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1.
J Cell Biol ; 223(2)2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38078859

RESUMO

TLR/IL-1R signaling plays a critical role in sensing various harmful foreign pathogens and mounting efficient innate and adaptive immune responses, and it is tightly controlled by intracellular regulators at multiple levels. In particular, TOLLIP forms a constitutive complex with IRAK1 and sequesters it in the cytosol to maintain the kinase in an inactive conformation under unstimulated conditions. However, the underlying mechanisms by which IRAK1 dissociates from TOLLIP to activate TLR/IL-1R signaling remain obscure. Herein, we show that BLK positively regulates TLR/IL-1R-mediated inflammatory response. BLK-deficient mice produce less inflammatory cytokines and are more resistant to death upon IL-1ß challenge. Mechanistically, BLK is preassociated with IL1R1 and IL1RAcP in resting cells. IL-1ß stimulation induces heterodimerization of IL1R1 and IL1RAcP, which further triggers BLK autophosphorylation at Y309. Activated BLK directly phosphorylates TOLLIP at Y76/86/152 and further promotes TOLLIP dissociation from IRAK1, thereby facilitating TLR/IL-1R-mediated signal transduction. Overall, these findings highlight the importance of BLK as an active regulatory component in TLR/IL-1R signaling.


Assuntos
Citocinas , Quinases Associadas a Receptores de Interleucina-1 , Transdução de Sinais , Quinases da Família src , Animais , Camundongos , Citocinas/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Interleucina-1beta/metabolismo , Fosforilação , Quinases da Família src/metabolismo
2.
PLoS Pathog ; 19(10): e1011742, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37871014

RESUMO

Viral infection triggers the activation of transcription factor IRF3, and its activity is precisely regulated for robust antiviral immune response and effective pathogen clearance. However, how full activation of IRF3 is achieved has not been well defined. Herein, we identified BLK as a key kinase that positively modulates IRF3-dependent signaling cascades and executes a pre-eminent antiviral effect. BLK deficiency attenuates RNA or DNA virus-induced ISRE activation, interferon production and the cellular antiviral response in human and murine cells, whereas overexpression of BLK has the opposite effects. BLK-deficient mice exhibit lower serum cytokine levels and higher lethality after VSV infection. Moreover, BLK deficiency impairs the secretion of downstream antiviral cytokines and promotes Senecavirus A (SVA) proliferation, thereby supporting SVA-induced oncolysis in an in vivo xenograft tumor model. Mechanistically, viral infection triggers BLK autophosphorylation at tyrosine 309. Subsequently, activated BLK directly binds and phosphorylates IRF3 at tyrosine 107, which further promotes TBK1-induced IRF3 S386 and S396 phosphorylation, facilitating sufficient IRF3 activation and downstream antiviral response. Collectively, our findings suggest that targeting BLK enhances viral clearance via specifically regulating IRF3 phosphorylation by a previously undefined mechanism.


Assuntos
Proteínas Serina-Treonina Quinases , Viroses , Humanos , Animais , Camundongos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Fator Regulador 3 de Interferon/metabolismo , Processamento de Proteína Pós-Traducional , Citocinas/metabolismo , Imunidade Inata , Quinases da Família src/metabolismo
3.
ACS Appl Mater Interfaces ; 12(22): 24806-24816, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32396331

RESUMO

The development of anion exchange membranes (AEMs) is hindered by the trade-off of ionic conductivity, alkaline stability, and mechanical properties. Tröger's base polymers (Tb-polymers) are recognized as promising membrane materials to overcome these obstacles. Herein, the AEMs made from Tb-poly(crown ether)s (Tb-PCEs) show good comprehensive performance. The influence of crown ether on the conductivity and alkaline stability of AEMs has been investigated in detail. The formation of hydronium ion-crown ether complexes and an obvious microphase-separated structure formed by the existence of crown ether can enhance the conductivity of the AEMs. The maximum OH- conductivity of 141.5 mS cm-1 is achieved from the Tb-PCEs based AEM (Tb-PCE-1) at 80 °C in ultrapure water. The ion-dipole interaction of the Na+ with crown ether can protect the quaternary ammonium from the attack of OH- to improve the alkaline stability of AEMs. After 675 h of alkaline treatment, the OH- conductivity of Tb-PCE-1 decreases by only 6%. The Tb-PCE-1-based single cell shows a peak power density of 0.202 W cm-2 at 80 °C. The prominent physicochemical properties are attributed to the well-developed microstructure of the Tb-PCEs, as revealed by TEM, AFM, and SAXS observations.

