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Kang K, Liao X, Li Q, Chen J, Niu Y, Zeng Y, Xia S, Zeng L, Liu S, Gou D. A novel tonicity-responsive microRNA miR-23a-5p modulates renal cell survival under osmotic stress through targeting heat shock protein 70 HSPA1B. Am J Physiol Cell Physiol 2020; 320:C225-C239. [PMID: 33206547 DOI: 10.1152/ajpcell.00441.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
There is growing evidence that microRNAs (miRNAs) are implicated in cellular adaptation to osmotic stress, but the underlying osmosignaling pathways are still not completely understood. In this study, we found that a passenger strand miRNA, miR-23a-5p, was significantly downregulated in response to high NaCl treatment in mouse inner medullary collecting duct cells (mIMCD3) through an miRNA profiling assay. The decrease of miR-23a-5p is hypertonicity-dependent and osmotolerant cell type-specific. Knockdown of miR-23a-5p increased cellular survival and proliferation in mIMCD3. In contrast, miR-23a-5p overexpression repressed cell viability and proliferation under hypertonic stress. RNA deep-sequencing revealed that a heat shock protein 70 (HSP70) isoform, HSP70 member 1B (HSPA1B), was significantly increased under hypertonic treatment. Based on the prediction analysis by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and TargetScan, and a further validation via a dual-luciferase assay, HSPA1B was identified as a potential target of miR-23a-5p. Overexpressed miR-23a-5p suppressed HSPA1B, whereas downregulated miR-23a-5p promoted HSPA1B expression in mIMCD3. In addition, an in vivo study demonstrated that there is a reverse correlation between the levels of miR-23a-5p and HSPA1B in mouse renal inner medulla (papilla) that is exposed to extremely high osmolality. In summary, this study elucidates that passenger strand miR-23a-5p is a novel tonicity-responsive miRNA. The downregulation of miR-23a-5p facilitates cellular adaptation to hypertonic stress in mammalian renal cells through modulating HSPA1B.
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Affiliation(s)
- Kang Kang
- Department of Biochemistry and Molecular Biology, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, Carson International Cancer Center, Shenzhen University Health Sciences Center, Shenzhen, People's Republic of China
| | - Xiaoyun Liao
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Qing Li
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Jidong Chen
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Yanqin Niu
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Yan Zeng
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Sijian Xia
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Le Zeng
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Shide Liu
- Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
| | - Deming Gou
- Department of Biochemistry and Molecular Biology, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, Carson International Cancer Center, Shenzhen University Health Sciences Center, Shenzhen, People's Republic of China.,Shenzhen Key Laboratory of Microbial Genetic Engineering, Vascular Disease Research Center, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, People's Republic of China
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2
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Epidermal Growth Factor Stimulates Fatty Acid Synthesis Mainly via PLC-γ1/Akt Signaling Pathway in Dairy Goat Mammary Epithelial Cells. Animals (Basel) 2020; 10:ani10060930. [PMID: 32481546 PMCID: PMC7341511 DOI: 10.3390/ani10060930] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/19/2020] [Accepted: 05/21/2020] [Indexed: 11/20/2022] Open
Abstract
Simple Summary Goat milk contains an abundance of fatty acids which are benefit to human health. Epidermal growth factor (EGF) is a small peptide which could positively regulate the growth, development and differentiation of the mammary gland during lactation. However, little information is available about EGF in regulating lipid metabolism in the mammary gland. This study investigated the effects of EGF on the triglyceride (TG) synthesis, lipogenic genes expression and the downstream signal protein levels in goat mammary epithelial cells (GMECs). Our findings indicated EGF might be beneficial to improve milk fat synthesis of dairy goats. Abstract EGF acts as a ligand of the EGF receptor (EGFR) to activate the EGFR-mediated signaling pathways and is involved in the regulation of cell physiology. However, the roles of EGFR mediated signaling pathways in the regulation of lipid metabolism in goat mammary epithelial cells (GMECs) are poorly understood. To evaluate the impact of EGF on GMECs, the triglyceride (TG) content and lipid droplet were detected, using TG assay and immunofluorescence. Further, expression of lipogenic genes, the protein kinase B (Akt), phospholipase C-γ1 (PLC-γ1) and extracellular signal-regulated kinases (ERK)1/2 signaling pathways were measured by real-time polymerase chain reaction and Western blot, respectively. The results showed that the mRNA expression of EGFR gene was significantly upregulated in lactating goat mammary gland tissues compared to non-lactation period (p < 0.05). TG contents in EGF-treated GMECs were significantly increased (p < 0.05), and an increase of lipid droplets was also detected. In vitro studies demonstrated that the mRNA levels of lipogenesis-related FASN, ACC, SCD1, LXRa, LXRb and SP1 genes were positively correlated to the mRNA level of EGFR gene shown by gene overexpression and silencing (p < 0.05). The phosphorylations of Akt, ERK1/2 and PLC-γ1 in GMECs were greatly upregulated in the presence of EGF, and specific inhibitors were capable of blocking the phosphorylation of Akt, ERK1/2 and PLC-γ1. Compared with EGF-treated GMECs, the mRNA levels of FASN, ACC and SCD1 were significantly decreased in GMECs co-treated with PLC-γ1 and Akt inhibitor and EGF (p < 0.05), and TG content was also dropped significantly. These observations implied that EGFR plays an important role in regulating de novo fatty acid synthesis in GMECs, mainly mediated by Akt and PLC-γ1 signaling pathways.
