关键词： Bone marrow-derived macrophage   Cell migration   IQ motif containing GTPase activating protein 1   Liver inflammation and fibrosis   Sphingosine 1-phosphate  

摘要： IQ motif containing GTPase activating protein 1 (IQGAP1), a scaffold protein, is implicated in cell migration. Our previous studies demonstrate that sphingosine 1-phosphate (S1P) induces bone marrow-derived macrophages (BMDMs) recruitment and promotes chronic liver inflammation/fibrosis. However, the role of IQGAP1 in S1P-induced BMDM migration and liver inflammation/fibrosis remains unclear. Mouse liver fibrosis was induced by carbon tetrachloride (CCl), bile duct ligation (BDL) or methionine-choline-deficient and high-fat (MCDHF) diet. Immunofluorescence and single-cell RNA sequencing were employed to study the expression of IQGAP1 in fibrotic liver. Selective knockdown of IQGAP1 expression in macrophages was performed using IQGAP1 siRNA-GeRPs. RT-qPCR and western blot were used to assess gene expression. The Boyden chamber assay was employed to analyze BMDM migration in vitro. IQGAP1, with significantly elevated expression, was highly expressed by hepatic macrophages and positively related with inflammatory marker expression in human or mouse fibrotic livers. In vivo, selective knockdown of IQGAP1 in macrophages effectively alleviated mouse liver inflammation/fibrosis. In vitro, IQGAP1, which was increased in S1P-treated BMDMs, participated in S1P-induced BMDM migration. S1P up-regulated IQGAP1 expression in a S1P receptor 2/3 (S1PR) dependent manner. S1P/S1PR regulated IQGAP1 expression via up-regulating RNA binding protein Hu antigen R (HuR) expression. Further studies demonstrated that miR-455-5p, which was down-regulated by S1P, was also involved in IQGAP1 expression and BMDM migration. In conclusion, IQGAP1 plays a crucial role in S1P-induced BMDM migration and liver inflammation/fibrosis, providing new insight into the contribution of IQGAP1 to chronic liver inflammation/fibrosis.

关键词： N-WASP   IQGAP1   细胞骨架   微丝   微管   海鞘  

摘要： 细胞骨架由肌动蛋白丝(微丝)、微管和中间丝构成,是细胞的主要支持结构。细胞骨架在细胞迁移、形变、增殖、极性建立等多种细胞行为中发挥着至关重要的作用。其中,微丝和微管系统的调控并非孤立,而是通过多种途径协同作用的。近年来,细胞骨架的协作机制逐渐成为骨架动态调控研究中的热点,大量细胞骨架调节蛋白被发现参与骨架协作。N-WASP蛋白参与微丝成核和分枝产生。IQGAP1蛋白具有微丝和微管的交联能力,具有同时调控微丝微管骨架系统动态的功能,且N-WASP和IQGAP1可以形成复合体发挥功能。该文综述了N-WASP和IQGAP1在细胞骨架调控中的功能,以及二者对细胞行为和组织器官形态发生的调控机制,提出了N-WASPIQGAP1复合体是一个潜在的细胞骨架协同调控单元,而海鞘脊索细胞可作为探究该复合体调控骨架协作机制的理想模型。

关键词： Bladder cancer   Cytoskeleton reorganization   TNF-alpha   METTL3   CLASP2   IQGAP1  

