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1.
Mol Cell ; 74(3): 494-507.e8, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30930054

RESUMO

N6-methyladenosine (m6A) is the most abundant internal modification in RNAs and plays regulatory roles in a variety of biological and physiological processes. Despite its important roles, the molecular mechanism underlying m6A-mediated gene regulation is poorly understood. Here, we show that m6A-containing RNAs are subject to endoribonucleolytic cleavage via YTHDF2 (m6A reader protein), HRSP12 (adaptor protein), and RNase P/MRP (endoribonucleases). We demonstrate that HRSP12 functions as an adaptor to bridge YTHDF2 and RNase P/MRP, eliciting rapid degradation of YTHDF2-bound RNAs. Transcriptome-wide analyses show that m6A RNAs that are preferentially targeted for endoribonucleolytic cleavage have an HRSP12-binding site and a RNase P/MRP-directed cleavage site upstream and downstream of the YTHDF2-binding site, respectively. We also find that a subset of m6A-containing circular RNAs associates with YTHDF2 in an HRSP12-dependent manner and is selectively downregulated by RNase P/MRP. Thus, our data expand the known functions of RNase P/MRP to endoribonucleolytic cleavage of m6A RNAs.


Assuntos
Adenosina/análogos & derivados , Proteínas de Choque Térmico/genética , Estabilidade de RNA/genética , Proteínas de Ligação a RNA/genética , Ribonuclease P/genética , Ribonucleases/genética , Adenosina/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Sítios de Ligação/genética , Escherichia coli/genética , Regulação da Expressão Gênica/genética , Células HeLa , Humanos , Metiltransferases/genética , RNA/genética , Processamento Pós-Transcricional do RNA/genética , RNA Circular , Transcriptoma/genética
2.
Genes Dev ; 30(18): 2093-2105, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27798850

RESUMO

Glucocorticoid (GC) receptor (GR) has been shown recently to bind a subset of mRNAs and elicit rapid mRNA degradation. However, the molecular details of GR-mediated mRNA decay (GMD) remain unclear. Here, we demonstrate that GMD triggers rapid degradation of target mRNAs in a translation-independent and exon junction complex-independent manner, confirming that GMD is mechanistically distinct from nonsense-mediated mRNA decay (NMD). Efficient GMD requires PNRC2 (proline-rich nuclear receptor coregulatory protein 2) binding, helicase ability, and ATM-mediated phosphorylation of UPF1 (upstream frameshift 1). We also identify two GMD-specific factors: an RNA-binding protein, YBX1 (Y-box-binding protein 1), and an endoribonuclease, HRSP12 (heat-responsive protein 12). In particular, using HRSP12 variants, which are known to disrupt trimerization of HRSP12, we show that HRSP12 plays an essential role in the formation of a functionally active GMD complex. Moreover, we determine the hierarchical recruitment of GMD factors to target mRNAs. Finally, our genome-wide analysis shows that GMD targets a variety of transcripts, implicating roles in a wide range of cellular processes, including immune responses.


Assuntos
Monócitos/metabolismo , Estabilidade de RNA/fisiologia , Receptores de Glucocorticoides/metabolismo , Adenosina Trifosfatases/metabolismo , Quimiocina CCL2/metabolismo , Quimiotaxia/genética , Células HEK293 , Células HeLa , Proteínas de Choque Térmico/metabolismo , Humanos , Monócitos/enzimologia , Monócitos/imunologia , Fosforilação , Polimerização , RNA Helicases , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Ribonucleases/metabolismo , Transativadores/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo
3.
Trends Genet ; 36(3): 177-188, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31964509

RESUMO

N6-Methyladenosine (m6A), the most prevalent internal modification associated with eukaryotic mRNAs, influences many steps of mRNA metabolism, including splicing, export, and translation, as well as stability. Recent studies have revealed that m6A-containing mRNAs undergo one of two distinct pathways of rapid degradation: deadenylation via the YT521-B homology (YTH) domain-containing family protein 2 (YTHDF2; an m6A reader protein)-CCR4/NOT (deadenylase) complex or endoribonucleolytic cleavage by the YTHDF2-HRSP12-ribonuclease (RNase) P/mitochondrial RNA-processing (MRP) (endoribonuclease) complex. Some m6A-containing circular RNAs (circRNAs) are also subject to endoribonucleolytic cleavage by YTHDF2-HRSP12-RNase P/MRP. Here, we highlight recent progress on the molecular mechanisms underlying rapid mRNA degradation via m6A and describe our current understanding of the dynamic regulation of m6A-mediated mRNA decay through the crosstalk between m6A (or YTHDF2) and other cellular factors.