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Greaney AM, Adams TS, Brickman Raredon MS, Gubbins E, Schupp JC, Engler AJ, Ghaedi M, Yuan Y, Kaminski N, Niklason LE. Platform Effects on Regeneration by Pulmonary Basal Cells as Evaluated by Single-Cell RNA Sequencing. Cell Rep 2020; 30:4250-4265.e6. [PMID: 32209482 PMCID: PMC7175071 DOI: 10.1016/j.celrep.2020.03.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/24/2019] [Accepted: 03/02/2020] [Indexed: 12/16/2022] Open
Abstract
Cell-based therapies have shown promise for treating myriad chronic pulmonary diseases through direct application of epithelial progenitors or by way of engineered tissue grafts or whole organs. To elucidate environmental effects on epithelial regenerative outcomes in vitro, here, we isolate and culture a population of pharmacologically expanded basal cells (peBCs) from rat tracheas. At peak basal marker expression, we simultaneously split peBCs into four in vitro platforms: organoid, air-liquid interface (ALI), engineered trachea, and engineered lung. Following differentiation, these samples are evaluated using single-cell RNA sequencing (scRNA-seq) and computational pipelines are developed to compare samples both globally and at the population level. A sample of native rat tracheal epithelium is also evaluated by scRNA-seq as a control for engineered epithelium. Overall, this work identifies platform-specific effects that support the use of engineered models to achieve the most physiologic differential outcomes in pulmonary epithelial regenerative applications.
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Affiliation(s)
- Allison M Greaney
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA.
| | - Taylor S Adams
- Section of Pulmonary, Critical Care, and Sleep Medicine, Yale School of Medicine, New Haven, CT 06519, USA
| | - Micha Sam Brickman Raredon
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Medical Scientist Training Program, Yale University, New Haven, CT 06511, USA
| | - Elise Gubbins
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA
| | - Jonas C Schupp
- Section of Pulmonary, Critical Care, and Sleep Medicine, Yale School of Medicine, New Haven, CT 06519, USA
| | - Alexander J Engler
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA
| | - Mahboobe Ghaedi
- Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Department of Anesthesiology, Yale University, New Haven, CT 06510, USA
| | - Yifan Yuan
- Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Department of Anesthesiology, Yale University, New Haven, CT 06510, USA
| | - Naftali Kaminski
- Section of Pulmonary, Critical Care, and Sleep Medicine, Yale School of Medicine, New Haven, CT 06519, USA
| | - Laura E Niklason
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Department of Anesthesiology, Yale University, New Haven, CT 06510, USA
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4
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Kang K, Huang L, Li Q, Liao X, Dang Q, Yang Y, Luo J, Zeng Y, Li L, Gou D. An improved Tet-on system in microRNA overexpression and CRISPR/Cas9-mediated gene editing. J Anim Sci Biotechnol 2019; 10:43. [PMID: 31198556 PMCID: PMC6556963 DOI: 10.1186/s40104-019-0354-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/12/2019] [Indexed: 11/10/2022] Open
Abstract
Background Tetracycline (Tet)-regulated expression system has become a widely applied tool to control gene activity. This study aimed to improve the Tet-on system with superior regulatory characteristics. Results By comprehensively comparing factors of transactivators, Tet-responsive elements (TREs), orientations of induced expression cassette, and promoters controlling the transactivator, we developed an optimal Tet-on system with enhanced inducible efficiency and lower leakiness. With the system, we successfully performed effective inducible and reversible expression of microRNA, and presented a more precise and easily reproducible fine-tuning for confirming the target of a miRNA. Finally, the system was applied in CRISPR/Cas9-mediated knockout of nuclear factor of activated T cells-5 (NFAT5), a protective transcription factor in cellular osmoregulation. Conclusions This study established an improved Tet-on system for powerful and stringent gene regulation in functional genetic studies. Electronic supplementary material The online version of this article (10.1186/s40104-019-0354-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kang Kang
- 1Department of Biochemistry and Molecular Biology, Carson International Cancer Center, Shenzhen University Health Sciences Center, Shenzhen, Guangdong 518060 People's Republic of China
| | - Lian Huang
