Mindin facilitates virus infection through regulating lipid metabolism, the present study reveals the significance of Mindin in the host-virus interaction. IMPORTANCE White spot syndrome virus (WSSV) is an enveloped double-stranded DNA virus that has had a serious influence on worldwide shrimp farming in the last 30 years. We have demonstrated that WSSV hijacks host autophagy and lipid metabolism for reproduction in kuruma shrimp (Marsupenaeus japonicus). These findings revealed the mechanism by which WSSV exploits host machinery for its infection and provided serial targets for WSSV prevention and control in shrimp farming.
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Virus del Síndrome de la Mancha Blanca 1 , Animales , Virus del Síndrome de la Mancha Blanca 1/genética , Autofagia , Crustáceos , Proteínas de la Matriz Extracelular , LípidosRESUMEN
BACKGROUND: Since the 1990s, drylands have been extensively converted to rice paddy fields on the former wetlands in the Sanjiang Plain of northeast China. However, the influence of this successiveland-use change from native wetlands to drylands to rice paddy fields on soil organic carbon (C) dynamics remains unexplored. Here, we compared the difference in soil organic C stock among native wetlands, drylands, and paddy fields, and then used a two-step acid hydrolysis approach to examine the effect of this land-use change on labile C I (LPI-C), labile C II (LPII-C), and recalcitrant C (RP-C) fractions at depths of 0-15 cm, 15-30 cm, and 30-50 cm. RESULTS: Soil organic C stock at a depth of 0-50 cm was reduced by 79% after the conversion of wetlands to drylands but increased by 24% when drylands were converted to paddy fields. Compared with wetlands, paddy fields had 74% lower soil organic C stock at a depth of 0-50 cm. The conversion of wetlands to drylands reduced the concentrations of LPI-C, LPII-C, and RP-C fractions at each soil depth. However, land-use change from drylands to paddy fields only increased the concentrations of LPI-C and LPII-C fractions at the 0-15 cm and 30-50 cm depths. CONCLUSION: The conversion of drylands to paddy lands on former wetlands enhances the soil organic C stock by promoting labile C fraction accumulation, and labile C fractions are more sensitive to this successive land-use change than recalcitrant C fractions in the Sanjiang Plain of northeast China. © 2022 Society of Chemical Industry.
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Carbono , Oryza , Humedales , Suelo , Translocación Genética , Yoduros , Anticuerpos , ChinaRESUMEN
As an important part of innate immune system, complement system is widely involved in defense response and immune regulation, and plays an important biological role. The complement system has been deeply studied. More than 30 complement-related molecules and three major complement-activation pathways have been identified in vertebrates. Crustacean animals do not have complement system. There are only some complement-related proteins in crustaceans which are important for host defense. In this review, we summarize the current knowledge about complement-related proteins in crustaceans, and their functions in crustacean immunity. We also make a comparation of the crustacean pro-phenoloxidase activating system and the mammalian complement system. This review provides a better understanding of the evolution and function of complement-related proteins in crustaceans.
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Crustáceos , AnimalesRESUMEN
Small antibacterial effectors, including lysozymes, lectins, and antimicrobial peptides, are key regulators of intestinal immunity. However, whether there is coordination among them during regulation is an interesting, but largely unknown, issue. In the present study, we revealed that small effectors synergistically regulate peptidoglycan-derived intestinal immunity in the kuruma shrimp, Marsupenaeus japonicus. A C-type lysozyme (LysC) was screened as a responsive factor for the intestine-bacteria interaction. LysC functions to restrict intestinal bacteria, mainly by cleaving Photobacterium damselae peptidoglycan to generate muropeptides which are powerful stimulators that induce anti-lipopolysaccharides factor B1 (AlfB1), an effective bactericidal peptide. The muropeptides also induce a C-type lectin (Ctl24), which recognizes peptidoglycan and coats bacteria. By counteracting LysC-mediated muropeptide release and AlfB1's bactericidal activity, Ctl24 prevents the continuous elimination of intestinal bacteria. Therefore, this study demonstrates a mechanism by which small immune effectors coordinate to achieve intestinal homeostasis, and provides new insights into peptidoglycan-derived intestinal immunity in invertebrates.
