关键词： ACTIVATING TRANSCRIPTION   THERAPEUTIC TARGET   POTENTIAL IMMUNE   DOWN-REGULATION   UP-REGULATION   EXPRESSION   CONTRIBUTES   FIBROSIS   CELLS   GENE  

摘要： Endothelial to mesenchymal transition (EndMT) is an important pathological change in many diseases. Semaphorin7A (Sema7A) has been reported to regulate nerve and vessel homeostasis, but its role in EndMT remains unclear. Here we investigate the effect of Sema7A on EndMT and the underlying mechanism. Sema7A-overexpressed human umbilical vein endothelial cells (Sema7A-HUVECs) were generated and showed lower levels of endothelial cell markers and higher levels of mesenchymal cell markers indicating the occurrence of EndMT. RNA-sequencing analysis showed a total of 1168 upregulated genes and 886 downregulated genes. Among them, most of the molecules associated with EndMT were upregulated in Sema7A-HUVECs. Mechanistically, Sema7A-HUVECs showed a higher TGF-beta 2 expression and activated TGF-beta/Smad Signaling. Importantly, Sema7A overexpression upregulated activating transcription factor 3 (ATF3) that was found to selectively bind the promotor region of TGF-beta 2, but not TGF-beta 1, promoting TGF-beta 2 transcription, which was further confirmed by ATF3-siRNA knockdown approach. Blocking beta 1 integrin, a known Sema7A receptor, alleviated the expression of ATF3, TGF-beta 2, and EndMT in Sema7A-overexpressed HUVECs, implying a role of beta 1 integrin/ATF3/TGF-beta 2 axis in mediating Sema7A-induced EndMT. Using Sema7A-deficient mice and the partial carotid artery ligation (PCL) model, we showed that Sema7A deletion attenuated EndMT induced by blood flow disturbance in vivo. In conclusion, Sema7A promotes TGF-beta 2 secretion by upregulating transcription factor ATF3 in a beta 1 integrin-dependent manner, and thus facilitates EndMT through TGF/Smad signaling, implying Sema7A as a potential therapeutic target for EndMT-related vascular diseases.

关键词： END RULE PATHWAY   UBIQUITIN-PROTEASOME SYSTEM   N-TERMINAL ARGINYLATION   PROTEIN-PROTEIN INTERACTIONS   STRESS-INDUCIBLE GENE   STRUCTURAL BASIS   SPLIT-UBIQUITIN   QUALITY-CONTROL   MICE LACKING   CELLULAR-PROTEINS  

摘要： The Arg/N-degron pathway targets proteins for degradation by recognizing their specific N-terminal residues or, alternatively, their non-N-terminal degrons. In mammals, this pathway is mediated by the UBR1, UBR2, UBR4, and UBR5 E3 ubiquitin ligases, and by the p62 regulator of autophagy. UBR1 and UBR2 are sequelogous, functionally overlapping, and dominate the targeting of Arg/N-degron substrates in examined cell lines. We constructed, here, mouse strains in which the double mutant [UBR1(-/-)UBR2(-/-)] genotype can be induced conditionally, in adult mice. We also constructed human [UBR1(-/-)UBR2(-/-)] HEK293T cell lines that unconditionally lack UBR1/UBR2. ATF3 is a basic leucine zipper transcription factor that regulates hundreds of genes and can act as either a repressor or an activator of transcription. Using the above double-mutant mice and human cells, we found that the levels of endogenous, untagged ATF3 were significantly higher in both of these [UBR1(-/-)UBR2(-/-)] settings than in wild-type cells. We also show, through chase-degradation assays with [UBR1(-/-)UBR2(-/-)] and wild-type human cells, that the Arg/N-degron pathway mediates a large fraction of ATF3 degradation. Furthermore, we used split-ubiquitin and another protein interaction assay to detect the binding of ATF3 to both UBR1 and UBR2, in agreement with the UBR1/UBR2-mediated degradation of endogenous ATF3. Full-length 24 kDa ATF3 binds to similar to 100 kDa fragments of 200 kDa UBR1 and UBR2 but does not bind (in the setting of interaction assays) to full-length UBR1/UBR2. These and other binding patterns, whose mechanics remain to be understood, may signify a conditional (regulated) degradation of ATF3 by the Arg/N-degron pathway.