- 2Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100 People's Republic of China
| | - Qing Li
- 3Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Xueyuan Ave 1066, Shenzhen, Guangdong 518060 People's Republic of China
| | - Xiaoyun Liao
- 3Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Xueyuan Ave 1066, Shenzhen, Guangdong 518060 People's Republic of China
| | - Quanjin Dang
- 3Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Xueyuan Ave 1066, Shenzhen, Guangdong 518060 People's Republic of China
| | - Yi Yang
- 1Department of Biochemistry and Molecular Biology, Carson International Cancer Center, Shenzhen University Health Sciences Center, Shenzhen, Guangdong 518060 People's Republic of China
| | - Jun Luo
- 2Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100 People's Republic of China
| | - Yan Zeng
- 3Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Xueyuan Ave 1066, Shenzhen, Guangdong 518060 People's Republic of China
| | - Li Li
- 3Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Xueyuan Ave 1066, Shenzhen, Guangdong 518060 People's Republic of China
| | - Deming Gou
- 1Department of Biochemistry and Molecular Biology, Carson International Cancer Center, Shenzhen University Health Sciences Center, Shenzhen, Guangdong 518060 People's Republic of China.,3Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Xueyuan Ave 1066, Shenzhen, Guangdong 518060 People's Republic of China
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5
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CHML promotes liver cancer metastasis by facilitating Rab14 recycle. Nat Commun 2019; 10:2510. [PMID: 31175290 PMCID: PMC6555802 DOI: 10.1038/s41467-019-10364-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 04/30/2019] [Indexed: 01/08/2023] Open
Abstract
Metastasis-associated recurrence is the major cause of poor prognosis in hepatocellular carcinoma (HCC), however, the underlying mechanisms remain largely elusive. In this study, we report that expression of choroideremia-like (CHML) is increased in HCC, associated with poor survival, early recurrence and more satellite nodules in HCC patients. CHML promotes migration, invasion and metastasis of HCC cells, in a Rab14-dependent manner. Mechanism study reveals that CHML facilitates constant recycling of Rab14 by escorting Rab14 to the membrane. Furthermore, we identify several metastasis regulators as cargoes carried by Rab14-positive vesicles, including Mucin13 and CD44, which may contribute to metastasis-promoting effects of CHML. Altogether, our data establish CHML as a potential promoter of HCC metastasis, and the CHML-Rab14 axis may be a promising therapeutic target for HCC.
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6
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Winkelmann VE, Thompson KE, Neuland K, Jaramillo AM, Fois G, Schmidt H, Wittekindt OH, Han W, Tuvim MJ, Dickey BF, Dietl P, Frick M. Inflammation-induced upregulation of P2X 4 expression augments mucin secretion in airway epithelia. Am J Physiol Lung Cell Mol Physiol 2018; 316:L58-L70. [PMID: 30358443 DOI: 10.1152/ajplung.00157.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mucus clearance provides an essential innate defense mechanism to keep the airways and lungs free of particles and pathogens. Baseline and stimulated mucin secretion from secretory airway epithelial cells need to be tightly regulated to prevent mucus hypersecretion and mucus plugging of the airways. It is well established that extracellular ATP is a potent stimulus for regulated mucus secretion. Previous studies revealed that ATP acts via metabotropic P2Y2 purinoreceptors on goblet cells. Extracellular ATP, however, is also a potent agonist for ionotropic P2X purinoreceptors. Expression of several P2X isoforms has been reported in airways, but cell type-specific expression and the function thereof remained elusive. With this study, we now provide evidence that P2X4 is the predominant P2X isoform expressed in secretory airway epithelial cells. After IL-13 treatment of either human primary tracheal epithelial cells or mice, P2X4 expression is upregulated in vitro and in vivo under conditions of chronic inflammation, mucous metaplasia, and hyperplasia. Upregulation of P2X4 is strongest in MUC5AC-positive goblet cells. Moreover, activation of P2X4 by extracellular ATP augments intracellular Ca2+ signals and mucin secretion, whereas Ca2+ signals and mucin secretion are dampened by inhibition of P2X4 receptors. These data provide new insights into the purinergic regulation of mucin secretion and add to the emerging picture that P2X receptors modulate exocytosis of large secretory organelles and secretion of macromolecular vesicle cargo.
