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Pezzotta A, Brioschi L, Carbone S, Mazzoleni B, Bontempi V, Monastra F, Mauri L, Marozzi A, Mione M, Pistocchi A, Viani P. Combined Inhibition of Hedgehog and HDAC6: In Vitro and In Vivo Studies Reveal a New Role for Lysosomal Stress in Reducing Glioblastoma Cell Viability. Int J Mol Sci 2023; 24:ijms24065771. [PMID: 36982845 PMCID: PMC10051748 DOI: 10.3390/ijms24065771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 03/22/2023] Open
Abstract
Glioblastoma multiforme (GBM) is the most common and malignant brain tumor in adults. The invasiveness and the rapid progression that characterize GBM negatively impact patients’ survival. Temozolomide (TMZ) is currently considered the first-choice chemotherapeutic agent. Unfortunately, over 50% of patients with GBM do not respond to TMZ treatment, and the mutation-prone nature of GBM enables the development of resistance mechanisms. Therefore, efforts have been devoted to the dissection of aberrant pathways involved in GBM insurgence and resistance in order to identify new therapeutic targets. Among them, sphingolipid signaling, Hedgehog (Hh) pathway, and the histone deacetylase 6 (HDAC6) activity are frequently dysregulated and may represent key targets to counteract GBM progression. Given the positive correlation between Hh/HDAC6/sphingolipid metabolism in GBM, we decided to perform a dual pharmacological inhibition of Hh and HDAC6 through cyclopamine and tubastatin A, respectively, in a human GMB cell line and zebrafish embryos. The combined administration of these compounds elicited a more significant reduction of GMB cell viability than did single treatments in vitro and in cells orthotopically transplanted in the zebrafish hindbrain ventricle. We demonstrated, for the first time, that the inhibition of these pathways induces lysosomal stress which results in an impaired fusion of lysosomes with autophagosomes and a block of sphingolipid degradation in GBM cell lines. This condition, which we also recapitulated in zebrafish embryos, suggests an impairment of lysosome-dependent processes involving autophagy and sphingolipid homeostasis and might be instrumental in the reduction of GBM progression.
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Affiliation(s)
- Alex Pezzotta
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
| | - Loredana Brioschi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
| | - Sabrina Carbone
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
| | - Beatrice Mazzoleni
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
- Molecular Mechanisms Unit, Fondazione IRCCS Istituto Nazionale dei Tumori di Milano, Via Giacomo Venezian, 1, 20133 Milano, Italy
| | - Vittorio Bontempi
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Federica Monastra
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
| | - Laura Mauri
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
| | - Anna Marozzi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
| | - Marina Mione
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Anna Pistocchi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
- Correspondence: (A.P.); (P.V.)
| | - Paola Viani
- Department of Medical Biotechnology and Translational Medicine, University of Milan, L.I.T.A., Via Fratelli Cervi 93, Segrate, 20054 Milano, Italy
- Correspondence: (A.P.); (P.V.)