摘要： Background: Bladder cancer (BCa) metastasis is a multi-step process triggered by cytoskeleton reorganization. However, the regulation mechanism of cytoskeleton reorganization in BCa remains ambiguous. This study elucidated the influence of tumor necrosis factor-alpha (TNF-alpha) in cytoskeleton remodeling during BCa metastasis and its possible mechanisms. Methods: Colony formation, scratch, transwell, and the nude mouse model were adopted to evaluate the growth and metastasis. Molecular expression was assessed by immunohistochemical staining, quantitative real-time PCR (qRT-PCR), and Western blotting. The N6-methyladenosine (m6A) level was detected by methylated RNA immunoprecipitation (MeRIP). Protein interaction was validated by Co-immunoprecipitation (Co-IP). Immunofluorescence staining was used to identify rearrangement of actin filament fibers (F-actin) and protein colocalization. Results: TNF-alpha facilitated cytoplasmic linker associated protein 2 (CLASP2) and methyltransferase like 3 (METTL3) expression in a dose (10-50 ng/mL)-dependent manner in BCa. CLASP2 high expression suggested a shorter overall survival of BCa patients. CLASP2 deficiency suppressed BCa cell proliferation, migration, and invasion via disrupting F-actin cytoskeleton. Mechanistically, TNF-alpha promoted METTL3-mediated m6A modification of CLASP2 to enhance CLASP2 mRNA stability. Moreover, CLASP2 directly interplayed with IQ motif containing GTPase activating protein 1 (IQGAP1) to regulate F-actin cytoskeleton remodeling. In vivo data demonstrated that inhibition of METTL3/CLASP2 axis delayed lung metastasis in nude mice. Conclusion: TNF-alpha favors BCa cell metastasis, which involves METTL3-mediated m6A modification of CLASP2 that interacts with IQGAP1, thus leading to F-actin cytoskeleton remodeling. Our findings suggest targeting TNF alpha/METTL3/CLASP2/IQGAP1 axis as a potential avenue for promising treatment for BCa.

关键词： Enterovirus A71   IQGAP1   Exosome   lipid-biosynthesis  

摘要： This study employed a multi-omics integration approach to identify circulating biomarkers for gastric cancer (GC). We analyzed plasma and tumor tissue single-cell RNA sequencing data, along with gene and protein quantitative trait loci analyses. Leveraging data from UK Biobank and FinnGen, we investigated genetic associations with GC. Through colocalization, Mendelian Randomization, and various filtering analyses, we identified four genes (IQGAP1, KRTCAP2, PARP1, MLF2) and four proteins (EGFL9 [DLK2], ECM1, PDIA5, TIMP4) as potential GC biomarkers. These were selected based on significant genetic colocation probabilities and significant associations with GC. Seven of these biomarkers demonstrated predictive capability for GC occurrence, with AUC ranging from 0.61 to 0.99. Drug prediction analysis identified seven protein biomarkers as potential targets for immunotherapy, targeted therapies, and tumor chemotherapy. Further scRNA-seq analysis revealed significant expression differences between gastric tumor and normal tissues, particularly the upregulation of IQGAP1, which highlights its role in tumor growth.

关键词： Hippo pathway   IQGAP1   malignant melanoma   Pannexin 1   YAP  

摘要： In this study, we explored the intricate relationship between Pannexin 1 (PANX1) and the Hippo signaling pathway effector, Yes-associated protein (YAP). Analysis of The Cancer Genome Atlas (TCGA) data revealed a significant positive correlation between PANX1 mRNA and core Hippo components, Yes-associated protein 1 [YAP], Transcriptional coactivator with PDZ-binding motif [TAZ], and Hippo scaffold, Ras GTPase-activating-like protein IQGAP1 [IQGAP1], in invasive cutaneous melanoma and breast carcinoma. Furthermore, we demonstrated that PANX1 expression is upregulated in invasive melanoma cell lines and is associated with increased YAP protein levels. Notably, our investigations uncovered a previously unrecognized interaction between endogenous PANX1 and the Hippo scaffold protein IQGAP1 in melanoma cells. Moreover, our findings revealed that IQGAP1 exhibits differential expression in melanoma cells and plays a regulatory role in cellular morphology. Functional studies involving PANX1 knockdown provided compelling evidence that PANX1 modulates YAP protein levels and its cotranscriptional activity in melanoma and breast carcinoma cells. Importantly, our study highlights the potential therapeutic significance of targeting PANX1. Pharmacological inhibition of PANX1 using selective FDA-approved inhibitors or PANX1 knockdown reduced YAP levels in melanoma cells. Furthermore, our Clariom (TM) S analysis unveiled key genes implicated in cell proliferation, such as neuroglin1 (NRG1), beta-galactoside binding protein and galectin-3 (LGALS3), that are affected in PANX1-deficient cells. In summary, our investigation delves into the intricate interplay between PANX1 and YAP in the context of invasive melanoma, offering valuable insights into potential therapeutic strategies for effective treatment.