Assuntos
Adenosina/análogos & derivados , Estabilidade de RNA/genética , Proteínas de Ligação a RNA/genética , Adenosina/genética , Proteínas de Choque Térmico/genética , Humanos , Proteínas do Tecido Nervoso/genética , Ligação Proteica/genética , Domínios Proteicos/genética , Fatores de Processamento de RNA/genética , RNA Mensageiro/genética , Ribonuclease P/genética , Ribonucleases/genética
4.
Immunity ; 38(4): 681-93, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23562159

RESUMO

How innate lymphoid cells (ILCs) in the thymus and gut become specialized effectors is unclear. The prototypic innate-like γδ T cells (Tγδ17) are a major source of interleukin-17 (IL-17). We demonstrate that Tγδ17 cells are programmed by a gene regulatory network consisting of a quartet of high-mobility group (HMG) box transcription factors, SOX4, SOX13, TCF1, and LEF1, and not by conventional TCR signaling. SOX4 and SOX13 directly regulated the two requisite Tγδ17 cell-specific genes, Rorc and Blk, whereas TCF1 and LEF1 countered the SOX proteins and induced genes of alternate effector subsets. The T cell lineage specification factor TCF1 was also indispensable for the generation of IL-22 producing gut NKp46(+) ILCs and restrained cytokine production by lymphoid tissue inducer-like effectors. These results indicate that similar gene network architecture programs innate sources of IL-17, independent of anatomical origins.


Assuntos
Proteínas de Grupo de Alta Mobilidade/metabolismo , Interleucina-17/biossíntese , Intestinos/imunologia , Subpopulações de Linfócitos/imunologia , Linfócitos T/imunologia , Animais , Antígenos Ly/metabolismo , Autoantígenos/genética , Autoantígenos/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Redes Reguladoras de Genes/imunologia , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Proteínas de Grupo de Alta Mobilidade/genética , Imunidade Inata/genética , Interleucina-17/genética , Interleucinas/imunologia , Fator 1 de Ligação ao Facilitador Linfoide/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Transdução de Sinais/imunologia , Ativação Transcricional/imunologia , Interleucina 22
5.
Knee Surg Sports Traumatol Arthrosc ; 29(11): 3724-3734, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33392699

RESUMO

PURPOSE: To compare clinical outcomes between the conventional round and rectangular tunnel techniques in single-bundle posterior cruciate ligament (PCL) reconstruction. METHODS: Twenty-seven and 108 patients who underwent PCL reconstructions using a rectangular dilator (Group 1) and rounded tunnel reamer (Group 2), respectively, were included. The exclusion criteria were having a concomitant fracture, osteotomy, subtotal or total meniscectomy, and no remnant PCL tissue. A 4:1 propensity score matching was performed. The knee laxity on stress radiography, International Knee Documentation Committee Subjective Knee Evaluation score, Tegner activity score and Orthopädische Arbeitsgruppe Knie score were evaluated. RESULTS: No significant differences were found between the groups in terms of clinical scores. (n.s.) The mean posterior translations were also not significantly different between the Group 1 and 2 (3.6 ± 2.8 and 3.8. ± 3.1 mm, respectively; n.s.). However, 3 patients (11.1%) in Group 1 and 15 patients (13.8%) in Group 2 showed posterior translation of > 5 mm. The combined posterolateral corner sling technique was performed for 27 patients (100%) in Group 1 and for 96 patients (88.9%) in Group 2. We found no significant difference in rotational stability at the final follow-up. One patient was found to have a femoral condyle fracture during rectangular femoral tunnel establishment, which was healed after screw fixation, without laxity, during follow-up. The intra- and inter-observer reliabilities of the radiological measurements ranged from 0.81 to 0.89. CONCLUSION: Arthroscopic anatomical remnant-preserving PCL reconstruction using a rectangular dilator showed satisfactory clinical results and stability as compared with PCL reconstruction using a conventional rounded reamer. Rectangular tunnel technique in PCL reconstruction could be a good treatment option with theoretical advantage to be anatomic. LEVEL OF EVIDENCE: Level IV.


