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Liu G, Hu YG, Wu YB, Shan WY, Tang YJ. [Lutein inhibits the adhesion, invasiveness and metastasis of human prostate cancer PC-3M cells]. Zhonghua Nan Ke Xue 2023; 29:210-217. [PMID: 38597701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
OBJECTIVE To explore the effects of lutein on the adhesion, invasiveness and metastasis of human prostate cancer PC-3M cells and its action mechanism. METHODS We divided human prostate cancer PC-3M cells into a control, a low-dose lutein, a medium-dose lutein and a high-dose lutein group, and treated them with 0, 10, 20 and 40 μmol/L lutein, respectively. Then we examined the adhesion of the cells to matrix by cell adhesion assay and the changes in cell pseudopodia by Phalloidin staining, detected the expressions of paxillin, matrix metalloproteinase 2 (MMP-2), MMP-9, recombinant tissue inhibitors of metalloproteinase 1 (TIMP-1), E-cadherin, N-cadherin and vimentin by Western blot, determined the invasiveness and migration of the cells by scratch and Transwell assays, and observed their dynamic movement by high-intension imaging. RESULTS Compared with the control, the lutein intervention groups showed significant reduction in the number of the cells adhered to matrix, the number of cell pseudopodia, the expressions of paxillin, MMP-2, MMP-9, N-cadherin and vimentin, the rates of migration, invasion and metastasis, and the distances of displacement and movement of the cells. However, the expressions of TIMP-1 and epithelial-mesenchymal transition-related E-cadherin were upregulated significantly. CONCLUSION Lutein can inhibit cell adhesion, reduce the expressions of MMPs, and suppress cell invasion and migration by inhibiting the process of epithelial-mesenchymal transition.
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Affiliation(s)
- Guang Liu
- Department of Urology, Armed Police Corps Hospital of Jiangsu Province, Yangzhou, Jiangsu 225003, China
| | - You-Gen Hu
- Department of Urology, Armed Police Corps Hospital of Jiangsu Province, Yangzhou, Jiangsu 225003, China
| | - Yun-Bing Wu
- Department of Urology, Armed Police Corps Hospital of Jiangsu Province, Yangzhou, Jiangsu 225003, China
| | - Wei-Yuan Shan
- Department of Urology, Armed Police Corps Hospital of Jiangsu Province, Yangzhou, Jiangsu 225003, China
| | - Yuan-Jie Tang
- Department of Urology, Armed Police Corps Hospital of Jiangsu Province, Yangzhou, Jiangsu 225003, China
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Noto F, Recuero S, Valencia J, Saporito B, Robbe D, Bonet S, Carluccio A, Yeste M. Inhibition of Potassium Channels Affects the Ability of Pig Spermatozoa to Elicit Capacitation and Trigger the Acrosome Exocytosis Induced by Progesterone. Int J Mol Sci 2021; 22:ijms22041992. [PMID: 33671466 PMCID: PMC7922121 DOI: 10.3390/ijms22041992] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 02/16/2021] [Accepted: 02/16/2021] [Indexed: 01/02/2023] Open
Abstract
During capacitation, sperm undergo a myriad of changes, including remodeling of plasma membrane, modification of sperm motility and kinematic parameters, membrane hyperpolarization, increase in intracellular calcium levels, and tyrosine phosphorylation of certain sperm proteins. While potassium channels have been reported to be crucial for capacitation of mouse and human sperm, their role in pigs has not been investigated. With this purpose, sperm samples from 15 boars were incubated in capacitation medium for 300 min with quinine, a general blocker of potassium channels (including voltage-gated potassium channels, calcium-activated potassium channels, and tandem pore domain potassium channels), and paxilline (PAX), a specific inhibitor of calcium-activated potassium channels. In all samples, acrosome exocytosis was induced after 240 min of incubation with progesterone. Plasma membrane and acrosome integrity, membrane lipid disorder, intracellular calcium levels, mitochondrial membrane potential, and total and progressive sperm motility were evaluated after 0, 120, and 240 min of incubation, and after 5, 30, and 60 min of progesterone addition. Although blocking potassium channels with quinine and PAX prevented sperm to elicit in vitro capacitation by impairing motility and mitochondrial function, as well as reducing intracellular calcium levels, the extent of that inhibition was larger with quinine than with PAX. Therefore, while our data support that calcium-activated potassium channels are essential for sperm capacitation in pigs, they also suggest that other potassium channels, such as the voltage-gated, tandem pore domain, and mitochondrial ATP-regulated ones, are involved in that process. Thus, further research is needed to elucidate the specific functions of these channels and the mechanisms underlying its regulation during sperm capacitation.