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Gurianov DS, Antonenko SV, Telegeev GD. Colocalization of BCR Protein with Clathrin, Actin, and Cortactin Suggests Its Possible Role in the Regulation of Actin Branching and Clathrin-Mediated Endocytosis. CYTOL GENET+ 2021. [DOI: 10.3103/s0095452721020055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Liu X, Huang J, Liu L, Liu R. MPZL1 is highly expressed in advanced gallbladder carcinoma and promotes the aggressive behavior of human gallbladder carcinoma GBC‑SD cells. Mol Med Rep 2019; 20:2725-2733. [PMID: 31322261 PMCID: PMC6691252 DOI: 10.3892/mmr.2019.10506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 05/09/2019] [Indexed: 01/17/2023] Open
Abstract
Myelin protein 0‑like 1 (MPZL1) has been reported to have a role in hepatocellular carcinoma. However, to the best of our knowledge, there have been no studies on the function and molecular mechanism of MPZL1 gene in gallbladder carcinoma. The present study confirmed that MPZL1 was upregulated in four gallbladder carcinoma tissues according to the mRNA microarray analysis. The results of the immunohistochemical analysis of tissues from 82 patients with gallbladder carcinoma demonstrated that patients with advanced tumor stages (both T and N stage) had higher positive expression of MPZL1. Moreover, a total of 20 cases of gallbladder carcinoma and matched paired paracarcinoma tissues along with 20 samples of healthy gallbladder tissue from patients with cholecystitis were analyzed using reverse transcription‑quantitative PCR and western blotting. The results demonstrated that the expression of MPZL1 in gallbladder carcinoma tissues was significantly higher than that of paired paracarcinoma tissues and randomly matched normal gallbladder epithelial tissues. According to the Tumor‑Node‑Metastasis classification, the expression level of MPZL1 protein in stage IV gallbladder carcinoma was significantly higher than that in stage III gallbladder carcinoma. The enhanced expression of MPZL1 gene appeared to improve the migration ability of GBC‑SD cells. Conversely, GBC‑SD cells that transfected with MPZL1 siRNA exhibited decreased migration ability. The results of proliferation experiments showed that the knockdown of MPZL1 siRNA caused impairments in GBC‑SD cell proliferation. On the contrary, the overexpression of MPZL1 increased the proliferation ability of GBC‑SD cells. The results of flow cytometry analyses indicated that the upregulation of MPZL1 had an anti‑apoptotic effect on GBC‑SD cells. In conclusion, the present study showed that the expression and protein levels of MPZL1 were significantly higher in gallbladder carcinoma tissues, especially in patients diagnosed with advanced tumor stages. Overexpression of MPZL1 may have promoted the invasion, metastasis, proliferation and survival of GBC‑SD cells.
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Affiliation(s)
- Xiaolei Liu
- Department of Hepato‑Pancreato‑Biliary Surgical Oncology, Chinese PLA General Hospital, Beijing 100853, P.R. China
| | - Jia Huang
- Department of General Surgery, China‑Japan Friendship Hospital, Beijing 100029, P.R. China
| | - Liguo Liu
- Department of General Surgery, China‑Japan Friendship Hospital, Beijing 100029, P.R. China
| | - Rong Liu
- Department of Hepato‑Pancreato‑Biliary Surgical Oncology, Chinese PLA General Hospital, Beijing 100853, P.R. China
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Li T, Xue Y, Wang G, Gu T, Li Y, Zhu YY, Chen L. Multi-target siRNA: Therapeutic Strategy for Hepatocellular Carcinoma. J Cancer 2016; 7:1317-27. [PMID: 27390607 PMCID: PMC4934040 DOI: 10.7150/jca.15157] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/18/2016] [Indexed: 12/23/2022] Open
Abstract
Multiple targets RNAi strategy is a preferred way to treat multigenic diseases, especially cancers. In the study, multi-target siRNAs were designed to inhibit NET-1, EMS1 and VEGF genes in hepatocellular carcinoma (HCC) cells. And multi-target siRNAs showed better silencing effects on NET-1, EMS1 and VEGF, compared with single target siRNA. Moreover, multi-target siRNA showed greater suppression effects on proliferation, migration, invasion, angiogenesis and induced apoptosis in HCC cells. The results suggested that multi-target siRNA might be a preferred strategy for cancer therapy and NET-1, EMS1 and VEGF could be effective targets for HCC treatments.