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Penaeidae , Peptidoglicano , Animales , Pared Celular , Intestinos , Lectinas Tipo CRESUMEN
Background: Heat shock protein family D (Hsp60) member 1 (HSPD1) has been reported as a potential survival-related biomarker in some cancers. However, the correlation between HSPD1 expression with prognosis and clinical features of esophageal cancer (EC) is poorly understood. Our research aimed to explore the clinical and prognostic significance of HSPD1 expression in EC patients. Methods: In our study, HSPD1 expression was detected by immunochemistry in 87 EC tissue specimens and 20 normal cancerous peripheral tissue specimens. Meanwhile, we also analyzed the expression of HSPD1 in EC by The Cancer Genome Atlas (TCGA) database. Then Chi-squared and Fisher's exact tests and Wilcoxon signed-rank test and logistic regression models were separately used to test the correlation between clinical characteristics and HSPD1 expression in our and TCGA cohort. Moreover, we evaluated the value of HSPD1 in prognosis by Kaplan-Meier curves and Cox analysis. Finally, gene set enrichment analysis (GSEA) was performed using the data accessed from TCGA. Results: The results showed that HSPD1 was overexpressed in EC, and the expression was related to histological type, histological grade, N classification, and clinical stage. Moreover, Kaplan-Meier curves and Cox analysis indicated that high expression of HSPD1 correlated with poor prognosis, and HSPD1 was an independent risk factor for EC. GSEA identified pathways involved in cysteine and methionine metabolism, spliceosome, selenoamino acid metabolism, mismatch repair, RNA degration, DNA replication, and cell cycle as differentially enriched in ECs with high HSPD1 expression. Conclusions: Our results suggest that HSPD1 is expressed at high levels in EC, and has potential to be used as a novel biomarker for the prognosis of patients with EC.
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Boreal peatlands have been experiencing increased abundances of symbiotic dinitrogen-fixing woody plants (mainly alder species). However, how alder encroachment alters soil organic carbon (C) pool and stability is unclear. To examine the effects of alder encroachment on soil organic C, we measured soil organic C pool, phenol oxidase (POX) activity, organic C mineralization rate, and organic C chemical structure (alkyl C, O-alkyl C, aromatic C, and carbonyl C) using solid-state 13C nuclear magnetic resonance spectroscopy in the 0-10 cm, 10-20 cm, and 20-40 cm depths in the Alnus sibirica islands and adjacent open peatlands in the north of Da'xingan Mountain, Northeast China. A. sibirica islands had 28 %, 25 %, and 30 % greater POX activity and 36 %, 31 %, and 100 % higher organic C mineralization than open peatlands in the 0-10 cm, 10-20 cm, and 20-40 cm soil depths, respectively. Despite no significant changes in the 0-10 cm and 10-20 cm depths, alder encroachment reduced soil organic C pool in the 20-40 cm depth. Soil organic C pool in the 0-40 cm depth was lower in A. sibirica islands (298 Mg ha-1) than in the open peatlands (315 Mg ha-1). Moreover, alder encroachment increased alkyl (7 %) and carbonyl (57 %) C fractions but reduced O-alkyl C fraction (16 %) in the 20-40 cm depth, resulting in increased aliphaticity and recalcitrance indices. These findings suggest that alder encroachment will reduce soil organic C accumulation by accelerating microbial decomposition, and highlight that increased biochemical stabilization would attenuate soil organic C loss after alder expansion in boreal peatlands. Our results will help assess and project future C budgets in boreal peatlands.