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Affiliation(s)
- Federico Noto
- Biotechnology of Animal and Human Reproduction (TechnoSperm), Institute of Food and Agricultural Technology, University of Girona, ES-17003 Girona, Spain; (F.N.); (S.R.); (S.B.)
- Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, ES-17003 Girona, Spain;
- Faculty of Veterinary Medicine, University of Teramo, Località Piano D’Accio, IT-64100 Teramo, Italy; (B.S.); (D.R.); (A.C.)
| | - Sandra Recuero
- Biotechnology of Animal and Human Reproduction (TechnoSperm), Institute of Food and Agricultural Technology, University of Girona, ES-17003 Girona, Spain; (F.N.); (S.R.); (S.B.)
- Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, ES-17003 Girona, Spain;
| | - Julián Valencia
- Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, ES-17003 Girona, Spain;
- University Antonio Nariño, Calle 53 #9-35, Popayán CO-190002, Colombia
| | - Beatrice Saporito
- Faculty of Veterinary Medicine, University of Teramo, Località Piano D’Accio, IT-64100 Teramo, Italy; (B.S.); (D.R.); (A.C.)
| | - Domenico Robbe
- Faculty of Veterinary Medicine, University of Teramo, Località Piano D’Accio, IT-64100 Teramo, Italy; (B.S.); (D.R.); (A.C.)
| | - Sergi Bonet
- Biotechnology of Animal and Human Reproduction (TechnoSperm), Institute of Food and Agricultural Technology, University of Girona, ES-17003 Girona, Spain; (F.N.); (S.R.); (S.B.)
- Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, ES-17003 Girona, Spain;
| | - Augusto Carluccio
- Faculty of Veterinary Medicine, University of Teramo, Località Piano D’Accio, IT-64100 Teramo, Italy; (B.S.); (D.R.); (A.C.)
| | - Marc Yeste
- Biotechnology of Animal and Human Reproduction (TechnoSperm), Institute of Food and Agricultural Technology, University of Girona, ES-17003 Girona, Spain; (F.N.); (S.R.); (S.B.)
- Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, ES-17003 Girona, Spain;
- Correspondence:
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Abstract
Paxillin is extensively involved in focal adhesion signaling and kinase signaling throughout the plasma membrane and cytoplasm. However, recent studies in prostate cancer suggest that paxillin also plays a critical role in regulating gene expression within the nucleus, serving as a liaison between cytoplasmic and nuclear MAPK and Androgen Receptor (AR) signaling. Here we used RNA-seq to examine the paxillin-regulated transcriptome in several human prostate cancer cell lines. First, we examined paxillin effects on androgen-mediated transcription in control or paxillin-depleted AR-positive LNCaP and C4-2 human prostate cancer cells. In androgen-dependent LNCaP cells, we found over 1000 paxillin-dependent androgen-responsive genes, some of which are involved in endocrine therapy resistance. Most paxillin-dependent AR-mediated genes in LNCaP cells were no longer paxillin-dependent in androgen-sensitive, castration-resistant C4-2 cells, suggesting that castration-resistance may markedly alter paxillin effects on genomic AR signaling. To examine the paxillin-regulated transcriptome in the absence of androgen signaling, we performed RNA-seq in AR-negative PC3 human prostate cancer cells. Paxillin enhanced several pro-proliferative pathways, including the CyclinD/Rb/E2F and DNA replication/repair pathways. Additionally, paxillin suppressed pro-apoptotic genes, including CASP1 and TNFSF10. Quantitative PCR confirmed that these pathways are similarly regulated by paxillin in LNCaP and C4-2 cells. Functional studies showed that, while paxillin stimulated cell proliferation, it had minimum effect on apoptosis. Thus, paxillin appears to be an important transcriptional regulator in prostate cancer, and analysis of its transcriptome might lead to novel approaches toward the diagnosis and treatment of this important disease.
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Affiliation(s)
- Xiaoting Ma
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Rochester Medical School, Rochester, NY, United States
| | - Anindita Biswas
- Department of Animal Science, College of Agriculture and Natural Resources, Michigan State University, Lansing, MI, United States
| | - Stephen R Hammes
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Rochester Medical School, Rochester, NY, United States.
