scholarly journals A Common Variant of ASAP1 Is Associated with Tuberculosis Susceptibility in the Han Chinese Population

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Cheng Chen ◽  
Qi Zhao ◽  
Yan Shao ◽  
Yan Li ◽  
Honghuan Song ◽  
...  
Keyword(s):  
Genetic Variant ◽  
Peripheral Blood Monocyte ◽  
Gtpase Activating Protein ◽  
Potential Biomarker ◽  
Significant Locus ◽  
Latent Tb ◽  
Hydrolysis Of ◽  
Adp Ribosylation Factor ◽  
Rna Fold

Background. ASAP1 (also known as AMAP1 or DDEF1) encodes an Arf GTPase-activating protein (Arf GAP), a multifunctional scaffold protein that induces hydrolysis of GTP bound to the ADP-ribosylation factor (Arf) family GTP-binding proteins. Reduction of ASAP1 expression in vitro was related to suppression of cell migration and invasiveness. The genetic variant rs4733781 of the ASAP1 gene was revealed as a significant locus for tuberculosis (TB) susceptibility, but the results still need to be validated. Methods. Blood samples from a total of 1914 active TB and healthy controls (HC) were collected to evaluate rs4733781 and the risk of TB. Meanwhile, a total of 48 noninfected HC, latent TB-infected (LTBI) controls, and active TB were collected to assay ASAP1 expression difference among the three groups. The QuantiFERON-TB Gold In-Tube was adopted to identify noninfected HC and LTBI. Results. The genetic variant of rs4733781 was found to be significantly associated with TB, and the A allele of rs4733781 (C>A) was 0.38 and 0.43 among TB cases and HC, respectively (P=0.0035). Meanwhile, the peripheral blood monocyte RNA fold changes for the ASAP1 gene among the 16 HC, 16 LTBI, and 16 active TB were 1.088±0.4919, 2.237±0.6505, and 10.12±10.98 (F=9.559, P=0.0003), respectively, and the expression of ASAP1 was increased by 2.06-fold (P<0.0001) and 9.30-fold (P<0.0052) for LTBI and active TB, when compared to the HC. Conclusions. Our data indicated that the A allele of rs4733781 for the ASAP1 gene was in association with a decreased risk of TB. But not only that, the overexpression of the ASAP1 gene among LTBI and TB was related to the progression of TB, which further implies that the expression of ASAP1 would be a potential biomarker for LTBI and TB diagnoses.

scholarly journals Role for Gcs1p in Regulation of Arl1p atTrans-Golgi Compartments

2005 ◽  
Vol 16 (9) ◽  
pp. 4024-4033 ◽  
Author(s):  
Ya-Wen Liu ◽  
Chun-Fang Huang ◽  
Kai-Bin Huang ◽  
Fang-Jen S. Lee
Keyword(s):  
Dynamic Equilibrium ◽  
Vesicular Trafficking ◽  
Dependent Manner ◽  
Wild Type ◽  
Gtpase Activating Protein ◽  
Critical Components ◽  
Mutant Cells ◽  
Hydrolysis Of ◽  
Adp Ribosylation Factor

ADP-ribosylation factor (ARF) and ARF-like (ARL) proteins are members of the ARF family, which are critical components of several different vesicular trafficking pathways. ARFs have little or no detectable GTPase activity without the assistance of a GTPase-activating protein (GAP). Here, we demonstrate that yeast Gcs1p exhibits GAP activity toward Arl1p and Arf1p in vitro, and Arl1p can interact with Gcs1p in a GTP-dependent manner. Arl1p was observed both on trans-Golgi and in cytosol and was recruited from cytosol to membranes in a GTP-dependent manner. In gcs1 mutant cells, the fraction of Arl1p in cytosol relative to trans-Golgi was less than it was in wild-type cells. Increasing Gcs1p levels returned the distribution toward that of wild-type cells. Both Arl1p and Gcs1p influenced the distribution of Imh1p, an Arl1p effector. Our data are consistent with the conclusion that Arl1p moves in a dynamic equilibrium between trans-Golgi and cytosol, and the release of Arl1p from membranes in cells requires the hydrolysis of bound GTP, which is accelerated by Gcs1p.

scholarly journals ASAP1, a Phospholipid-Dependent Arf GTPase-Activating Protein That Associates with and Is Phosphorylated by Src