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Alnus , Carbono , Carbono/química , China , Monofenol Monooxigenasa , Suelo/químicaRESUMEN
Hedgehog (Hh) is a morphogen that binds to its receptor Patched 1 and activates Smoothened (SMO), thereby governing embryonic development and postnatal tissue homeostasis. Cholesterol can bind and covalently conjugate to the luminal cysteine-rich domain (CRD) of human SMO at the D95 residue (D99 in mouse). The reaction mechanism and biological function of SMO cholesterylation have not been elucidated. Here, we show that the SMO-CRD undergoes auto-cholesterylation which is boosted by calcium and involves an intramolecular ester intermediate. In cells, Hh stimulation elevates local calcium concentration in the SMO-localized endosomes through store-operated calcium entry. In addition, we identify the signaling-incompetent SMO D95E mutation, and the D95E mutant SMO can bind cholesterol but cannot be modified or activated by cholesterol. The homozygous SmoD99E/D99E knockin mice are embryonic lethal with severe developmental delay, demonstrating that cholesterylation of CRD is required for full-length SMO activation. Our work reveals the unique autocatalytic mechanism of SMO cholesterylation and an unprecedented role of calcium in Hh signaling.
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Calcio , Proteínas Hedgehog , Animales , Colesterol , Ésteres , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Ratones , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Receptor Smoothened/genética , Receptor Smoothened/metabolismoRESUMEN
Flagellin is a key bacterial virulence factor that can stimulate molecular immune signaling in both animals and plants. The detailed mechanisms of recognizing flagellin and mounting an efficient immune response have been uncovered in vertebrates; however, whether invertebrates can discriminate flagellin remains largely unknown. In the present study, the homolog of human SHOC2 leucine rich repeat scaffold protein in kuruma shrimp (Marsupenaeus japonicus), designated MjShoc2, was found to interact with Vibrio anguillarum flagellin A (FlaA) using yeast two-hybrid and pull-down assays. MjShoc2 plays a role in antibacterial response by mediating the FlaA-induced expression of certain antibacterial effectors, including lectin and antimicrobial peptide. FlaA challenge, via MjShoc2, led to phosphorylation of extracellular regulated kinase (Erk), and the subsequent activation of signal transducer and activator of transcription (Stat), ultimately inducing the expression of effectors. Therefore, by establishing the FlaA/MjShoc2/Erk/Stat signaling axis, this study revealed a new antibacterial strategy in shrimp, and provides insights into the flagellin sensing mechanism in invertebrates.
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Proteínas de Artrópodos/inmunología , Flagelina/inmunología , Péptidos y Proteínas de Señalización Intracelular/inmunología , Penaeidae/inmunología , Vibriosis/inmunología , Animales , Sistema de Señalización de MAP Quinasas/inmunología , Penaeidae/microbiología , Factores de Transcripción STAT/inmunología , VibrioRESUMEN
Riparian wetlands in permafrost regions are critical regions for hydrological, ecological, and biochemical processes. We studied the soils of riparian and transition wetlands and analyzed physicochemical properties, stoichiometry, and microbial respiration activities (microbial biomass carbon, basal respiration, microbial entropy, and metabolic entropy) of the humus layer and diffe-rent soil layers. The results showed that the main differentiation of soil physical and chemical pro-perties in riparian forest wetlands was below 20 cm. Compared to the wetlands of transition zone, total carbon content, total nitrogen content, C/P and N/P decreased significantly with soil depth in riparian forest wetlands. These changes in soil stoichiometry were mainly caused by soil nitrogen content. Such a result meant that the transferring of nitrogen was relatively fast and that there was nitrogen limitation. The main differentiation of Na, Mg, K and Ca in soil occurred in the 30 cm layer of the transition zone and the 20 cm layer of the riparian forest wetlands. The correlations between soil Mg content and total C, total N, total P contents were significant. It meant that the soil Mg was an important element to riparian wetlands in the Great Hing'an Mountains. Microbial respiration activities of the humus layer in riparian forest wetlands and transition zone were higher than those in the other soil layers, indicating that the content of labile carbon fractions was high. The correlations between soil microbial respiration activities and soil properties, stoichiometry, nutrient elements were different in riparian wetland and transition zone. Soil total nitrogen contents were significantly correlated with soil microbial respiration activities in riparian wetland, indicating that soil microbial respiration activities were limited by nitrogen in riparian wetland of the Great Hing'an Mountains.