Assuntos
Traumatismos do Joelho , Reconstrução do Ligamento Cruzado Posterior , Ligamento Cruzado Posterior , Seguimentos , Humanos , Traumatismos do Joelho/cirurgia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Ligamento Cruzado Posterior/cirurgia , Resultado do Tratamento
6.
FASEB J ; 33(2): 2680-2693, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30303743

RESUMO

All metazoan mRNAs have a poly(A) tail at the 3' end with the exception of replication-dependent histone (RDH) mRNAs, which end in a highly conserved stem-loop (SL) structure. However, a subset of RDH mRNAs are reported to be polyadenylated under physiologic conditions. The molecular details of the biogenesis of polyadenylated RDH [poly(A)+ RDH] mRNAs remain unknown. In this study, our genome-wide analyses reveal that puromycin treatment or UVC irradiation stabilizes poly(A)+ RDH mRNAs, relative to canonical RDH mRNAs, which end in an SL structure. We demonstrate that the stabilization of poly(A)+ RDH mRNAs occurs in a translation-independent manner and is regulated via human antigen R (HuR) binding to the extended 3' UTR under stress conditions. Our data suggest that HuR regulates the expression of poly(A)+ RDH mRNAs.-Ryu, I., Park, Y., Seo, J.-W., Park, O. H., Ha, H., Nam, J.-W., Kim, Y. K. HuR stabilizes a polyadenylated form of replication-dependent histone mRNAs under stress conditions.


Assuntos
Replicação do DNA , Proteína Semelhante a ELAV 1/metabolismo , Regulação Neoplásica da Expressão Gênica , Histonas/genética , Poliadenilação , RNA Mensageiro/genética , Estresse Fisiológico , Proteína Semelhante a ELAV 1/genética , Células HeLa , Histonas/metabolismo , Humanos , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Transcrição Gênica
7.
Proc Natl Acad Sci U S A ; 112(13): E1540-9, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25775514

RESUMO

Glucocorticoid receptor (GR), which was originally known to function as a nuclear receptor, plays a role in rapid mRNA degradation by acting as an RNA-binding protein. The mechanism by which this process occurs remains unknown. Here, we demonstrate that GR, preloaded onto the 5'UTR of a target mRNA, recruits UPF1 through proline-rich nuclear receptor coregulatory protein 2 (PNRC2) in a ligand-dependent manner, so as to elicit rapid mRNA degradation. We call this process GR-mediated mRNA decay (GMD). Although GMD, nonsense-mediated mRNA decay (NMD), and staufen-mediated mRNA decay (SMD) share upstream frameshift 1 (UPF1) and PNRC2, we find that GMD is mechanistically distinct from NMD and SMD. We also identify de novo cellular GMD substrates using microarray analysis. Intriguingly, GMD functions in the chemotaxis of human monocytes by targeting chemokine (C-C motif) ligand 2 (CCL2) mRNA. Thus, our data provide molecular evidence of a posttranscriptional role of the well-studied nuclear hormone receptor, GR, which is traditionally considered a transcription factor.


Assuntos
Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Glucocorticoides/metabolismo , Transativadores/metabolismo , Quimiocina CCL2/metabolismo , Quimiotaxia , Genes Reporter , Células HEK293 , Células HeLa , Humanos , Ligantes , Monócitos/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido , Ligação Proteica , RNA Helicases , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
8.
Proc Natl Acad Sci U S A ; 111(43): E4577-86, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25313076