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Affiliation(s)
- Tiejun Li
- 1. Department of Pathological Anatomy, Nantong University, Nantong, China;; 2. Small RNA Technology and Application Institute, Nantong University, Nantong, China;; 3. Biomics Biotechnologies Co., Ltd., Nantong, China
| | - Yuwen Xue
- 1. Department of Pathological Anatomy, Nantong University, Nantong, China
| | - Guilan Wang
- 1. Department of Pathological Anatomy, Nantong University, Nantong, China
| | - Tingting Gu
- 1. Department of Pathological Anatomy, Nantong University, Nantong, China
| | - Yunlong Li
- 1. Department of Pathological Anatomy, Nantong University, Nantong, China
| | - York Yuanyuan Zhu
- 2. Small RNA Technology and Application Institute, Nantong University, Nantong, China;; 3. Biomics Biotechnologies Co., Ltd., Nantong, China
| | - Li Chen
- 1. Department of Pathological Anatomy, Nantong University, Nantong, China
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Jia D, Jing Y, Zhang Z, Liu L, Ding J, Zhao F, Ge C, Wang Q, Chen T, Yao M, Li J, Gu J, He X. Amplification of MPZL1/PZR promotes tumor cell migration through Src-mediated phosphorylation of cortactin in hepatocellular carcinoma. Cell Res 2013; 24:204-17. [PMID: 24296779 DOI: 10.1038/cr.2013.158] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 09/10/2013] [Accepted: 09/25/2013] [Indexed: 12/15/2022] Open
Abstract
We have previously identified 1 241 regions of somatic copy number alterations (CNAs) in hepatocellular carcinoma (HCC). In the present study, we found that a novel recurrent focal amplicon, 1q24.1-24.2, targets the MPZL1 gene in HCC. Notably, there is a positive correlation between the expression levels of MPZL1 and intrahepatic metastasis of the HCC specimens. MPZL1 can significantly enhance the migratory and metastatic potential of the HCC cells. Moreover, we found that one of the mechanisms by which MPZL1 promotes HCC cell migration is by inducing the phosphorylation and activation of the pro-metastatic protein, cortactin. Additionally, we found that Src kinase mediates the phosphorylation and activation of cortactin induced by MPZL1 overexpression. Taken together, these findings suggest that MPZL1 is a novel pro-metastatic gene targeted by a recurrent region of copy number amplification at 1q24.1-24.2 in HCC.
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Affiliation(s)
- Deshui Jia
- 1] State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China [2] Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Ying Jing
- 1] State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China [2] Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhenfeng Zhang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Li Liu
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Jie Ding
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Fangyu Zhao
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Chao Ge
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Qifeng Wang
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Taoyang Chen
- Qidong Liver Cancer Institute, Qidong, Jiangsu 226200, China
| | - Ming Yao
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Jinjun Li
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Jianren Gu
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
| | - Xianghuo He
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032, China
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Herrmann S, Ninkovic M, Kohl T, Lörinczi É, Pardo LA. Cortactin controls surface expression of the voltage-gated potassium channel K(V)10.1. J Biol Chem 2012; 287:44151-63. [PMID: 23144454 PMCID: PMC3531731 DOI: 10.1074/jbc.m112.372540] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
KV10.1 is a voltage-gated potassium channel aberrantly expressed in many cases of cancer, and participates in cancer initiation and tumor progression. Its action as an oncoprotein can be inhibited by a functional monoclonal antibody, indicating a role for channels located at the plasma membrane, accessible to the antibody. Cortactin is an actin-interacting protein implicated in cytoskeletal architecture and often amplified in several types of cancer. In this study, we describe a physical and functional interaction between cortactin and KV10.1. Binding of these two proteins occurs between the C terminus of KV10.1 and the proline-rich domain of cortactin, regions targeted by many post-translational modifications. This interaction is specific for KV10.1 and does not occur with KV10.2. Cortactin controls the abundance of KV10.1 at the plasma membrane and is required for functional expression of KV10.1 channels.