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Affiliation(s)
| | - Kristin E Thompson
- Centre de Recherche Saint-Antoine, INSERM, Université Pierre et Marie Curie-Université Paris 06, Sorbonne Universités, Paris , France
| | - Kathrin Neuland
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Ana M Jaramillo
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Giorgio Fois
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Hanna Schmidt
- Institute of General Physiology, Ulm University , Ulm , Germany
| | | | - Wei Han
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Michael J Tuvim
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Burton F Dickey
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Paul Dietl
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University , Ulm , Germany
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7
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Zhang T, Huang J, Yi Y, Zhang X, Loor JJ, Cao Y, Shi H, Luo J. Akt Serine/Threonine Kinase 1 Regulates de Novo Fatty Acid Synthesis through the Mammalian Target of Rapamycin/Sterol Regulatory Element Binding Protein 1 Axis in Dairy Goat Mammary Epithelial Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:1197-1205. [PMID: 29323924 DOI: 10.1021/acs.jafc.7b05305] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Akt serine/threonine kinase acts as a central mediator in the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, regulating a series of biological processes. In lipid metabolism, Akt activation regulates a series of gene expressions, including genes related to intracellular fatty acid synthesis. However, the regulatory mechanisms of Akt in dairy goat mammary lipid metabolism have not been elaborated. In this study, the coding sequences of goat Akt1 gene were cloned and analyzed. Gene expression of Akt1 in different lactation stages was also investigated. For in vitro studies, a eukaryotic expression vector of Akt1 was constructed and transfected to goat mammary epithelial cells (GMECs), and specific inhibitors of Akt/mammalian target of rapamycin (mTOR) signaling were applied to GMECs. Results showed that Akt1 protein was highly conserved, and its mRNA was highly expressed in midlactation. In vitro studies indicated that Akt1 phosphorylation activated mTOR and subsequently enhanced sterol regulatory element binding protein 1 (SREBP1), thus increasing intracellular triacylglycerol content. Inhibition of Akt/mTOR signaling down-regulated the gene expression of lipogenic genes. Overall, Akt1 plays an important role in regulating de novo fatty acid synthesis in goat mammary epithelial cells, and this process probably is through the mTOR/SREBP1 axis.
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Affiliation(s)
- Tianying Zhang
- Shanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University , Yangling, Shaanxi 712100, PR China
| | - Jiangtao Huang
- Shanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University , Yangling, Shaanxi 712100, PR China
| | - Yongqing Yi
- Shanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University , Yangling, Shaanxi 712100, PR China
| | - Xueying Zhang
- Shanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University , Yangling, Shaanxi 712100, PR China
| | - Juan J Loor
- Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois , Urbana, 61801 Illinois, United States
| | - Yanhong Cao
- Guangxi Institute of Animal Science , Nanning, Guangxi 535001, China
| | - Huaiping Shi
- Shanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University , Yangling, Shaanxi 712100, PR China
| | - Jun Luo
- Shanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University , Yangling, Shaanxi 712100, PR China
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8
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Fois G, Winkelmann VE, Bareis L, Staudenmaier L, Hecht E, Ziller C, Ehinger K, Schymeinsky J, Kranz C, Frick M. ATP is stored in lamellar bodies to activate vesicular P2X 4 in an autocrine fashion upon exocytosis. J Gen Physiol 2017; 150:277-291. [PMID: 29282210 PMCID: PMC5806682 DOI: 10.1085/jgp.201711870] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/12/2017] [Accepted: 11/17/2017] [Indexed: 12/14/2022] Open
Abstract