4.
Environ Monit Assess ; 191(6): 395, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31123882

RESUMO

Trace element contamination caused by mining is a serious environmental problem. The potential effects of exploiting the Yunfu pyrite mine (southern China) on soil were investigated by determining trace elements in 56 surface soil samples from the vicinity of the Yunfu pyrite mine. The samples were acid dissolved and measured by an inductively coupled plasma mass spectrometry (ICP-MS). Principal component analysis and hierarchical cluster analysis were used to identify factors influencing the trace element contents and possible sources of the trace elements. The degree of trace element pollution was determined using the geological accumulation index Igeo. Monte Carlo simulations were used to assess the health risks posed. The results show that (1) six factors (parent material, mining activities, ore composition, rainfall, terrain, and other inputs) strongly affected the trace element contents of the soil samples. (2) There were three groups of trace elements, according to their possible sources. One group (Cs, Ga, Ge, Hf, Nb, Rb, Ta, Th, Ti, U, and Zr) mainly originated in parent rocks. Another group (Cr, Ni, Sr, and V) was mainly supplied by industrial plants and traffic emissions. The third group (Ba, Co, Cu, Mn, Pb, and Zn) was mainly supplied through pyrite ore exploitation processes. (3) Some samples were slightly to moderately polluted with Cs, Ga, Ge, Nb, Rb, Ta, and Ti. Most samples were moderately to highly polluted with Ba, Co, Cu, Mn, Pb, and Zn. (4) Trace elements in soil pose strong non-carcinogenic and carcinogenic health risks to people (particularly children) living near the Yunfu pyrite mine.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Oligoelementos/análise , Criança , China , Humanos , Ferro , Mineração , Solo/química , Sulfetos
5.
J Hum Evol ; 78: 144-57, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25456822

RESUMO

The Homo erectus cranium from Gongwangling, Lantian County, Shaanxi Province is the oldest fossil hominin specimen from North China. It was found in 1964 in a layer below the Jaramillo subchron and was attributed to loess (L) L15 in the Chinese loess-palaeosol sequence, with an estimated age of ca. 1.15 Ma (millions of years ago). Here, we demonstrate that there is a stratigraphical hiatus in the Gongwangling section immediately below loess 15, and the cranium in fact lies in palaeosol (S) S22 or S23, the age of which is ca. 1.54-1.65 Ma. Closely spaced palaeomagnetic sampling at two sections at Gongwangling and one at Jiacun, 10 km to the north, indicate that the fossil layer at Gongwangling and a similar fossil horizon at Jiacun were deposited shortly before a short period of normal polarity above the Olduvai subchron. This is attributed to the Gilsa Event that has been dated elsewhere to ca. 1.62 Ma. Our investigations thus demonstrate that the Gongwangling cranium is slightly older than ca. 1.62 Ma, probably ca. 1.63 Ma, and significantly older than previously supposed. This re-dating now makes Gongwangling the second oldest site outside Africa (after Dmanisi) with cranial remains, and causes substantial re-adjustment in the early fossil hominin record in Eurasia.


Assuntos
Hominidae/anatomia & histologia , Crânio/anatomia & histologia , Animais , China , Fósseis , Paleontologia , Datação Radiométrica
6.
Genomics ; 99(5): 315-21, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22425900

RESUMO

Freshwater planarian flatworm possesses an extraordinary ability to regenerate lost body parts after amputation; it is perfect organism model in regeneration and stem cell biology. Recently, small RNAs have been an increasing concern and studied in many aspects, including regeneration and stem cell biology, among others. In the current study, the large-scale cloning and sequencing of sRNAs from the intact and regenerative planarian Dugesia japonica are reported. Sequence analysis shows that sRNAs between 18nt and 40nt are mainly microRNAs and piRNAs. In addition, 209 conserved miRNAs and 12 novel miRNAs are identified. Especially, a better screening target method, negative-correlation relationship of miRNAs and mRNA, is adopted to improve target prediction accuracy. Similar to miRNAs, a diverse population of piRNAs and changes in the two samples are also listed. The present study is the first to report on the important role of sRNAs during planarian Dugesia japonica regeneration.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Planárias/genética , RNA de Helmintos/genética , Pequeno RNA não Traduzido/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Perfilação da Expressão Gênica , Genoma Helmíntico/genética , MicroRNAs/genética , Dados de Sequência Molecular , Planárias/fisiologia , RNA Interferente Pequeno/genética , Regeneração/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Mol Biol Rep ; 39(3): 2653-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21713409