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Affiliation(s)
- Solveig Herrmann
- Oncophysiology Group, Max-Planck Institute of Experimental Medicine, Hermann-Rein-Str. 3, 37075 Göttingen, Germany
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Huang Y, Biswas C, Klos Dehring DA, Sriram U, Williamson EK, Li S, Clarke F, Gallucci S, Argon Y, Burkhardt JK. The actin regulatory protein HS1 is required for antigen uptake and presentation by dendritic cells. THE JOURNAL OF IMMUNOLOGY 2011; 187:5952-63. [PMID: 22031761 DOI: 10.4049/jimmunol.1100870] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The hematopoietic actin regulatory protein hematopoietic lineage cell-specific protein 1 (HS1) is required for cell spreading and signaling in lymphocytes, but the scope of HS1 function in Ag presentation has not been addressed. We show that dendritic cells (DCs) from HS1(-/-) mice differentiate normally and display normal LPS-induced upregulation of surface markers and cytokines. Consistent with their normal expression of MHC and costimulatory molecules, HS1(-/-) DCs present OVA peptide efficiently to CD4(+) T cells. However, presentation of OVA protein is defective. Similarly, MHC class I-dependent presentation of VSV8 peptide to CD8(+) T cells occurs normally, but cross-presentation of GRP94/VSV8 complexes is defective. Analysis of Ag uptake pathways shows that HS1 is required for receptor-mediated endocytosis, but not for phagocytosis or macropinocytosis. HS1 interacts with dynamin 2, a protein involved in scission of endocytic vesicles. However, HS1(-/-) DCs showed decreased numbers of endocytic invaginations, whereas dynamin-inhibited cells showed accumulation of these endocytic intermediates. Taken together, these studies show that HS1 promotes an early step in the endocytic pathway that is required for efficient Ag presentation of exogenous Ag by DCs.
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Affiliation(s)
- Yanping Huang
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Neumann AK, Jacobson K. A novel pseudopodial component of the dendritic cell anti-fungal response: the fungipod. PLoS Pathog 2010; 6:e1000760. [PMID: 20169183 PMCID: PMC2820528 DOI: 10.1371/journal.ppat.1000760] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 01/11/2010] [Indexed: 02/02/2023] Open
Abstract
Fungal pathologies are seen in immunocompromised and healthy humans. C-type lectins expressed on immature dendritic cells (DC) recognize fungi. We report a novel dorsal pseudopodial protrusion, the “fungipod”, formed by DC after contact with yeast cell walls. These structures have a convoluted cell-proximal end and a smooth distal end. They persist for hours, exhibit noticeable growth and total 13.7±5.6 µm long and 1.8±0.67 µm wide at the contact. Fungipods contain clathrin and an actin core surrounded by a sheath of cortactin. The actin cytoskeleton, but not microtubules, is required for fungipod integrity and growth. An apparent rearward flow (225±55 nm/second) exists from the zymosan contact site into the distal fungipod. The phagocytic receptor Dectin-1 is not required for fungipod formation, but CD206 (Mannose Receptor) is the generative receptor for these protrusions. The human pathogen Candida parapsilosis induces DC fungipod formation strongly, but the response is species specific since the related fungal pathogens Candida tropicalis and Candida albicans induce very few and no fungipods, respectively. Our findings show that fungipods are dynamic actin-driven cellular structures involved in fungal recognition by DC. They may promote yeast particle phagocytosis by DC and are a specific response to large (i.e., 5 µm) particulate ligands. Our work also highlights the importance of this novel protrusive structure to innate immune recognition of medically significant Candida yeasts in a species specific fashion. Yeasts are normal microbial commensals of humans and a significant source of opportunistic infections, especially in immunocompromised individuals. We report a novel cellular protrusive structure, the fungipod, which participates in the host-microbe interaction between human immature dendritic cells (DC) and yeasts. The fungipod's structure is based on and propelled by a robust process of local actin cytoskeleton growth at the DC-yeast contact site, and this cytoskeletal remodeling results in a durable tubular structure over 10 µm long connecting the dorsal DC membrane and yeast. The fungal cell wall polysaccharides mannan and chitin trigger fungipod formation by stimulating the carbohydrate pattern recognition receptor CD206. Fungipods are part of a specific response to large particulate objects (i.e., yeast), and they may promote the human immature DC's relatively poor phagocytosis of yeast. The human fungal pathogen, Candida parapsilosis, induces a strong fungipod response from DC, and this response is highly species specific since the related pathogens Candida albicans and Candida tropicalis induce fungipods rarely. Our work highlights a novel cell biological element of fungal recognition by the innate immune system.
