RESUMO
Endothelial cells (ECs) respond to blood shear stress by changing their morphology is important for maintaining vascular homeostasis. Studies have documented a relationship between endothelial cell shape and the stress flow, and however, the mechanism underlying this cytoskeletal rearrangement due to shear stress remains uncertain. In this paper, we demonstrate that laminar shear stress (LSS) significantly reduces latexin (LXN) expression in ECs. By using siRNA and cell imaging, we demonstrated that LXN knockdown results in the morphologic change and F-actin remodelling just like what LSS does in ECs. We further demonstrate that LXN interacts with Filamin A (FLNA) and regulates FLNA proteolytic cleavage and nuclei translocation. By constructing LXN-/- mice and ApoE-/- LXN-/- double knockout mice, we evaluated the effect of LXN knockout on aortic endothelium damage in mice. We found that LXN deficiency significantly improves vascular permeability, vasodilation and atherosclerosis in mice. Our findings provide confident evidence, for the first time, that LXN is a novel regulator for morphological maintenance of ECs, and LXN deficiency has a protective effect on vascular homeostasis. This provides new strategies and drug targets for the treatment of vascular diseases.
Assuntos
Citoesqueleto/metabolismo , Endotélio Vascular/metabolismo , Filaminas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Aorta/citologia , Aorta/metabolismo , Aorta/fisiologia , Apolipoproteínas E/genética , Circulação Sanguínea , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Proteólise , Estresse Mecânico , VasodilataçãoRESUMO
The role of the LMNA gene in the development and progression of hepatocellular carcinoma (HCC) and the associated molecular mechanism is not yet clear. Therefore, the purpose of this study was to evaluate the relationship between LMNA and HCC. LMNA gene expression in normal tissues and corresponding tumours was evaluated and the Kaplan-Meier survival analysis was performed. Next, the LMNA gene was knocked out in the 293T and HepG2 cell lines using the CRISPR/Cas9 technique. Subsequently, the proliferation, migration and colony formation rate of the two LMNA knockout cell lines were analysed. Finally, the molecular mechanism affecting the tumorigenesis due to the loss of the LMNA gene was evaluated. The results showed that the LMNA gene was abnormally expressed in many tumours, and the survival rate of the HCC patients with a high expression of the LMNA gene was significantly reduced compared with the rate in patients with a low LMNA expression. The knockout of the LMNA gene in the HCC cell line HepG2 resulted in a decreased tumorigenicity, up-regulation of the P16 expression and down-regulation of the CDK1 expression. These findings suggested that LMNA might function as an oncogene in HCC and provided a potential new target for the diagnosis and treatment of HCC.
Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular , Lamina Tipo A/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Oncogenes , Animais , Apoptose/genética , Sequência de Bases , Sistemas CRISPR-Cas/genética , Pontos de Checagem do Ciclo Celular/genética , Movimento Celular/genética , Proliferação de Células/genética , Matriz Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Transdução de Sinais , Ensaio Tumoral de Célula-Tronco , Regulação para Cima/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The function of Latexin (LXN) in inflammation has attracted attention. However, no data are available regarding its role in colitis. We report that LXN is a suppressor of colitis. LXN deficiency leads to the severity of colitis in DSS-induced mice, and LXN is required for the therapeutic effect of retinoic acid on colitis. Using a proteomics approach, we demonstrate that LXN interacts and forms a functional complex with HECTD1 (an E3 ubiquitin ligase) and ribosomal protein subunit3 (Rps3). IκBα is one of the substrates of HECTD1. Ectopic expression of LXN leads to IκBα accumulation in intestinal epithelial cells, however, LXN knockdown enhances the interaction of HECTD1 and Rps3, contributing to the ubiquitination degradation of IκBα, and subsequently enhances inflammatory response. Thus, our findings provided a novel mechanism underlying LXN modulates colitis via HECTD1/Rps3/NF-κB pathway and significant implications for the development of novel strategies for the treatment of colitis by targeting LXN.
Assuntos
Colite/genética , Colite/patologia , Técnicas de Inativação de Genes , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Transdução de Sinais/genética , Regulação para Cima , Sequência de Aminoácidos , Animais , Linhagem Celular , Humanos , Inflamação/genética , Inflamação/patologia , Camundongos , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Proteínas Ribossômicas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
Organic compounds that contain nitrogen are very important intermediates in pharmaceutical and chemical industry. Hydroamination is the reaction that can form C-N bond with high atom economy. The research progress in metals catalyzed hydroamination of alkenes and alkynes from the perspective of reaction mechanism is categorized and summarized.