关键词： ACTIVATING TRANSCRIPTION FACTOR-3   NEUROPATHIC PAIN   KNEE OSTEOARTHRITIS   GENE-EXPRESSION   NEURONS   MODEL   NERVE   ATF3   SENSITIZATION   CONTRIBUTES  

摘要： Objective. To investigate the relationship between pain behavior and potassium voltage-gated channel subfamily A member 2 (KCNA2) expression in dorsal root ganglia (DRGs) of rats with osteoarthritis (OA).Methods. Male Sprague-Dawley rats were randomly divided into three groups: blank control group (group C), normal saline group (group S), and group OA. Paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) were measured one day before injection and one, two, four, and six weeks after injection. At one, two, four, and six weeks after injection, pathological knee joint changes and activated transcription factor-3 (ATF-3) and KCNA2 expressions in DRGs were ***. Compared with preinjection, PWMT and PWTL at two, four, and six weeks after injection were significantly decreased in the group OA (P<0.05or 0.01). Compared with group C, PWMT and PWTL at two, four, and six weeks after injection were significantly decreased in the group OA (P<0.05or 0.01). In the group OA, slight local articular cartilage surface destruction was found at week one. The cartilage surface destruction gradually developed, and the exacerbation of cartilage matrix reduction and bone hyperplasia were increasingly aggravated and eventually evolved into advanced OA in the second to sixth weeks. Compared with group C, ATF-3 expression was significantly increased, and KCNA2 expression was significantly decreased in the group OA at two, four, and six weeks after injection (P<0.05or 0.01). Compared to baseline, ATF-3 expression was significantly increased, and KCNA2 expression was significantly decreased in the group OA (P<0.05or 0.01).Conclusion. Pain behavior in OA rats was associated with decreased KCNA2 expression in DRGs.

关键词： activating transcription factor 3   Crohn's disease   inflammatory bowel disease   ulcerative colitis  

摘要： Introduction: Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the intestinal tract. Known types are Crohn's disease (CD) and ulcerative colitis (UC), but their cause remains unclear and there is no convenient biomarker for IBD. The present study aimed to demonstrate an association between the onset of CD and activating transcription factor 3 (ATF3); as a new biomarker, measurement of blood ATF3 mRNA would be useful for distinguishing between CD and UC. Methods: First, in a mouse model of IBD in which damage to the intestinal mucosa was chemically induced with dextran sulfate sodium (DSS), intestinal ATF3 mRNA was evaluated. Next, in human subjects, CD and UC patients, blood ATF3 mRNA and intestinal ATF3 protein production were evaluated. Results: In the mouse model of IBD, intestinal ATF3 mRNA was elevated compared with the control (P < 0.0001). In CD patients, blood ATF3 mRNA was elevated as compared with normal controls (NCs) and UC patients (P < 0.05). In addition, we observed an increase in ATF3 production in the intestinal tract specific to CD. Conclusion: ATF3 is involved in the onset of CD, and blood ATF3 mRNA measurements would be useful for distinguishing it from UC. [ABSTRACT FROM AUTHOR]

关键词： 转录激活因子3   乳腺肿瘤   生物信息学  

摘要： 目的 分析活化转录因子3(ATF3)在乳腺癌中的表达情况及作用.方法 查询癌症和肿瘤基因表达图谱\基因表达汇编(TCGA\GEO)数据库信息,应用生物信息学方法分析ATF3在乳腺癌中的表达水平,绘制生存曲线,构建ATF3基因互作网络并行功能和通路富集分析.结果 乳腺癌中ATF3mRNA水平明显低于正常乳腺组织,经过化疗后其ATF3表达水平显著升高.生存分析发现经过系统治疗后,ATF3高表达组的乳腺癌患者,其生存期明显延长,差异有统计学意义(P<0.05).富集分析发现与乳腺癌相关的通路富集在Estrogen信号通路、丝裂原活化蛋白激酶(MAPK)信号通路、磷脂酰肌醇3-激酶-蛋白激酶B(PI3K-Akt)信号通路、Wnt信号通路、Breast cancer信号通路、cell cycle信号通路.结论 ATF3参与调控乳腺癌细胞的增殖,系统治疗后,ATF3的高表达预示着更好的预后.