1998 ◽  
Vol 18 (12) ◽  
pp. 7038-7051 ◽  
Author(s):  
Megan T. Brown ◽  
Josefa Andrade ◽  
Harish Radhakrishna ◽  
Julie G. Donaldson ◽  
Jonathan A. Cooper ◽  
...  
Keyword(s):  
Zinc Finger ◽  
Membrane Trafficking ◽  
Tyrosine Kinases ◽  
Sh3 Domain ◽  
Ph Domain ◽  
Gtpase Activating Protein ◽  
Binding Motifs ◽  
Hydrolysis Of ◽  
Adp Ribosylation Factor

ABSTRACT Membrane trafficking is regulated in part by small GTP-binding proteins of the ADP-ribosylation factor (Arf) family. Arf function depends on the controlled exchange and hydrolysis of GTP. We have purified and cloned two variants of a 130-kDa phosphatidylinositol 4,5-biphosphate (PIP2)-dependent Arf1 GTPase-activating protein (GAP), which we call ASAP1a and ASAP1b. Both contain a pleckstrin homology (PH) domain, a zinc finger similar to that found in another Arf GAP, three ankyrin (ANK) repeats, a proline-rich region with alternative splicing and SH3 binding motifs, eight repeats of the sequence E/DLPPKP, and an SH3 domain. Together, the PH, zinc finger, and ANK repeat regions possess PIP2-dependent GAP activity on Arf1 and Arf5, less activity on Arf6, and no detectable activity on Arl2 in vitro. The cDNA for ASAP1 was independently identified in a screen for proteins that interact with the SH3 domain of the tyrosine kinase Src. ASAP1 associates in vitro with the SH3 domains of Src family members and with the Crk adapter protein. ASAP1 coprecipitates with Src from cell lysates and is phosphorylated on tyrosine residues in cells expressing activated Src. Both coimmunoprecipitation and tyrosine phosphorylation depend on the same proline-rich class II Src SH3 binding site required for in vitro association. By directly interacting with both Arfs and tyrosine kinases involved in regulating cell growth and cytoskeletal organization, ASAP1 could coordinate membrane remodeling events with these processes.

scholarly journals Adp Ribosylation Factor-like Protein 2 (Arl2) Regulates the Interaction of Tubulin-Folding Cofactor D with Native Tubulin

2000 ◽  
Vol 149 (5) ◽  
pp. 1087-1096 ◽  
Author(s):  
Arunashree Bhamidipati ◽  
Sally A. Lewis ◽  
Nicholas J. Cowan
Keyword(s):  
Cultured Cells ◽  
Gtpase Activating Protein ◽  
Adp Ribosylation ◽  
Chaperone Protein ◽  
Ras Family ◽  
Mutant Forms ◽  
Adp Ribosylation Factor ◽  
Β Tubulin

The ADP ribosylation factor-like proteins (Arls) are a family of small monomeric G proteins of unknown function. Here, we show that Arl2 interacts with the tubulin-specific chaperone protein known as cofactor D. Cofactors C, D, and E assemble the α/β- tubulin heterodimer and also interact with native tubulin, stimulating it to hydrolyze GTP and thus acting together as a β-tubulin GTPase activating protein (GAP). We find that Arl2 downregulates the tubulin GAP activity of C, D, and E, and inhibits the binding of D to native tubulin in vitro. We also find that overexpression of cofactors D or E in cultured cells results in the destruction of the tubulin heterodimer and of microtubules. Arl2 specifically prevents destruction of tubulin and microtubules by cofactor D, but not by cofactor E. We generated mutant forms of Arl2 based on the known properties of classical Ras-family mutations. Experiments using these altered forms of Arl2 in vitro and in vivo demonstrate that it is GDP-bound Arl2 that interacts with cofactor D, thereby averting tubulin and microtubule destruction. These data establish a role for Arl2 in modulating the interaction of tubulin-folding cofactors with native tubulin in vivo.

scholarly journals Role of Coatomer and Phospholipids in GTPase-activating Protein-dependent Hydrolysis of GTP by ADP-ribosylation Factor-1

2000 ◽  
Vol 275 (31) ◽  
pp. 23615-23619 ◽  
Author(s):  
Edith Szafer ◽  
Elah Pick ◽  
Miriam Rotman ◽  
Sagie Zuck ◽  
Irit Huber ◽  
...  
Keyword(s):  
Gtpase Activating Protein ◽  
Adp Ribosylation ◽  
Hydrolysis Of ◽  
Adp Ribosylation Factor

scholarly journals A New Paxillin-binding Protein, PAG3/Papα/KIAA0400, Bearing an ADP-Ribosylation Factor GTPase-activating Protein Activity, Is Involved in Paxillin Recruitment to Focal Adhesions and Cell Migration