RESUMO

It has long been considered that intron-containing (spliced) mRNAs are translationally more active than intronless mRNAs (identical mRNA not produced by splicing). The splicing-dependent translational enhancement is mediated, in part, by the exon junction complex (EJC). Nonetheless, the molecular mechanism by which each EJC component contributes to the translational enhancement remains unclear. Here, we demonstrate the previously unappreciated role of eukaryotic translation initiation factor 4AIII (eIF4AIII), a component of EJC, in the translation of mRNAs bound by the nuclear cap-binding complex (CBC), a heterodimer of cap-binding protein 80 (CBP80) and CBP20. eIF4AIII is recruited to the 5'-end of mRNAs bound by the CBC by direct interaction with the CBC-dependent translation initiation factor (CTIF); this recruitment of eIF4AIII is independent of the presence of introns (deposited EJCs after splicing). Polysome fractionation, tethering experiments, and in vitro reconstitution experiments using recombinant proteins show that eIF4AIII promotes efficient unwinding of secondary structures in 5'UTR, and consequently enhances CBC-dependent translation in vivo and in vitro. Therefore, our data provide evidence that eIF4AIII is a specific translation initiation factor for CBC-dependent translation.


Assuntos
Regiões 5' não Traduzidas/genética , Núcleo Celular/metabolismo , Fator de Iniciação 4A em Eucariotos/metabolismo , Conformação de Ácido Nucleico , Biossíntese de Proteínas , Capuzes de RNA/metabolismo , Replicação do DNA , Regulação para Baixo , Fatores de Iniciação em Eucariotos/metabolismo , Células HEK293 , Células HeLa , Histonas/metabolismo , Humanos , Íntrons/genética , Modelos Biológicos , Ligação Proteica , Splicing de RNA/genética , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo
9.
Dev Dyn ; 244(1): 43-55, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25329411

RESUMO

BACKGROUND: Among the complexities of skeletal muscle differentiation is a temporal distinction in the onset of expression of different lineage-specific genes. The lineage-determining factor MyoD is bound to myogenic genes at the onset of differentiation whether gene activation is immediate or delayed. How temporal regulation of differentiation-specific genes is established remains unclear. RESULTS: Using embryonic tissue, we addressed the molecular differences in the organization of the myogenin and muscle creatine kinase (MCK) gene promoters by examining regulatory factor binding as a function of both time and spatial organization during somitogenesis. At the myogenin promoter, binding of the homeodomain factor Pbx1 coincided with H3 hyperacetylation and was followed by binding of co-activators that modulate chromatin structure. MyoD and myogenin binding occurred subsequently, demonstrating that Pbx1 facilitates chromatin remodeling and modification before myogenic regulatory factor binding. At the same time, the MCK promoter was bound by HDAC2 and MyoD, and activating histone marks were largely absent. The association of HDAC2 and MyoD was confirmed by co-immunoprecipitation, proximity ligation assay (PLA), and sequential ChIP. CONCLUSIONS: MyoD differentially promotes activated and repressed chromatin structures at myogenic genes early after the onset of skeletal muscle differentiation in the developing mouse embryo.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/embriologia , Proteína MyoD/metabolismo , Regiões Promotoras Genéticas/fisiologia , Animais , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Histona Desacetilase 2/biossíntese , Histona Desacetilase 2/genética , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Camundongos , Músculo Esquelético/citologia , Fator de Transcrição 1 de Leucemia de Células Pré-B , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
10.
Aesthet Surg J ; 36(9): 977-82, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27025245

RESUMO

BACKGROUND: The marginal mandibular branch (Mbr) of the facial nerve is vulnerable to damage during rhytidoplasty, surgical reduction of the mandibular angle, parotidectomy, and excision of the submandibular gland. OBJECTIVES: The authors sought to map the Mbr and determine the relationship between the number of Mbr offshoots and the course of the Mbr. METHODS: The Mbr was examined in 29 hemifaces from 12 embalmed and 4 fresh cadavers (10 males, 6 females; mean age, 73.7 years). RESULTS: The Mbr was located ≤5 mm from the gonion (Go) in 24 of 29 hemifaces (82.8%) and ≤10 mm from the intersection of the facial artery and mandible (ie, FM) in 26 hemifaces (89.7%). In 16 hemifaces (55.2%), offshoots arose from the Mbr inferior to the mandible. The Mbr ran below the Go in 14 hemifaces (48.3%) and ran below FM in 13 hemifaces (44.8%). Except for minute offshoots deep to the platysma, the Mbr was not found to pass >2 cm below the mandible. The mean (± standard deviation) quantity of Mbr offshoots was 1.5 (± 0.6). A greater number of offshoots was associated with a higher likelihood of an inferiorly located nerve. The Mbr proceeded under the lower border of the mandible in 13 hemifaces (44.8%) and reached the mandible at a mean distance of 33.1±5.2 mm anterior to the Go. CONCLUSIONS: To avoid damaging the Mbr, surgical maneuvers should be positioned 4.5 cm anterior to the Go and 2 cm below the mandible.