关键词： 转录激活因子3   乳腺丝氨酸蛋白酶抑制因子   基质金属蛋白酶2   脑膜瘤  

摘要： 目的探讨转录激活因子3(ATF3)、乳腺丝氨酸蛋白酶抑制因子(maspin)和基质金属蛋白酶2(MMP2)在人脑各病理分级脑膜瘤中的表达和临床意义。方法采用免疫组化染色法、qRT-PCR和Western blot法检测71例脑膜瘤和32例正常脑组织中ATF3、maspin和MMP2的蛋白和mRNA表达情况,分析其在不同病理级别脑膜瘤患者中的可能作用和临床意义。结果 ATF3和MMP2在脑膜瘤中的表达明显高于正常脑组织,maspin在脑膜瘤中的表达明显低于正常脑组织。随着脑膜瘤病理级别的增高,ATF3和MMP2的表达量逐级增高,而maspin表达量逐级递减。ATF3和MMP2的蛋白和mRNA表达与脑膜瘤病理分级呈正相关,maspin蛋白和mRNA表达与脑膜瘤病理分级呈负相关。结论 ATF3、maspin和MMP2可能协同参与了脑膜瘤发生,ATF3、maspin和MMP2可能与脑膜瘤恶性进展紧密相关。

关键词： adipose-derived stem cells   critical gap   differentiation   peripheral nerve   regeneration   tubulization   ENGINEERED NEURAL TISSUE   TRANSPLANTATION   REPAIR   ATF3   GUIDES   INJURY   DEFECT   MOTOR   RATS  

摘要： Introduction Many reports have indicated that adipose-derived stem cells (ADSCs) are effective for nerve regeneration. We investigated nerve regeneration by combining a polyglycolic acid collagen (PGA-c) tube, which is approved for clinical use, and Schwann cell-like differentiated ADSCs (dADSCs). Methods Fifteen-millimeter-long gaps in the sciatic nerve of rats were bridged in each group using tubes (group I), with tubes injected with dADSCs (group II), or by resected nerve (group III). Results Axonal outgrowth was greater in group II than in group I. Tibialis anterior muscle weight revealed recovery only in group III. Latency in nerve conduction studies was equivalent in group II and III, but action potential was lower in group II. Transplanted dADSCs maintained Schwann cell marker expression. ATF3 expression level in the dorsal root ganglia was equivalent in groups II and III. Discussion dADSCs maintained their differentiated state in the tubes and are believed to have contributed to nerve regeneration.

关键词： DORSAL-ROOT GANGLIA   NERVE-FIBER DENSITY   SENSORY NEURONS   PERIPHERAL NEUROPATHY   DAMAGE   MODEL   ATF3   REGENERATION   COMBINATION   PATHOLOGY  

摘要： HIV-associated sensory neuropathy is a common neurologic comorbidity of HIV infection and prevails in the post-antiretroviral therapy (ART) era. HIV infection drives pathologic changes in the dorsal root ganglia (DRG) through inflammation, altered metabolism, and neuronal dysfunction. Herein, we characterized specific neuronal populations in an SIV-infected macaque model with or without ART. DRG neuronal populations were identified by neurofilament H-chain 200, I-B-4 isolectin (IB4), or tropomyosin receptor kinase A expression and assessed for cell body diameter, population size, apoptotic markers, and regeneration signaling. IB4(+) and tropomyosin receptor kinase A-positive neurons showed a reduced cell body size (atrophy) and decreased population size (cell death) in the DRG of SIV-infected animals compared with uninfected animals. IB4(+) nonpeptidergic neurons were less affected in the presence of ART. DRG neurons showed accumulation of cleaved caspase 3 (apoptosis) and nuclear-localized activating transcription factor 3 (regeneration) in SIV infection, which was significantly lower in uninfected animals and SIV-infected animals receiving ART. Nonpeptidergic neurons predominantly colocalized with cleaved caspase 3 staining. Nonpeptidergic and peptidergic neurons colocalized with nuclear-accumulated activating transcription factor 3, showing active regeneration in sensory neurons. These data suggest that nonpeptidergic and peptidergic neurons are susceptible to pathologic changes from SIV infection, and intervention with ART did not fully ameliorate damage to the DRG, specifically to peptidergic neurons.