关键词： CDC42   IQGAP1   Phagocytosis   Apostichopus japonicus   Innate immunity   Invertebrate   Aquaculture health  

摘要： Cell Division Cycle 42 protein (CDC42) is a pivotal member of the Rho family of small GTPases, integral to cell signaling and the regulation of cell polarity. CDC42 is extensively documented to participate in host immunity, particularly in processes such as phagocytosis and cell migration. Nevertheless, the precise mechanisms by which CDC42 affects host-bacteria interactions remain unclear in Echinoderms. In this study, we have isolated and characterized the CDC42 gene from Apostichopus japonicus, referred to as AjCDC42. The complete cDNA sequence of AjCDC42 extends 1282 base pairs, including a typical classical RHO domain, spanning amino acids from 6 to 179. Spatial expression analysis demonstrated that AjCDC42 is ubiquitously expressed across all examined tissues. Following infection with Vibrio splendidus and stimulation with LPS, the protein and mRNA levels of AjCDC42 were significantly upregulated in coelomocytes. Moreover, the knockdown of AjCDC42 significantly decreased V. splendidus-induced phagocytic activity in coelomocytes, leading to a reduced intracellular load of V. splendidus, as evidenced by flow cytometry and bacterial plate counting assays. Mechanistically, AjCDC42 was identified as an interacting partner of IQ Motif Containing GTPase Activating Protein 1 (AjIQGAP1) through the use of co-immunoprecipitation, immunofluorescence, and GST pull-down assays combined with mass spectrometry techniques. Additional functional analyses revealed that the knockdown of AjIQGAP1 similarly decreased the phagocytic activity and the intracellular load of V. splendidus in coelomocytes. Furthermore, we detected that decreased levels of AjCDC42 and AjIQGAP1 impaired cytoskeletal rearrangement and delayed lysosomal clearance of V. splendidus. In summary, our findings underscore the pivotal role of the AjCDC42AjIQGAP1 axis in regulating coelomocytes phagocytosis in A. japonicus during V. splendidus infection.

关键词： IQGAP1   neutrophils   CD11c   integrin  

摘要： IQ motif containing GTPase activating protein 1 (IQGAP1) is a protein scaffold that integrates signals regulating various cellular functions. Recently, utilizing proteomics as a discovery tool and co-immunoprecipitation as a validation method, we reported IQGAP1 as a potential ligand for CD11c, an adhesion molecule that was highly expressed in the intracellular components of neutrophils and regulated the maturation, survival, and function of neutrophils. To date, the role of IQGAP1 in inflammation and immune response is largely unknown. In this study, we reported the direct binding of CD11c with IQGAP1 through various methods. In addition, we investigated the role of IQGAP1 in neutrophil functions by using IQGAP1 knockout (KO) mice. We discovered that IQGAP1 deficiency led to impaired bone marrow neutrophil maturation, reactive oxygen species (ROS) generation, phagocytosis, and neutrophil extracellular traps formation. Thus, for the first time, we reported the essential role of IQGAP1 in neutrophil development.