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Tishkin SM, Rekalov VV, Ivanova IV, MoreLand RS, Soloviev AI. Ionizing non-fatal whole-body irradiation inhibits Ca2+-dependent K+channels in endothelial cells of rat coronary artery: Possible contribution to depression of endothelium-dependent vascular relaxation. Int J Radiat Biol 2009; 83:161-9. [PMID: 17378524 DOI: 10.1080/09553000601146931] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE The goal of this study was to evaluate the influence of ionizing irradiation on large conductance Ca2+-dependent potassium (BKCa) channels in rat coronary endothelial cells. MATERIALS AND METHODS Rats were exposed to a 6 Gy dose from a cobalt60 source. Experimental design of this study comprised recording of contractile force using isolated rat aortic rings and whole-cell patch clamp techniques to study whole-cell potassium currents in isolated rat coronary artery endothelial cells. RESULTS It has been shown that outward potassium currents in endothelial cells 9 days after irradiation appear to be suppressed or even totally abolished. The reversal potential for these currents in irradiated cells was shifted to more positive values. Paxilline (500 nM), an inhibitor of BKCa channels, had no or only a negligible effect on irradiated cells. The experiments using isolated aortic rings demonstrated that both paxilline and irradiation significantly shifted the acetylcholine dependent concentration-relaxation response curve to the right. Irradiated tissues were insensitive to paxilline. CONCLUSION The results suggest that non-fatal, whole-body gamma-irradiation suppresses large conductance, calcium-activated potassium channels, which control the driving force for Ca2+ entry and therefore Ca2+ dependent nitric oxide (NO) synthesis in endothelial cells. This may contribute, in part, to radiation-induced endothelium dysfunction and an increase in arterial blood pressure.
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Affiliation(s)
- Sergey M Tishkin
- Institute of Pharmacology and Toxicology, Academy of Medical Sciences, Kiev, Ukraine
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Huang J, Liang JT, Huang HC, Shen TL, Chen HY, Lin NY, Che MI, Lin WC, Huang MC. Beta1,4-N-acetylgalactosaminyltransferase III enhances malignant phenotypes of colon cancer cells. Mol Cancer Res 2007; 5:543-52. [PMID: 17579116 DOI: 10.1158/1541-7786.mcr-06-0431] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The enzyme beta1,4-N-acetylgalactosaminyltransferase III (beta4GalNAc-T3) exhibits in vitro activity of synthesizing N,N'-diacetyllactosediamine, GalNAcbeta1,4GlcNAc. Here, we investigate the expression of beta4GalNAc-T3 in primary colon tumors and the effects of its overexpression on HCT116 colon cancer cells. Real-time reverse transcription-PCR showed that the expression of beta4GalNAc-T3 was up-regulated in 72.5% (n = 40) of primary colon tumors compared with their normal counterparts. beta4GalNAc-T3 overexpression resulted in enhanced cell-extracellular matrix adhesion, migration, anchorage-independent cell growth, and invasion of colon cancer cells. Moreover, beta4GalNAc-T3 overexpression increased tumor growth and metastasis and decreased survival of tumor-bearing nude mice. beta4GalNAc-T3 overexpression showed increased tyrosine phosphorylation of focal adhesion kinase and paxillin Y118 as well as increased extracellular signal-regulated kinase phosphorylation. These results suggest that up-regulation of beta4GalNAc-T3 may play a critical role in promoting tumor malignancy and that integrin and mitogen-activated protein kinase signaling pathways could be involved in the underlying mechanism.