P2X4 receptor activation facilitates secretion of pulmonary surfactant from secretory vesicles called lamellar bodies in alveolar epithelial cells. Fois et al. reveal that P2X4 receptors on the lamellar body membranes are activated by ATP stored within the vesicles themselves upon vesicle exocytosis. Vesicular P2X4 receptors are known to facilitate secretion and activation of pulmonary surfactant in the alveoli of the lungs. P2X4 receptors are expressed in the membrane of lamellar bodies (LBs), large secretory lysosomes that store lung surfactant in alveolar type II epithelial cells, and become inserted into the plasma membrane after exocytosis. Subsequent activation of P2X4 receptors by adenosine triphosphate (ATP) results in local fusion-activated cation entry (FACE), facilitating fusion pore dilation, surfactant secretion, and surfactant activation. Despite the importance of ATP in the alveoli, and hence lung function, the origin of ATP in the alveoli is still elusive. In this study, we demonstrate that ATP is stored within LBs themselves at a concentration of ∼1.9 mM. ATP is loaded into LBs by the vesicular nucleotide transporter but does not activate P2X4 receptors because of the low intraluminal pH (5.5). However, the rise in intravesicular pH after opening of the exocytic fusion pore results in immediate activation of vesicular P2X4 by vesicular ATP. Our data suggest a new model in which agonist (ATP) and receptor (P2X4) are located in the same intracellular compartment (LB), protected from premature degradation (ATP) and activation (P2X4), and ideally placed to ensure coordinated and timely receptor activation as soon as fusion occurs to facilitate surfactant secretion.
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Affiliation(s)
- Giorgio Fois
- Institute of General Physiology, Ulm University, Ulm, Germany
| | | | - Lara Bareis
- Institute of General Physiology, Ulm University, Ulm, Germany
| | | | - Elena Hecht
- Institute of General Physiology, Ulm University, Ulm, Germany
| | - Charlotte Ziller
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Ulm, Germany
| | | | - Jürgen Schymeinsky
- Immunology and Respiratory Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Christine Kranz
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Ulm, Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University, Ulm, Germany
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9
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Lu R, Wilson JM. Rab14 specifies the apical membrane through Arf6-mediated regulation of lipid domains and Cdc42. Sci Rep 2016; 6:38249. [PMID: 27901125 PMCID: PMC5128791 DOI: 10.1038/srep38249] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 11/07/2016] [Indexed: 12/13/2022] Open
Abstract
The generation of cell polarity is essential for the development of multi-cellular organisms as well as for the function of epithelial organs in the mature animal. Small GTPases regulate the establishment and maintenance of polarity through effects on cytoskeleton, membrane trafficking, and signaling. Using short-term 3-dimensional culture of MDCK cells, we find that the small GTPase Rab14 is required for apical membrane specification. Rab14 knockdown results in disruption of polarized lipid domains and failure of the Par/aPKC/Cdc42 polarity complex to localize to the apical membrane. These effects are mediated through tight control of lipid localization, as overexpression of the phosphatidylinositol 4-phosphate 5-kinase α [PtdIns(4)P5K] activator Arf6 or PtdIns(4)P5K alone, or treatment with the phosphatidylinositol 3-kinase (PtdInsI3K) inhibitor wortmannin, rescued the multiple-apical domain phenotype observed after Rab14 knockdown. Rab14 also co-immunoprecipitates and colocalizes with the small GTPase Cdc42, and Rab14 knockdown results in increased Cdc42 activity. Furthermore, Rab14 regulates trafficking of vesicles to the apical domain, mitotic spindle orientation, and midbody position, consistent with Rab14’s reported localization to the midbody as well as its effects upon Cdc42. These results position Rab14 at the top of a molecular cascade that regulates the establishment of cell polarity.
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Affiliation(s)
- Ruifeng Lu
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ 85724, USA
| | - Jean M Wilson
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ 85724, USA
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10
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Olmeda B, Martínez-Calle M, Pérez-Gil J. Pulmonary surfactant metabolism in the alveolar airspace: Biogenesis, extracellular conversions, recycling. Ann Anat 2016; 209:78-92. [PMID: 27773772 DOI: 10.1016/j.aanat.2016.09.008] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/22/2016] [Accepted: 09/25/2016] [Indexed: 01/03/2023]
Abstract
Pulmonary surfactant is a lipid-protein complex that lines and stabilizes the respiratory interface in the alveoli, allowing for gas exchange during the breathing cycle. At the same time, surfactant constitutes the first line of lung defense against pathogens. This review presents an updated view on the processes involved in biogenesis and intracellular processing of newly synthesized and recycled surfactant components, as well as on the extracellular surfactant transformations before and after the formation of the surface active film at the air-water interface. Special attention is paid to the crucial regulation of surfactant homeostasis, because its disruption is associated with several lung pathologies.