Assuntos
Nervo Facial/anatomia & histologia , Mandíbula/inervação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mandíbula/anatomia & histologia , Nervo Mandibular/anatomia & histologia , Pessoa de Meia-Idade
11.
J Virol ; 88(17): 9490-503, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24942579

RESUMO

UNLABELLED: Virus-specific CD8+ T cells in the lymphoid organs contract at the resolution of virus infections by apoptosis or by dissemination into peripheral tissues, and those residing in nonlymphoid organs, including the peritoneal cavity and fat pads, are more resistant to apoptosis than those in the spleen and lymph nodes. This stability of memory T cells in the nonlymphoid tissues may enhance protection to secondary challenges. Here, we show that lymphocytic choriomeningitis virus (LCMV)-specific CD8+ T cells in nonlymphoid tissues were enriched for memory precursors (expressing high levels of interleukin-7 receptor and low levels of killer cell lectin-like receptor G1 [IL-7Rhi KLRG1lo]) and had higher expression of CD27, CXCR3, and T cell factor-1 (TCF-1), each a marker that is individually correlated with decreased apoptosis. CD8+ T cells in the peritoneal cavity of TCF-1-deficient mice had decreased survival, suggesting a role for TCF-1 in promoting survival in the nonlymphoid tissues. CXCR3+ CD8+ T cells resisted apoptosis and accumulated in the lymph nodes of mice treated with FTY720, which blocks the export of lymph node cells into peripheral tissue. The peritoneal exudate cells (PEC) expressed increased amounts of CXCR3 ligands, CXCL9 and CXCL10, which may normally recruit these nonapoptotic cells from the lymph nodes. In addition, adoptive transfer of splenic CD8+ T cells into PEC or spleen environments showed that the peritoneal environment promoted survival of CD8+ T cells. Thus, intrinsic stability of T cells which are present in the nonlymphoid tissues along with preferential migration of apoptosis-resistant CD8+ T cells into peripheral sites and the availability of tissue-specific factors that enhance memory cell survival may collectively account for the tissue-dependent apoptotic differences. IMPORTANCE: Most infections are initiated at nonlymphoid tissue sites, and the presence of memory T cells in nonlymphoid tissues is critical for protective immunity in various viral infection models. Virus-specific CD8+ T cells in the nonlymphoid tissues are more resistant to apoptosis than those in lymphoid organs during the resolution and memory phase of the immune response to acute LCMV infection. Here, we investigated the mechanisms promoting stability of T cells in the nonlymphoid tissues. This increased resistance to apoptosis of virus-specific CD8+ T cells in nonlymphoid tissues was due to several factors. Nonlymphoid tissues were enriched in memory phenotype CD8+ T cells, which were intrinsically resistant to apoptosis irrespective of the tissue environment. Furthermore, apoptosis-resistant CD8+ T cells preferentially migrated into the nonlymphoid tissues, where the availability of tissue-specific factors may enhance memory cell survival. Our findings are relevant for the generation of long-lasting vaccines providing protection at peripheral infection sites.


Assuntos
Estruturas Animais/imunologia , Apoptose , Infecções por Arenaviridae/imunologia , Linfócitos T CD8-Positivos/fisiologia , Vírus da Coriomeningite Linfocítica/imunologia , Subpopulações de Linfócitos T/fisiologia , Estruturas Animais/patologia , Animais , Antígenos de Superfície/análise , Infecções por Arenaviridae/patologia , Linfócitos T CD8-Positivos/química , Linfócitos T CD8-Positivos/imunologia , Sobrevivência Celular , Masculino , Camundongos Endogâmicos C57BL , Subpopulações de Linfócitos T/química , Subpopulações de Linfócitos T/imunologia
12.
J Immunol ; 190(6): 2659-69, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23378428