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Hielos Perennes , Humedales , Carbono/análisis , China , Bosques , Nitrógeno/análisis , Respiración , Suelo , Microbiología del SueloRESUMEN
Drosophila Vago is a small antiviral peptide. Its ortholog in Culex mosquito was found to be an interferon-like cytokine that limits virus replication through activating Jak/Stat signaling. However, this activation is independent of Domeless, the sole homolog of vertebrate type I cytokine receptor. How Vago activates the Jak/Stat pathway remains unknown. Herein, we report this process is dependent on integrin in kuruma shrimp (Marsupenaeus japonicus). Shrimp Vago-like (MjVago-L) plays an antiviral role by activating the Jak/Stat pathway and inducing Stat-regulated Ficolin. Blocking integrin abrogates the role of MjVago-L. The interaction between MjVago-L and integrin ß3 is confirmed. An Asp residue in MjVago-L is found critical for the interaction and MjVago-L's antiviral role. Moreover, Fak, a key adaptor of integrin signaling, mediates MjVago-L-induced Jak/Stat activation. Therefore, this study reveals that integrin, as the receptor of MjVago-L, mediates Jak/Stat activation. The establishment of the MjVago-L/integrin/Fak/Jak/Stat/Ficolin axis provides insights into antiviral cytokine signaling in invertebrates.
Asunto(s)
Antivirales/metabolismo , Integrinas/metabolismo , Interferones/metabolismo , Factores de Transcripción STAT/metabolismo , Animales , Artrópodos/metabolismo , Citocinas/metabolismo , Inmunidad Innata/inmunología , Quinasas Janus/metabolismo , Receptores de Citocinas/metabolismo , Transducción de Señal/fisiologíaRESUMEN
BACKGROUND: Matrix metalloproteinase 10 (MMP-10) has a close relationship with carotid atherosclerosis (CAS) and cerebral infarction. The MMP-10 rs17435959 polymorphism causes a leucine to valine transition at codon 4 in exon 1 of the MMP-10 gene and may have functional effects. OBJECTIVES: To investigate the relationship between the MMP-10 rs17435959 polymorphism and the formation and stability of CAS plaques. MATERIALS AND METHODS: The present case-control study contains 738 visitors who came to our health examination center for the first time. According to the carotid ultrasound examinations, visitors were classified into the vulnerable plaque group (41-86 years old, 141 male, 105 female), the stable plaque group (41-86 years old, 141 male, 105 female) and the no plaque group (41-85 years old, 141 male, 105 female). All visitors in the three groups were sex- and- age-matched, and cardiovascular and cerebrovascular diseases were absent. The polymorphism was genotyped by real-time polymerase chain reaction- restriction. RESULTS: Compared to the GG genotype, the frequency of the CC and CG genotypes was significantly more common in the vulnerable plaque group than in the no plaque group (18.7% vs. 7.7%, unadjusted P = 0.002). Moreover, compared to the G allele, the frequency of the C allele was significantly more common in the vulnerable plaque group than in the no plaque group (10.4% vs. 3.9%, unadjusted P = 0.000) and in the vulnerable plaque group than in the stable plaque group (10.4% vs. 5.1%, unadjusted P = 0.008). Binary logistic regression showed that the CC and CG genotype was independent risk factor for the formation (P = 0.019, OR = 1.961, 95% CI [1.117, 3.444]) and vulnerability (P = 0.035, OR = 1.842, 95% CI [1.045, 3.247]) of CAS plaques. Moreover, individuals who have the C allele showed a higher level of fibrinogen, which was an independent risk factor for the formation of CAS plaques (P = 0.000, OR = 2.425, 95% CI [1.475, 3.985]). CONCLUSIONS: The rs17435959 polymorphism was associated with the formation and vulnerability of CAS plaques. Individuals who had variant-type MMP-10 showed higher levels of fibrinogen, which promoted the formation of CAS plaques.