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Affiliation(s)
- Bárbara Olmeda
- Department of Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, 28040 Madrid, Spain
| | - Marta Martínez-Calle
- Department of Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, 28040 Madrid, Spain
| | - Jesus Pérez-Gil
- Department of Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, 28040 Madrid, Spain.
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11
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Li R, Tan S, Yu M, Jundt MC, Zhang S, Wu M. Annexin A2 Regulates Autophagy in Pseudomonas aeruginosa Infection through the Akt1-mTOR-ULK1/2 Signaling Pathway. THE JOURNAL OF IMMUNOLOGY 2015; 195:3901-11. [PMID: 26371245 DOI: 10.4049/jimmunol.1500967] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 08/06/2015] [Indexed: 02/05/2023]
Abstract
Earlier studies reported that a cell membrane protein, Annexin A2 (AnxA2), plays multiple roles in the development, invasion, and metastasis of cancer. Recent studies demonstrated that AnxA2 also functions in immunity against infection, but the underlying mechanism remains largely elusive. Using a mouse infection model, we reveal a crucial role for AnxA2 in host defense against Pseudomonas aeruginosa, as anxa2(-/-) mice manifested severe lung injury, systemic dissemination, and increased mortality compared with wild-type littermates. In addition, anxa2(-/-) mice exhibited elevated inflammatory cytokines (TNF-α, IL-6, IL-1β, and IFN-γ), decreased bacterial clearance by macrophages, and increased superoxide release in the lung. We further identified an unexpected molecular interaction between AnxA2 and Fam13A, which activated Rho GTPase. P. aeruginosa infection induced autophagosome formation by inhibiting Akt1 and mTOR. Our results indicate that AnxA2 regulates autophagy, thereby contributing to host immunity against bacteria through the Akt1-mTOR-ULK1/2 signaling pathway.
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Affiliation(s)
- Rongpeng Li
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, ND 58203; College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing 211800, People's Republic of China
| | - Shirui Tan
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, ND 58203; College of Agriculture, Yunnan University, Kunming 650091, People's Republic of China
| | - Min Yu
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, ND 58203; Department of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, People's Republic of China; and
| | - Michael C Jundt
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, ND 58203
| | - Shuang Zhang
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, ND 58203; State Key Laboratory of Biotherapy and Cancer Center/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Min Wu
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, ND 58203;
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12
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A functional proteomics approach to the comprehension of sarcoidosis. J Proteomics 2015; 128:375-87. [PMID: 26342673 DOI: 10.1016/j.jprot.2015.08.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 07/30/2015] [Accepted: 08/19/2015] [Indexed: 12/22/2022]
Abstract
Pulmonary sarcoidosis (Sar) is an idiopathic disease histologically typified by non-caseating epitheliod cell sarcoid granulomas. A cohort of 37 Sar patients with chronic persistent pulmonary disease was described in this study. BAL protein profiles from 9 of these Sar patients were compared with those from 8 smoker (SC) and 10 no-smoker controls (NSC) by proteomic approach. Principal Component Analysis was performed to clusterize the samples in the corresponding conditions highlighting a differential pattern profiles primarily in Sar than SC. Spot identification reveals thirty-four unique proteins involved in lipid, mineral, and vitamin Dmetabolism, and immuneregulation of macrophage function. Enrichment analysis has been elaborated by MetaCore, revealing 14-3-3ε, α1-antitrypsin, GSTP1, and ApoA1 as "central hubs". Process Network as well as Pathway Maps underline proteins involved in immune response and inflammation induced by complement system, innate inflammatory response and IL-6signalling. Disease Biomarker Network highlights Tuberculosis and COPD as pathologies that share biomarkers with sarcoidosis. In conclusion, Sar protein expression profile seems more similar to that of NSC than SC, conversely to other ILDs. Moreover, Disease Biomarker Network revealed several common features between Sar and TB, exhorting to orientate the future proteomics investigations also in comparative BALF analysis of Sar and TB.