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Affiliation(s)
- Aaron K. Neumann
- Department of Cell & Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Ken Jacobson
- Department of Cell & Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Zhang K, Wang D, Song J. Cortactin is involved in transforming growth factor-beta1-induced epithelial-mesenchymal transition in AML-12 cells. Acta Biochim Biophys Sin (Shanghai) 2009; 41:839-45. [PMID: 19779649 DOI: 10.1093/abbs/gmp070] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Cortactin is an F-actin binding protein, regulating cell movement and adhesive junction assembly. However, the function of cortactin in epithelial-mesenchymal transition (EMT) remains elusive. Here we found that during transforming growth factor-beta1 (TGF-beta1)- induced EMT in AML-12 murine hepatocytes, cortactin underwent tyrosine dephosphorylation. Inhibition of the dephosphorylation of cortactin by sodium vanadate blocked TGF-beta1-induced EMT. Knockdown of cortactin by RNAi led to decrease of intercellular junction proteins E-cadherin and Zonula occludens-1 and induced expression of mesenchymal protein fibronectin. Additionally, knockdown of cortactin further promoted TGF-beta1-induced EMT in AML-12 cells, as determined by EMT markers and cell morphological changes. Moreover, migration assay showed that cortactin knockdown promoted the migration of AML-12 cells, and also enhanced TGF-beta1-induced migration. Our study showed the involvement of cortactin in the TGFbeta1- induced EMT.
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Affiliation(s)
- Kehua Zhang
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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Connors EC, Ballif BA, Morielli AD. Homeostatic regulation of Kv1.2 potassium channel trafficking by cyclic AMP. J Biol Chem 2007; 283:3445-3453. [PMID: 18003609 DOI: 10.1074/jbc.m708875200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Shaker family potassium channel, Kv1.2, is a key determinant of membrane excitability in neurons and cardiovascular tissue. Kv1.2 is subject to multiple forms of regulation and therefore integrates cellular signals involved in the homeostasis of excitability. The cyclic AMP/protein kinase A (PKA) pathway enhances Kv1.2 ionic current; however, the mechanisms for this are not fully known. Here we show that cAMP maintains Kv1.2 homeostasis through opposing effects on channel trafficking. We found that Kv1.2 is regulated by two distinct cAMP pathways, one PKA-dependent and the other PKA-independent. PKA inhibitors elevate Kv1.2 surface levels, suggesting that basal levels of cAMP control steady-state turnover of the channel. Elevation of cAMP above basal levels also increases the amount of Kv1.2 at the cell surface. This effect is not blocked by PKA inhibitors, but is blocked by inhibition of Kv1.2 endocytosis. We conclude that Kv1.2 levels at the cell surface are kept in dynamic balance by opposing effects of cAMP.
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Affiliation(s)
- Emilee C Connors
- Department of Pharmacology, College of Medicine, University of Vermont, Burlington, Vermont 05405
| | - Bryan A Ballif
- Department of Biology, University of Vermont, Burlington, Vermont 05405
| | - Anthony D Morielli
- Department of Pharmacology, College of Medicine, University of Vermont, Burlington, Vermont 05405.
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Abstract
Cortactin, an actin filament-binding protein and target of multiple kinases, has emerged as a central element connecting signaling pathways with cytoskeleton restructuring. It is involved in a perplexingly diverse array of cellular processes, including cell motility, invasiveness, synaptogenesis, endocytosis, intercellular contact assembly, and host-pathogen interactions, where the common denominator appears to be a role in the coordination of membrane dynamics with cytoskeletal remodeling. Although in recent years our knowledge about cortactin has increased exponentially, the exact mechanisms underlying its fundamental roles remain to be defined.
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Affiliation(s)
- Laura I Cosen-Binker
- Saint Michael's Hospital Research Institute, Department of Surgery, University of Toronto, Ontario, Canada
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