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Affiliation(s)
- John Huang
- Department of Surgery, National Taiwan University Hospital, Taiwan
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Wang YJ, Sung RJ, Lin MW, Wu SN. Contribution of BKCa-Channel Activity in Human Cardiac Fibroblasts to Electrical Coupling of Cardiomyocytes-Fibroblasts. J Membr Biol 2007; 213:175-85. [PMID: 17483867 DOI: 10.1007/s00232-007-0027-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Revised: 10/16/2006] [Indexed: 01/30/2023]
Abstract
Cardiac fibroblasts are involved in the maintenance of myocardial tissue structure. However, little is known about ion currents in human cardiac fibroblasts. It has been recently reported that cardiac fibroblasts can interact electrically with cardiomyocytes through gap junctions. Ca(2+)-activated K(+) currents (I (K[Ca])) of cultured human cardiac fibroblasts were characterized in this study. In whole-cell configuration, depolarizing pulses evoked I (K(Ca)) in an outward rectification in these cells, the amplitude of which was suppressed by paxilline (1 microM: ) or iberiotoxin (200 nM: ). A large-conductance, Ca(2+)-activated K(+) (BK(Ca)) channel with single-channel conductance of 162 +/- 8 pS was also observed in human cardiac fibroblasts. Western blot analysis revealed the presence of alpha-subunit of BK(Ca) channels. The dynamic Luo-Rudy model was applied to predict cell behavior during direct electrical coupling of cardiomyocytes and cardiac fibroblasts. In the simulation, electrically coupled cardiac fibroblasts also exhibited action potential; however, they were electrically inert with no gap-junctional coupling. The simulation predicts that changes in gap junction coupling conductance can influence the configuration of cardiac action potential and cardiomyocyte excitability. I (k(Ca)) can be elicited by simulated action potential waveforms of cardiac fibroblasts when they are electrically coupled to cardiomyocytes. This study demonstrates that a BK(Ca) channel is functionally expressed in human cardiac fibroblasts. The activity of these BK(Ca) channels present in human cardiac fibroblasts may contribute to the functional activities of heart cells through transfer of electrical signals between these two cell types.
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Affiliation(s)
- Ya-Jean Wang
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, No. 1, University Road, Tainan, 701, Taiwan
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Romanenko VG, Nakamoto T, Srivastava A, Begenisich T, Melvin JE. Regulation of membrane potential and fluid secretion by Ca2+-activated K+ channels in mouse submandibular glands. J Physiol 2007; 581:801-17. [PMID: 17379640 PMCID: PMC2075181 DOI: 10.1113/jphysiol.2006.127498] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We have recently shown that the IK1 and maxi-K channels in parotid salivary gland acinar cells are encoded by the K(Ca)3.1 and K(Ca)1.1 genes, respectively, and in vivo stimulated parotid secretion is severely reduced in double-null mice. The current study tested whether submandibular acinar cell function also relies on these channels. We found that the K(+) currents in submandibular acinar cells have the biophysical and pharmacological footprints of IK1 and maxi-K channels and their molecular identities were confirmed by the loss of these currents in K(Ca)3.1- and K(Ca)1.1-null mice. Unexpectedly, the pilocarpine-stimulated in vivo fluid secretion from submandibular glands was essentially normal in double-null mice. This result and the possibility of side-effects of pilocarpine on the nervous system, led us to develop an ex vivo fluid secretion assay. Fluid secretion from the ex vivo assay was substantially (about 75%) reduced in animals with both K(+) channel genes ablated - strongly suggesting systemic complications with the in vivo assay. Additional experiments focusing on the membrane potential in isolated submandibular acinar cells revealed mechanistic details underlying fluid secretion in K(+) channel-deficient mice. The membrane potential of submandibular acinar cells from wild-type mice remained strongly hyperpolarized (-55 +/- 2 mV) relative to the Cl(-) equilibrium potential (-24 mV) during muscarinic stimulation. Similar hyperpolarizations were observed in K(Ca)3.1- and K(Ca)1.1-null mice (-51 +/- 3 and -48 +/- 3 mV, respectively), consistent with the normal fluid secretion produced ex vivo. In contrast, acinar cells from double K(Ca)3.1/K(Ca)1.1-null mice were only slightly hyperpolarized (-35 +/- 2 mV) also consistent with the ex vivo (but not in vivo) results. Finally, we found that the modest hyperpolarization of cells from the double-null mice was maintained by the electrogenic Na(+),K(+)-ATPase.
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Affiliation(s)
- Victor G Romanenko
- Center for Oral Biology in the Aab Institute of Biomedical Sciences and Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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Park SY, Li H, Avraham S. RAFTK/Pyk2 regulates EGF-induced PC12 cell spreading and movement. Cell Signal 2007; 19:289-300. [PMID: 16945503 DOI: 10.1016/j.cellsig.2006.07.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 06/29/2006] [Accepted: 07/04/2006] [Indexed: 01/13/2023]
Abstract
The protein tyrosine kinase RAFTK, also termed Pyk2, is a member of the focal adhesion kinase (FAK) subfamily. In this report, we show the role of RAFTK in neuroendocrine PC12 cells upon epidermal growth factor (EGF) stimulation. Following EGF treatment, we observed that RAFTK was tyrosine-phosphorylated in a time- and dose-dependent manner, while FAK was constitutively phosphorylated and primarily regulated by cell adhesion. Moreover, we found that RAFTK associated with the phosphorylated EGF receptor (EGFR) upon EGF stimulation. RAFTK phosphorylation was mediated primarily through PLCgamma-IP3-Ca(2+) signaling and partially through PI3-Kinase. Furthermore, overexpression of PRNK, a specific dominant-negative construct of RAFTK, was sufficient to block EGF-induced cell spreading and movement. Paxillin, a key modulator of the actin cytoskeleton and an RAFTK substrate, was also phosphorylated following EGF treatment. EGF induced a dynamic reorganization of RAFTK and paxillin at neuronal adhesion sites, with the specific localization of paxillin at the inner juxtaposition of RAFTK. Additionally, we observed that RAFTK associated with the scaffold protein c-Cbl and mediated its phosphorylation. Our data demonstrate that while FAK mediated cell adhesion, RAFTK was localized at the cytoplasm where it mediated inside-out signaling through intracellular Ca(2+), thus leading to cell spreading and movement upon EGF stimulation.