关键词： ATF3   bta-miR-1271   preadipocyte differentiation   Yanbian yellow cattle   ADIPOCYTE DIFFERENTIATION   ADIPOGENIC DIFFERENTIATION   ADIPOSE-TISSUE   STEM-CELLS   ATF3   EXPRESSION   MIR-1271   GROWTH   CANCER   PROLIFERATION  

摘要： Yanbian yellow cattle are one of the top five largest breeds of cattle in China. We had previously found that bta-miR-1271 is differentially expressed in the longissimus dorsi muscles of Yanbian yellow bulls and steers. However, whether bta-miR-1271 affects bovine fat formation is unclear. In this study, we used target gene prediction, dual-luciferase reporter assay, and transfection-mediated overexpression and inhibition of bta-miR-1271 in a culture of Yanbian yellow cattle preadipocytes to investigate the role of bta-miR-1271 in adipogenesis. We showed that bta-miR-1271 directly targets the 3 '-untranslated region (3 '-UTR) of the activating transcription factor 3 (ATF3) mRNA and downregulates its expression. Overexpression of bta-miR-1271 enforced by the miRNA mimics promoted triglyceride accumulation and significantly upregulated expression of the adipogenic peroxisome proliferator-activated receptor gamma (PPAR gamma) and CCAAT enhancer-binding protein alpha (C/EBP alpha) genes at both the protein and mRNA levels, as demonstrated by RT-qPCR and Western blot analyses. Conversely, inhibition of bta-miR-1271 expression produced the opposite effect. Our results show that bta-miR-1271 regulates differentiation of Yanbian yellow cattle preadipocytes by inhibitingATF3expression, which highlights the importance of microRNA-mediated regulation of adipogenesis. miR-1271 and its target gene(s) may provide a new research direction for investigating biological agents affecting intramuscular fat deposition in cattle.

关键词： CHOP   DDIT1   ER stress   GAD45A   NOXA   PUMA   RCAN1   RNA-seq   UPR   ENDOPLASMIC-RETICULUM STRESS   UNFOLDED-PROTEIN-RESPONSE   ACTIVATING TRANSCRIPTION FACTOR-3   DEATH RECEPTOR 5   CFTR EXPRESSION   UP-REGULATION   CELL-DEATH   ATF3   WEB   COORDINATION  

摘要： Endoplasmic reticulum (ER) stress conditions promote a cellular adaptive mechanism called the unfolded protein response (UPR) that utilizes three stress sensors, inositol-requiring protein 1, protein kinase RNA-like ER kinase, and activating transcription factor 6. These sensors activate a number of pathways to reduce the stress and facilitate cell survival. While much is known about the mechanisms involved that modulate apoptosis during chronic stress, less is known about the transition between the prosurvival and proapoptotic factors that determine cell fate. Here, we employed a genetic screen that utilized three different pharmacological stressors to induce ER stress in a human-immortalized airway epithelial cell line, immortalized human bronchial epithelial cells. We followed the stress responses over an 18-h time course and utilized real-time monitoring of cell survival, next-generation sequencing, and quantitative real-time PCR to identify and validate genes that were upregulated with all three commonly employed ER stressors, inhibitor of calpain 1, tunicamycin, and thapsigargin. growth arrest and DNA damage-inducible alpha (GADD45A), a proapoptotic factor, and regulator of calcineurin 1 (RCAN1) mRNAs were identified and verified by showing that small interfering RNA (siRNA) knockdown of GADD45A decreased CCAAT-enhancer-binding protein homologous protein (a.k.a DDIT3), BCL2-binding component 3 (a.k.a. BBC3), and phorbol-12-myristate-13-acetate-induced protein 1 expression, 3 proapoptotic factors, and increased cell viability during ER stress conditions, whereas siRNA knockdown of RCAN1 dramatically decreased cell viability. These results suggest that the relative levels of these two genes regulate cell fate decisions during ER stress independent of the type of ER stressor.