关键词： Ischemic stroke   Platelet-related genes   IQGAP1   Diagnostic marker   Immune cells  

摘要： Introduction: Ischemic stroke (IS) is a complex illness resulting from a combination of numerous environmental and genetic risk factors. Recent reports have shed light on the vital role that platelets play in the pathophysiology of IS. Here, we aimed to explore the potential platelet-related genes in IS and investigate the effect of plateletrelated genes in the immune microenvironment of IS. Methods: The data of IS were retrieved from the Gene Expression Omnibus database. Firstly, we screened the platelet-related genes that were correlated with the onset of IS using differential expression analysis, enrichment analyses, and protein-protein interaction (PPI) network. Moreover, we analyzed the clinical value and functional information of platelet-related genes in IS. Finally, we explored the correlation between platelet-related genes and immune cells' infiltration. Results: Ten platelet-related genes that were correlated with the onset of IS were identified, among which IQGAP1 was located at the core of the PPI network. IQGAP1 was found to be expressed in the normal brain tissue and its expression was significantly elevated in IS samples. The area under the curve (AUC) values for IQGAP1 in both the GSE16561 and GSE58294 datasets were close to 1. IQGAP1 knockdown might increase OGD/R-induced HT22 cell viability. Additionally, FoxO signaling pathway, NOD-like receptor signaling pathway, Phagosome and Platelet activation pathways were significantly activated in IS patients with high IQGAP1 expression compared to those with low IQGAP1 expression. The IS patients in the IQGAP1high and IQGAP1low groups showed dramatically different proportions of immune cells and immune-related functions, and the IQGAP1 expression was correlated with the immune cell' infiltration in IS. Conclusions: In this study, we identified the IQGAP1 might serve as a potential diagnostic marker for IS, and the IQGAP1 expression was very relevant in determining the immune cell' infiltration in IS patien

关键词： BCSC-1   IQGAP1   细胞迁移   浸润性导管癌  

摘要： 该研究旨在探讨BCSC-1与IQGAP1对乳腺癌细胞迁移的影响及其在乳腺浸润性导管癌中的临床意义。免疫沉淀实验检测乳腺癌细胞MCF-7中BCSC-1与IQGAP1是否存在相互作用;细胞免疫荧光实验检测MCF-7细胞中BCSC-1与IQGAP1的共定位情况; Western blot检测BCSC-1、IQGAP1分别过表达对对方表达水平的影响;细胞划痕实验、细胞免疫荧光实验结合RNA干扰检测BCSC-1与IQGAP1在迁移的MCF-7、MDA-MB-231细胞中的定位情况及二者在细胞膜前缘定位的相互依赖性; Western blot检测各种乳腺癌细胞中BCSC-1与IQGAP1的蛋白表达情况;免疫组织化学染色法检测BCSC-1与IQGAP1在乳腺浸润性导管癌与癌旁组织中的表达情况及与乳腺浸润性导管癌临床病理特征关系的相关性。在MCF-7细胞中BCSC-1与IQGAP1存在相互作用及共定位; BCSC-1、IQGAP1的分别过表达并不影响彼此的表达水平;无论MCF-7和MDA-MB-231是处于随机迁移状态,还是处于定向迁移状态, BCSC-1都定位在乳腺癌细胞胞质以及膜前缘,与IQGAP1存在着共定位分布,且二者对将彼此募集到膜前缘具有相互依赖性;在多种乳腺癌细胞中,BCSC-1呈低表达而IQGAP1呈高表达;与癌旁组织相比,在浸润性导管癌组织中, BCSC-1的表达下调(P<0.05), IQGAP1的表达上调(P<0.05);在浸润性导管癌组织中, BCSC-1的表达水平与乳腺癌的组织学级别、淋巴结转移有关(P<0.05),与ER、PR和HER2的状态无关(P>0.05),而IQGAP1的高表达水平与淋巴结转移有关(P<0.05),与HER2的状态有关(P<0.05); BCSC-1和IQGAP1的表达呈负相关(R=–0.416, P<0.05)。BCSC-1和IQGAP1存在相互作用,协同调控乳腺癌细胞迁移,二者参与了乳腺浸润性导管癌的发展,并与其转移性相关。