RESUMO

MicroRNAs (miRNAs) are ~22-nt small non-coding RNAs that regulate the expression of specific target genes in many eukaryotes. miRNAs have been shown to play important roles in stem cell maintenance, cell fate determination, and differentiation. Planarians are capable of regenerating entire body plans from tiny fragments; this regenerative capacity is facilitated by a population of pluripotent stem cells known as neoblasts. Planarians have been a classic model system for the study of many aspects of stem cell biology. However, very limited knowledge on miRNA involved in this regulatory mechanism exists. This study profiles the expression of miRNAs in the normal and regenerative tissues of planarians using miRCURY LNA array technology. Thirteen miRNAs showed significant differences in expression between these two tissues. To further confirm our results, we examined the expression of two miRNAs by qRT-PCR. Results show that some known miRNAs may play key roles in the regulatory mechanisms of regeneration. Our findings can be utilized in future research on miRNA function.


Assuntos
MicroRNAs/genética , Planárias/genética , Células-Tronco Pluripotentes/metabolismo , Regeneração/genética , Animais , Biologia Computacional , Primers do DNA/genética , MicroRNAs/metabolismo , Análise em Microsséries , Planárias/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
8.
Protein J ; 30(4): 247-52, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21479991

RESUMO

Fibrolase is a non-hemorrhagic zinc metalloproteinase found in southern copperhead snake (Agkistrodon contortrix contortrix) venom that acts directly on fibrin clots and does not require plasminogen or any other blood-borne intermediate for activity. Chimeras of fibrolase with RGD peptides conferring antiplatelet activity have been synthesized covalently, but we describe a simpler, cheaper and less toxic method, using site-directed mutagensis. Fibrolase variants that constitute the arginine-glycine-aspartic acid (Arg-Gly-Asp, RGD) motif were constructed using site-directed mutagenesis. Chimeric genes of fibrolase were expressed in Escherichia coli to obtain the bifunctional chimeric molecule of fibrolase that can inhibit platelet aggregation. After refolding and purification, platelet-targeted thrombolysis and antiplatelet aggregation of the target chimeric protein were determined. The mutant RGD-F2, using the GPRGDWRMLG peptide to replace the TSVSHD sequence between sites 69 and 72, not only had almost the same catalytic ability as wild-type fibrolase but also a strong ability to inhibit platelet aggregation.


Assuntos
Agkistrodon/genética , Fibrinolíticos/farmacologia , Metaloendopeptidases/genética , Metaloendopeptidases/farmacologia , Oligopeptídeos/genética , Inibidores da Agregação Plaquetária/farmacologia , Sequência de Aminoácidos , Animais , Escherichia coli/genética , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/metabolismo , Expressão Gênica , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/metabolismo , Redobramento de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência
9.
Genomics ; 97(6): 364-71, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21333733

RESUMO

Planarians exhibit an extraordinary ability to regenerate lost body parts which is attributed to an abundance of pluripotent somatic stem cells called neoblasts. In this article, we report a transcriptome sequence of a Planaria subspecies Dugesia japonica derived by high-throughput sequencing. In addition, we researched transcriptome changes during different periods of regeneration by using a tag-based digital gene expression (DGE) system. Consequently, 11,913,548 transcriptome sequencing reads were obtained. Finally, these reads were eventually assembled into 37,218 unique unigenes. These assembled unigenes were annotated with various methods. Transcriptome changes during planarian regeneration were investigated by using a tag-based DGE system. We obtained a sequencing depth of more than 3.5million tags per sample and identified a large number of differentially expressed genes at various stages of regeneration. The results provide a fairly comprehensive molecular biology background to the research on planarian development, particularly with regard to its regeneration progress.


Assuntos
Perfilação da Expressão Gênica , Planárias/genética , Regeneração/genética , Animais , Mapeamento Cromossômico/métodos , Genes de Helmintos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Fases de Leitura Aberta , Análise de Sequência de DNA/métodos
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