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Affiliation(s)
- Shin-Young Park
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Harvard Institutes of Medicine, 4 Blackfan Circle, Boston, MA 02215, USA
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Shin S, Paul-Satyaseela M, Maneesh PS, Lee JS, Romer LH, Kim KS. Focal adhesion kinase is involved in type III group B streptococcal invasion of human brain microvascular endothelial cells. Microb Pathog 2006; 41:168-73. [PMID: 16949788 DOI: 10.1016/j.micpath.2006.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Revised: 06/08/2006] [Accepted: 07/07/2006] [Indexed: 11/26/2022]
Abstract
Group B streptococcus (GBS), the leading cause of neonatal meningitis, has been shown to invade human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. GBS invasion of HBMEC has been shown to require the host cell actin cytoskeleton rearrangements. The present study examined the mechanisms underlying actin cytoskeleton rearrangements that are involved in type III GBS invasion of HBMEC. We showed that type III GBS invasion was inhibited by genistein, a general tyrosine kinase inhibitor (mean 54% invasion decrease at 100 microM), and LY294002, a phosphatidylinositol 3 (PI3) kinase inhibitor (mean 70% invasion decrease at 50 microM), but not by PP2, an inhibitor of the Src family tyrosine kinases. We subsequently showed that the focal adhesion kinase (FAK) was the one of the host proteins tyrosine phosphorylated by type III GBS. Over-expression of a dominant negative form of the FAK C-terminal domain significantly decreased type III GBS invasion of HBMEC (mean 51% invasion decrease). In addition, we showed that FAK phosphorylation correlated with its association of paxillin, an adapter protein of actin filament, and PI3-kinase subunit p85. This is the first demonstration that FAK phosphorylation and its association with paxillin and PI3 kinase play a key role in type III GBS invasion of HBMEC.
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Affiliation(s)
- Sooan Shin
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Park 256, Baltimore, MD 21287, USA
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Alon R, Feigelson SW, Manevich E, Rose DM, Schmitz J, Overby DR, Winter E, Grabovsky V, Shinder V, Matthews BD, Sokolovsky-Eisenberg M, Ingber DE, Benoit M, Ginsberg MH. Alpha4beta1-dependent adhesion strengthening under mechanical strain is regulated by paxillin association with the alpha4-cytoplasmic domain. ACTA ACUST UNITED AC 2006; 171:1073-84. [PMID: 16365170 PMCID: PMC2171310 DOI: 10.1083/jcb.200503155] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The capacity of integrins to mediate adhesiveness is modulated by their cytoplasmic associations. In this study, we describe a novel mechanism by which α4-integrin adhesiveness is regulated by the cytoskeletal adaptor paxillin. A mutation of the α4 tail that disrupts paxillin binding, α4(Y991A), reduced talin association to the α4β1 heterodimer, impaired integrin anchorage to the cytoskeleton, and suppressed α4β1-dependent capture and adhesion strengthening of Jurkat T cells to VCAM-1 under shear stress. The mutant retained intrinsic avidity to soluble or bead-immobilized VCAM-1, supported normal cell spreading at short-lived contacts, had normal α4-microvillar distribution, and responded to inside-out signals. This is the first demonstration that cytoskeletal anchorage of an integrin enhances the mechanical stability of its adhesive bonds under strain and, thereby, promotes its ability to mediate leukocyte adhesion under physiological shear stress conditions.
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Affiliation(s)
- Ronen Alon
- Department of Immunology, The Weizmann Institute of Science, Rehovot 76100, Israel.
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