2000 ◽  
Vol 11 (4) ◽  
pp. 1315-1327 ◽  
Author(s):  
Akiko Kondo ◽  
Shigeru Hashimoto ◽  
Hajime Yano ◽  
Kuniaki Nagayama ◽  
Yuichi Mazaki ◽  
...  
Keyword(s):  
Subcellular Localization ◽  
Binding Protein ◽  
Focal Adhesions ◽  
Cell Periphery ◽  
Gtpase Activating Protein ◽  
Protein Activity ◽  
Adp Ribosylation ◽  
Focal Contacts ◽  
Adp Ribosylation Factor

Paxillin acts as an adaptor molecule in integrin signaling. Paxillin is localized to focal contacts but seems to also exist in a relatively large cytoplasmic pool. Here, we report the identification of a new paxillin-binding protein, PAG3 (paxillin-associated protein with ADP-ribosylation factor [ARF] GTPase-activating protein [GAP] activity, number 3), which is involved in regulation of the subcellular localization of paxillin. PAG3 bound to all paxillin isoforms and was induced during monocyte maturation, at which time paxillin expression is also increased and integrins are activated. PAG3 was diffusely distributed in the cytoplasm in premature monocytes but became localized at cell periphery in mature monocytes, a fraction of which then colocalized with paxillin. PAG3, on the other hand, did not accumulate at focal adhesion plaques, suggesting that PAG3 is not an integrin assembly protein. PAG3 was identical to KIAA0400/Papα, which was previously identified as a Pyk2-binding protein bearing a GAP activity toward several ARFs in vitro. Mammalian ARFs fall into three classes, and we showed that all classes could affect subcellular localization of paxillin. We also examined possible interaction of PAG3 with ARFs and showed evidence that at least one of them, ARF6, seems to be an intracellular substrate for GAP activity of PAG3. Moreover, overexpression of PAG3, but not its GAP-inactive mutant, inhibited paxillin recruitment to focal contacts and hampered cell migratory activities, whereas cell adhesion activities were almost unaffected. Therefore, our results demonstrate that paxillin recruitment to focal adhesions is not mediated by simple cytoplasmic diffusion; rather, PAG3 appears to be involved in this process, possibly through its GAP activity toward ARF proteins. Our result thus delineates a new aspect of regulation of cell migratory activities.

scholarly journals Identification of centaurin-α1 as a potential in vivo phosphatidylinositol 3,4,5-trisphosphate-binding protein that is functionally homologous to the yeast ADP-ribosylation factor (ARF) GTPase-activating protein, Gcs1

1999 ◽  
Vol 340 (2) ◽  
pp. 359-363 ◽  
Author(s):  
Kanamarlapudi VENKATESWARLU ◽  
Paru B. OATEY ◽  
Jeremy M. TAVARÉ ◽  
Trevor R. JACKSON ◽  
Peter J. CULLEN
Keyword(s):  
Plasma Membrane ◽  
Growth Factor ◽  
Fluorescent Protein ◽  
Binding Protein ◽  
Dominant Negative ◽  
Gtpase Activating Protein ◽  
Adp Ribosylation ◽  
Adp Ribosylation Factor

Centaurin-α is a 46 kDa in vitro binding protein for the lipid second messenger PtdIns(3,4,5)P3. In this report we have addressed whether centaurin-α1, a human homologue of centaurin-α, binds PtdIns(3,4,5)P3in vivo and furthermore, identified a potential physiological function for centaurin-α1. Using confocal microscopy of live PC12 cells, transiently transfected with a chimera of green fluorescent protein (GFP) fused to the N-terminus of centaurin-α1 (GFP-centaurin-α1), we demonstrated the rapid plasma membrane recruitment of cytosolic GFP-centaurin-α1 following stimulation with either nerve growth factor or epidermal growth factor. This recruitment was dependent on the centaurin-α1 pleckstrin homology domains and was blocked by the PtdIns(4,5)P2 3-kinase (PI 3-kinase) inhibitors wortmannin (100 nM) and LY294002 (50 μM), and also by co-expression with a dominant negative p85. Functionally, we demonstrated that centaurin-α1 could complement a yeast strain deficient in the ADP-ribosylation factor (ARF) GTPase-activating protein Gcs1; a complementation that was blocked by mutagenesis of conserved cysteine residues within the ARF GTPase-activating protein analogous domain of centaurin-α1. Taken together, our data demonstrated that centaurin-α1 could potentially function as an ARF GTPase-activating protein that, on agonist stimulation, was recruited to the plasma membrane possibly through an ability to interact with PtdIns(3,4,5)P3.