RESUMO

The Tec family tyrosine kinase, Itk, regulates signaling downstream of the TCR. The absence of Itk in CD4(+) T cells results in impaired Th2 responses along with defects in maturation, cytokine production, and survival of iNKT cells. Paradoxically, Itk(-/-) mice have spontaneously elevated serum IgE levels, resulting from an expansion of the Vγ1.1(+)Vδ6.3(+) subset of γδ T cells, known as γδ NKT cells. Comparisons between γδ NKT cells and αß iNKT cells showed convergence in the pattern of cell surface marker expression, cytokine profiles, and gene expression, suggesting that these two subsets of NKT cells undergo similar differentiation programs. Hepatic γδ NKT cells have an invariant TCR and are derived predominantly from fetal progenitors that expand in the thymus during the first weeks of life. The adult thymus contains these invariant γδ NKT cells plus a heterogeneous population of Vγ1.1(+)Vδ6.3(+) T cells with diverse CDR3 sequences. This latter population, normally excluded from the liver, escapes the thymus and homes to the liver when Itk is absent. In addition, Itk(-/-) γδ NKT cells persistently express high levels of Zbtb16 (PLZF) and Il4, genes that are normally downregulated in the most mature subsets of NKT cells. These data indicate that Itk signaling is required to prevent the expansion of γδ NKT cells in the adult thymus, to block their emigration, and to promote terminal NKT cell maturation.


Assuntos
Diferenciação Celular/imunologia , Senescência Celular/imunologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Proteínas Tirosina Quinases/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/biossíntese , Timo/enzimologia , Timo/imunologia , Animais , Inibição de Migração Celular/imunologia , Movimento Celular/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células T Matadoras Naturais/citologia , Timo/citologia
13.
Biochim Biophys Acta ; 1829(12): 1276-87, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24185201

RESUMO

Suppressor of morphogenesis in genitalia 1 (SMG1), a member of the phosphatidylinositol 3-kinase-related kinase family, is involved in nonsense-mediated mRNA decay (NMD). SMG1 phosphorylates Upf1, a key NMD factor. Subsequently, hyperphosphorylated Upf1 associates with SMG5-7 or proline-rich nuclear receptor coregulatory protein (PNRC2) to elicit rapid mRNA degradation. Upf1 is also known to be involved in staufen 1 (Stau1)-mediated mRNA decay (SMD), which is closely related to NMD. However, the biological and molecular roles of SMG1 in SMD remain unknown. Here, we provide evidence that SMG1 is involved in SMD. The immunoprecipitation results show that SMG1 is complexed with Stau1, Upf1, and Dcp1a. Downregulation of SMG1 or overexpression of a kinase-inactive mutant of SMG1 inhibits SMD efficiency. In addition, downregulation of SMG1 inhibits rapid degradation elicited by artificially tethered Stau1 or Upf1 downstream of the normal termination codon. Furthermore, Stau1 and Upf1 colocalize in processing bodies in an SMG1-dependent manner. We also find that the level of SMG1 increases during adipogenesis. Accordingly, downregulation of SMG1 causes the reduction in the level of Upf1 phosphorylation and delays adipogenesis, suggesting the functional involvement of SMG1 in adipogenesis via SMD.


Assuntos
Adipogenia/fisiologia , Proteínas do Citoesqueleto/metabolismo , Endorribonucleases/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Estabilidade de RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Células 3T3-L1 , Animais , Western Blotting , Proteínas do Citoesqueleto/genética , Regulação para Baixo , Endorribonucleases/genética , Células HEK293 , Células HeLa , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Camundongos , Fosfatidilinositol 3-Quinases/genética , Fosforilação , Proteínas Serina-Treonina Quinases , RNA Helicases , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/genética
14.
J Sleep Res ; 21(5): 546-51, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22494030