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13
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Bydoun M, Waisman DM. On the contribution of S100A10 and annexin A2 to plasminogen activation and oncogenesis: an enduring ambiguity. Future Oncol 2014; 10:2469-79. [DOI: 10.2217/fon.14.163] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ABSTRACT Plasminogen receptors are becoming increasingly relevant in regulating many diseases such as cancer, stroke and inflammation. However, controversy has emerged concerning the putative role of some receptors, in particular annexin A2, in binding plasminogen. Several reports failed to account for the effects of annexin A2 on the stability and conformation of its binding partner S100A10. This has created an enduring ambiguity as to the actual function of annexin A2 in plasmin regulation. Supported by a long line of evidence, we conclude that S100A10, and not annexin A2, is the primary plasminogen receptor within the annexin A2-S100A10 complex and contributes to the plasmin-mediated effects that were originally ascribed to annexin A2.
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Affiliation(s)
- Moamen Bydoun
- Department of Pathology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 1500, Halifax, Nova Scotia, B3H 4R2, Canada
| | - David M Waisman
- Department of Pathology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 1500, Halifax, Nova Scotia, B3H 4R2, Canada
- Department of Biochemistry & Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, PO Box 1500, Halifax, Nova Scotia, B3H 4R2, Canada
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14
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Córdoba-Valdés F, Castañeda-Priego R, Timmer J, Fleck C. The ratio of the lateral correlation length and particle radius determines the density profile of spherical molecules near a fluctuating membrane. SOFT MATTER 2014; 10:8475-8481. [PMID: 25238488 DOI: 10.1039/c4sm01550a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Interactions between membranes and molecules are important for many biological processes, e.g., transport of molecules across cell membranes. However, the detailed physical description of the membrane-biomolecule system remains a challenge and simplified schemes allow capturing its main intrinsic features. In this work, by means of Monte Carlo computer simulations, we systematically study the distribution of uncharged spherical molecules in contact with a flexible surface. Our results show that the distribution for finite size particles has the same simple functional form as the one obtained for point-like particles and depends only on the ratio of the lateral correlation length of the membrane and the radius of the molecules.
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Affiliation(s)
- Fidel Córdoba-Valdés
- UPIIG-IPN, Mineral de Valenciana 200, 36275 Silao de la Victoria, Guanajuato, Mexico
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15
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Annexin A2 heterotetramer: structure and function. Int J Mol Sci 2013; 14:6259-305. [PMID: 23519104 PMCID: PMC3634455 DOI: 10.3390/ijms14036259] [Citation(s) in RCA: 222] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 03/02/2013] [Accepted: 03/05/2013] [Indexed: 12/12/2022] Open
Abstract
Annexin A2 is a pleiotropic calcium- and anionic phospholipid-binding protein that exists as a monomer and as a heterotetrameric complex with the plasminogen receptor protein, S100A10. Annexin A2 has been proposed to play a key role in many processes including exocytosis, endocytosis, membrane organization, ion channel conductance, and also to link F-actin cytoskeleton to the plasma membrane. Despite an impressive list of potential binding partners and regulatory activities, it was somewhat unexpected that the annexin A2-null mouse should show a relatively benign phenotype. Studies with the annexin A2-null mouse have suggested important functions for annexin A2 and the heterotetramer in fibrinolysis, in the regulation of the LDL receptor and in cellular redox regulation. However, the demonstration that depletion of annexin A2 causes the depletion of several other proteins including S100A10, fascin and affects the expression of at least sixty-one genes has confounded the reports of its function. In this review we will discuss the annexin A2 structure and function and its proposed physiological and pathological roles.
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16
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Peng X, Wang Y, Kolli S, Deng J, Li L, Wang Z, Raj JU, Gou D. Physical and functional interaction between the ID1 and p65 for activation of NF-κB. Am J Physiol Cell Physiol 2012; 303:C267-77. [PMID: 22592405 DOI: 10.1152/ajpcell.00365.2011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Inhibitor of differentiation or DNA binding-1 (ID1) is an important helix-loop-helix (HLH) transcription factor involved in diverse biological functions including cell differentiation, proliferation, apoptosis, and senescence. Recently, it was reported that ID1 can activate the NF-κB signaling pathway in a variety of cancer cells and a T cell line, but the mechanisms involved in ID1-mediated transactivation of NF-κB are not clear. In this study, we demonstrate by both in vitro pull-down assays and a cell-based in vivo two-hybrid system that ID1-mediated NF-κB activation is due to its physical interaction with p65. We have identified that the transcriptional activation domain (TAD) in p65 and the HLH domain in ID1 are vital for their interaction. Interestingly, a single site mutation (Leu76) in the HLH domain of ID1 protein drastically decreased its ability to bind with p65. Using a dual-luciferase assay, we demonstrated that the interaction between ID1 and p65 modulates activation of the NF-κB signaling pathway in vivo. In addition, we demonstrated that, by affecting the nuclear translocation of p65, ID1 is essential in regulating TNF-α-induced p65 recruitment to its downstream target, the cellular inhibitor of apoptosis protein 2 (cIAP2) promoter.