Overexpression of p62 Induces Autophagy and Promotes Proliferation, Migration and Invasion of Nasopharyngeal Carcinoma Cells through Promoting ERK Signaling Pathway

2020 ◽  
Vol 20 (8) ◽  
pp. 624-637 ◽  
Author(s):  
Qiong Wu ◽  
Manlin Xiang ◽  
Kun Wang ◽  
Zhen Chen ◽  
Lu Long ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Clinical Analysis ◽  
Carcinoma Cells ◽  
Immunofluorescent Staining ◽  
Clinicopathological Parameters ◽  
Migration And Invasion ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal ◽  
Potential Biomarker

Background: Increasing evidence has shown that p62 plays an important role in tumorigenesis. However, relatively little is known about the association between p62 and tumor invasion and metastasis; in addition, its role in NPC (nasopharyngeal carcinoma, NPC) has been rarely investigated. Objective: To investigate the effect of p62 on tumorigenesis and metastasis in nasopharyngeal carcinoma. Methods: Western blotting, immunofluorescent staining and immunohistochemistry were used to evaluate p62 protein expression. Subsequently, cell viability, colony formation, migration, invasion and autophagy assays were performed. anti-p62 autoantibodies in sera were detected by ELISA. These data were correlated with clinicopathological parameters. Results: We confirmed that p62 was significantly up-regulated in NPC tissues. Furthermore, high expression of p62 was observed in NPC cell lines, and especially in the highly metastatic 5-8F cells. In vitro, down-regulation of p62 inhibited proliferation, clone forming ability, autophagy, migration, and invasion in 5-8F cells, whereas p62 overexpression resulted in the opposite effects in 6-10B cells. Moreover, we confirmed that p62 promotes NPC cell proliferation, migration, and invasion by activating ERK (extracellular signal-regulated kinase, ERK). Clinical analysis indicated that high p62 expression correlates with lymph node and distant metastasis (P<0.05). Serum anti-p62 autoantibodies were increased in NPC patients and levels were associated with metastasis. Conclusion : Our data establish p62 targeting ERK as potential determinant in the NPC, which supplies a new pathway to treat NPC. Furthermore, p62 is a potential biomarker which might be closely related to the tumorigenesis and metastasis in NPC.

Total Synthesis and Antibacterial Screening of (±)-6,8-Dihydroxy-3- undecyl-3,4-dihydroisochromen-1-one: A Structural Analogue of Metabolites from Ononis natrix

2019 ◽  
Vol 16 (3) ◽  
pp. 245-248
Author(s):  
Hummera Rafique ◽  
Aamer Saeed ◽  
Ehsan Ullah Mughal ◽  
Muhammad Naveed Zafar ◽  
Amara Mumtaz ◽  
...  
Keyword(s):  
Total Synthesis ◽  
Structural Analog ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Antibacterial Screening ◽  
Maximum Inhibition ◽  
Bacillus Subtilus ◽  
Hydrolysis Of ◽  
Direct Condensation

Background: (±)-6,8-Dihydroxy-3-undecyl-3,4-dihydroisochromen-1-one is one of the structural analog of several substituted undecylisocoumarins isolated from Ononis natrix (Fabaceae), has been successfully synthesized by direct condensation of homopthalic acid (1) with undecanoyl chloride yields isochromen-1-one (2). Methods: Alkaline hydrolysis of (2) gave the corresponding keto-acid (3), which is then reduced to hydroxy acid (4) then its cyclodehydration was carried out with acetic anhydride to afford 3,4- dihydroisochromen-1-one (5). Followed by demethylation step, the synthesis of target 6,8- dihydroxy-7-methyl-3-undecyl-3,4-dihydroisocoumarin (6) was achieved. Results: In vitro antibacterial screening of all the synthesized compounds were carried out against ten bacterial strains by agar well diffusion method. Conclusion: Newly synthesized molecules exhibited moderate antibacterial activity and maximum inhibition was observed against Bacillus subtilus and Salmonella paratyphi.