RESUMO

Previous studies have reported a relationship between short sleep duration and childhood overweight. Although school-aged children tend to compensate for weekday sleep deficit by increasing weekend sleep duration, the association between weekend catch-up sleep and childhood overweight remains unclear. This study aimed to examine the relationship between weekend catch-up sleep and being overweight in children. A total of 936 school children (48.2% boys) aged 10 or 11 years participated in this school-based cohort study. Anthropometric measurements including height and body weight were carried out. We obtained data on sleep patterns, lifestyle and parent characteristics using questionnaires. The main outcome measure was childhood overweight. After adjusting for the relevant confounding variables (age, sex, breakfast eating, screen time and parental obesity), longer sleep on weekdays and weekends was associated with decreased odds of childhood overweight (OR: 0.68; 95% CI: 0.54-0.86; OR: 0.64; 95% CI: 0.53-0.77, respectively). Participants with increased catch-up sleep duration during weekends also had decreased odds of being overweight (OR: 0.67; 95% CI: 0.53-0.85). There was an interaction between weekday sleep duration and weekend catch-up sleep in relation to childhood overweight, and this effect of weekend catch-up sleep on being overweight was stronger as the participants slept less on weekdays (P = 0.024). These results indicate that weekend catch-up sleep is independently associated with decreased risk of being overweight in fifth-grade students, and this effect can be varied by the weekday sleep duration. A prospective study is required to confirm this observation.


Assuntos
Sobrepeso/prevenção & controle , Sobrepeso/fisiopatologia , Privação do Sono/prevenção & controle , Privação do Sono/fisiopatologia , Sono/fisiologia , Adulto , Desjejum , Criança , Feminino , Humanos , Masculino , Obesidade/fisiopatologia , Obesidade/prevenção & controle , Razão de Chances , Pais , Inquéritos e Questionários
15.
Bioorg Med Chem Lett ; 22(12): 4133-8, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22578458
16.
Food Sci Biotechnol ; 31(4): 475-482, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35464246

RESUMO

Korean fermented soybean products doenjang, ganjang, and gochujang are vulnerable to contamination with aflatoxigenic fungi in the open fermentation environment. Therefore, simple and effective methods to determine aflatoxins (AFs) in these complex food matrices are needed. High-performance liquid chromatography with fluorescence detection using two derivatization methods for AF determination in three fermented soybean products was optimized and validated. Pre-column derivatization (preCD) of the AF extracts was performed using trifluoroacetic acid, and post-column derivatization (PCD) was performed in a photochemical reactor for enhanced detection. Both derivatization methods resulted in acceptable performances for linearity (R2 > 0.999), recovery (71-118%), and precision (< 10.6%) values. Recovery and precision with preCD and PCD were similar, but the limit of detection was superior with PCD. When these analytical methods were applied to commercially available fermented soybean products, the AF levels of all commercial products were ranged from not detected to 6.06 µg/kg.

17.
J Immunol ; 182(6): 3380-9, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19265115

RESUMO

The maturation of naive CD8(+) T cells into effector CTLs is a critical feature of a functional adaptive immune system. Development of CTLs depends, in part, upon the expression of the transcriptional regulator eomesodermin (EOMES), which is thought to regulate expression of two key effector molecules, perforin and granzyme B. Although EOMES is important for effector CTL development, the precise mechanisms regulating CD8(+) effector cell maturation remains poorly understood. In this study, we show that Notch1 regulates the expression of EOMES, perforin, and granzyme B through direct binding to the promoters of these crucial effector molecules. By abrogating Notch signaling, both biochemically as well as genetically, we conclude that Notch activity mediates CTL activity through direct regulation of EOMES, perforin, and granzyme B.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citotoxicidade Imunológica , Receptor Notch1/fisiologia , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/fisiologia , Animais , Diferenciação Celular/imunologia , Granzimas/antagonistas & inibidores , Granzimas/genética , Granzimas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Perforina/antagonistas & inibidores , Perforina/genética , Perforina/metabolismo , Regiões Promotoras Genéticas/imunologia , Ligação Proteica/imunologia , Receptor Notch1/antagonistas & inibidores , Receptor Notch1/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Proteínas com Domínio T/antagonistas & inibidores , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
18.
Ann Transl Med ; 9(2): 178, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33569480