Studies on the mechanism of acute inhibition of thyroglobulin hydrolysis by iodine

1985 ◽  
Vol 108 (4) ◽  
pp. 511-517 ◽  
Author(s):  
Nandalal Bagchi ◽  
Birdie Shivers ◽  
Thomas R. Brown
Keyword(s):  
Time Course ◽  
Period 2 ◽  
Iodotyrosine Deiodinase ◽  
Rate Of Hydrolysis ◽  
Underlying Mechanisms ◽  
Excess Iodide ◽  
Sites Of Action ◽  
Hydrolysis Of

Abstract. Iodine in excess is known to acutely inhibit thyroidal secretion. In the present study we have characterized the time course of the iodine effect in vitro and investigated the underlying mechanisms. Labelled thyroid glands were cultured in vitro in medium containing mononitrotyrosine, an inhibitor of iodotyrosine deiodinase. The rate of hydrolysis of labelled thyroglobulin was measured as the proportion of labelled iodotyrosines and iodothyronines recovered at the end of culture and was used as an index of thyroidal secretion. Thyrotrophin (TSH) administered in vivo acutely stimulated the rate of thyroglobulin hydrolysis. Addition of Nal to the culture medium acutely inhibited both basal and TSH-stimulated thyroglobulin hydrolysis. The effect of iodide was demonstrable after 2 h, maximal after 6 h and was not reversible upon removal of iodide. Iodide abolished the dibutyryl cAMP induced stimulation of thyroglobulin hydrolysis. Iodide required organic binding of iodine for its effect but new protein or RNA synthesis was not necessary. The inhibitory effects of iodide and lysosomotrophic agents such as NH4C1 and chloroquin on thyroglobulin hydrolysis were additive suggesting different sites of action. Iodide added in vitro altered the distribution of label in prelabelled thyroglobulin in a way that suggested increased coupling in the thyroglobulin molecule. These data indicate that 1) the iodide effect occurs progressively over a 6 h period, 2) continued presence of iodide is not necessary once the inhibition is established, 3) iodide exerts its action primarily at a post cAMP, prelysosomal site and 4) the effect requires organic binding of iodine, but not new RNA or protein synthesis. Our data are consistent with the hypothesis that excess iodide acutely inhibits thyroglobulin hydrolysis by increasing the resistance of thyroglobulin to proteolytic degradation through increased iodination and coupling.

scholarly journals Hsa_circ_0005273 facilitates breast cancer tumorigenesis by regulating YAP1-hippo signaling pathway

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Xuehui Wang ◽  
Changle Ji ◽  
Jiashu Hu ◽  
Xiaochong Deng ◽  
Wenfang Zheng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Signaling Pathway ◽  
Cell Lines ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Hippo Signaling ◽  
Hippo Signaling Pathway ◽  
Potential Biomarker

Abstract Background Circular RNAs (circRNAs), a novel class of endogenous RNAs, have shown to participate in the development of breast cancer (BC). Hsa_circ_0005273 is a circRNA generated from several exons of PTK2. However, the potential functional role of hsa_circ_0005273 in BC remains largely unknown. Here we aim to evaluate the role of hsa_circ_0005273 in BC. Methods The expression level of hsa_circ_0005273 and miR-200a-3p were examined by RT-qPCR in BC tissues and cell lines. The effect of knocking down hsa_circ_0005273 in BC cell lines were evaluated by examinations of cell proliferation, migration and cell cycle. In addition, xenografts experiment in nude mice were performed to evaluate the effect of hsa_circ_0005273 in BC. RNA immunoprecipitation assay, RNA probe pull-down assay, luciferase reporter assay and fluorescence in situ hybridization were conducted to confirm the relationship between hsa_circ_0005273, miR-200a-3p and YAP1. Results Hsa_circ_0005273 is over-expressed in BC tissues and cell lines, whereas miR-200a-3p expression is repressed. Depletion of hsa_circ_0005273 inhibited the progression of BC cells in vitro and in vivo, while overexpression of hsa_circ_0005273 exhibited the opposite effect. Importantly, hsa_circ_0005273 upregulated YAP1 expression and inactivated Hippo pathway via sponging miR-200a-3p to promote BC progression. Conclusions Hsa_circ_0005273 regulates the miR-200a-3p/YAP1 axis and inactivates Hippo signaling pathway to promote BC progression, which may become a potential biomarker and therapeutic target.

Sign in / Sign up

Export Citation Format

Share Document