RESUMO

Bosworth fracture-dislocation of ankle is a rare and irreducible type of ankle injury, with a high incidence of complication. This type of fracture was defined originally as entrapment of the proximal fragment of the fibula behind the posterior tubercle of the distal tibia. Recently, many variants of this type of fracture dislocation have been reported, but all of those reports included the syndesmosis ligament injury of ankle. Here, we report a case of a particularly rare variant of Bosworth fracture-dislocation without syndesmosis ligament injury of ankle. A 48-year-old male presented with a Bosworth fracture dislocation with entrapment of proximal fragment behind the tibia. After temporary treatment in emergency department was applied, emergency open reduction and internal fixation with a plate and screws was performed due to irreducibility of the fracture fragment. The fractured lateral malleolus was entrapped behind the tibia and rupture of the interosseous ligament was found intraoperatively. The anterior inferior tibiofibular ligament, a part of syndesmosis ligament of ankle, was grossly intact and no abnormal findings was seen by fluoroscopy with external rotational stress. Moreover, the deltoid ligament was found to be normal in ultrasonography. There were no complications after surgery and the patient showed full functional recovery at 2 years follow up. These fractures will frequently be irreducible and should be considered for open reduction and internal fixation with the careful evaluation of injury mechanisms with syndesmotic stability.

19.
PLoS One ; 16(1): e0245446, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33444365

RESUMO

The resveratrol-producing rice (Oryza sativa L.) inbred lines, Iksan 515 (I.515) and Iksan 526 (I.526), developed by the expression of the groundnut (Arachis hypogaea) resveratrol synthase 3 (AhRS3) gene in the japonica rice cultivar Dongjin, accumulated both resveratrol and its glucoside, piceid, in seeds. Here, we investigated the effect of the AhRS3 transgene on the expression of endogenous piceid biosynthesis genes (UGTs) in the developing seeds of the resveratrol-producing rice inbred lines. Ultra-performance liquid chromatography (UPLC) analysis revealed that I.526 accumulates significantly higher resveratrol and piceid in seeds than those in I.515 seeds and, in I.526 seeds, the biosynthesis of resveratrol and piceid reached peak levels at 41 days after heading (DAH) and 20 DAH, respectively. Furthermore, RNA-seq analysis showed that the expression patterns of UGT genes differed significantly between the 20 DAH seeds of I.526 and those of Dongjin. Quantitative real-time PCR (RT-qPCR) analyses confirmed the data from RNA-seq analysis in seeds of Dongjin, I.515 and I.526, respectively, at 9 DAH, and in seeds of Dongjin and I.526, respectively, at 20 DAH. A total of 245 UGTs, classified into 31 UGT families, showed differential expression between Dongjin and I.526 seeds at 20 DAH. Of these, 43 UGTs showed more than 2-fold higher expression in I.526 seeds than in Dongjin seeds. In addition, the expression of resveratrol biosynthesis genes (PAL, C4H and 4CL) was also differentially expressed between Dongjin and I.526 developing seeds. Collectively, these data suggest that AhRS3 altered the expression pattern of UGT genes, and PAL, C4H and 4CL in developing rice seeds.


Assuntos
Aciltransferases/metabolismo , Arachis/enzimologia , Glicosiltransferases/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Resveratrol/metabolismo , Difosfato de Uridina/metabolismo , Aciltransferases/genética , Glicosiltransferases/genética , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Transgenes
20.
Nat Commun ; 12(1): 97, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397978

RESUMO

Globally, soybean is a major protein and oil crop. Enhancing our understanding of the soybean domestication and improvement process helps boost genomics-assisted breeding efforts. Here we present a genome-wide variation map of 10.6 million single-nucleotide polymorphisms and 1.4 million indels for 781 soybean individuals which includes 418 domesticated (Glycine max), 345 wild (Glycine soja), and 18 natural hybrid (G. max/G. soja) accessions. We describe the enhanced detection of 183 domestication-selective sweeps and the patterns of putative deleterious mutations during domestication and improvement. This predominantly selfing species shows 7.1% reduction of overall deleterious mutations in domesticated soybean relative to wild soybean and a further 1.4% reduction from landrace to improved accessions. The detected domestication-selective sweeps also show reduced levels of deleterious alleles. Importantly, genotype imputation with this resource increases the mapping resolution of genome-wide association studies for seed protein and oil traits in a soybean diversity panel.


Assuntos
Domesticação , Glycine max/genética , Mutação/genética , Cromossomos de Plantas/genética , Bases de Dados Genéticas , Variação Genética , Genética Populacional , Genoma de Planta , Estudo de Associação Genômica Ampla , Haplótipos/genética , Filogenia , Seleção Genética
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