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Affiliation(s)
- Xiao Peng
- College of Life Sciences, Shenzhen University, Shenzhen, China
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17
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Qi J, Mu D. MicroRNAs and lung cancers: from pathogenesis to clinical implications. Front Med 2012; 6:134-55. [PMID: 22528868 DOI: 10.1007/s11684-012-0188-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 02/08/2012] [Indexed: 02/07/2023]
Abstract
Lung cancer is the leading cause of cancer-related deaths in the US and worldwide. Better understanding of the disease is warranted for improvement in clinical management. Here we summarize the functions of small-RNA-based, posttranscriptional gene regulators, i.e. microRNAs, in the pathogenesis of lung cancers. We discuss the microRNAs that play oncogenic as well as tumor suppressive roles. We also touch on the value of microRNAs as markers for diagnosis, prognosis and the promising field of microRNA-based novel therapies for lung cancers.
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Affiliation(s)
- Ji Qi
- Department of Pathology, Pennsylvania State College of Medicine, Hershey, PA 17033, USA
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18
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Kanzaki H, Ito S, Hanafusa H, Jitsumori Y, Tamaru S, Shimizu K, Ouchida M. Identification of direct targets for the miR-17-92 cluster by proteomic analysis. Proteomics 2011; 11:3531-9. [DOI: 10.1002/pmic.201000501] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 05/02/2011] [Accepted: 06/08/2011] [Indexed: 01/07/2023]
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19
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Zhang L, Yu K, Robert KW, DeBolt KM, Hong N, Tao JQ, Fukuda M, Fisher AB, Huang S. Rab38 targets to lamellar bodies and normalizes their sizes in lung alveolar type II epithelial cells. Am J Physiol Lung Cell Mol Physiol 2011; 301:L461-77. [PMID: 21764986 DOI: 10.1152/ajplung.00056.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Rab38 is a rat Hermansky-Pudlak syndrome gene that plays an important role in surfactant homeostasis in alveolar type II (ATII) pneumocytes. We examined Rab38 function in regulating lamellar body (LB) morphology in ATII cells. Quantitative electron microscopy revealed that LBs in ATII cells were ∼77% larger in Rab38-null fawn-hooded hypertension (FHH) than control Sprague-Dawley (SD) rats. Rab38 protein expression was restricted in lung epithelial cells but was not found in primary endothelial cells. In SD ATII cells, Rab38 protein level gradually declined during 5 days in culture. Importantly, endogenous Rab38 was present in LB fractions purified from SD rat lungs, and transiently expressed enhanced green fluorescent protein (EGFP)-tagged Rab38 labeled only the limiting membranes of a subpopulation (∼30%) of LBs in cultured ATII cells. This selective targeting was abolished by point mutations to EGFP-Rab38 and was not shared by Rab7 and Rab4b, which also function in the ATII cells. Using confocal microscopy, we established a method for quantitative evaluation of the enlarged LB phenotype temporally preserved in cultured FHH ATII cells. A direct causal relationship was established when the enlarged LB phenotype was reserved and then rescued by transiently reexpressed EGFP-Rab38 in cultured FHH ATII cells. This rescuing effect was associated with dynamic EGFP-Rab38 targeting to and on LB limiting membranes. We conclude that Rab38 plays an indispensible role in maintaining LB morphology and surfactant homeostasis in ATII pneumocytes.
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Affiliation(s)
- Linghui Zhang
- Institute for Environmental Medicine, University of Pennsylvania School of Medicine, Philadelphia, 19104-6068, USA
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20
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Korfei M, Schmitt S, Ruppert C, Henneke I, Markart P, Loeh B, Mahavadi P, Wygrecka M, Klepetko W, Fink L, Bonniaud P, Preissner KT, Lochnit G, Schaefer L, Seeger W, Guenther A. Comparative proteomic analysis of lung tissue from patients with idiopathic pulmonary fibrosis (IPF) and lung transplant donor lungs. J Proteome Res 2011; 10:2185-205. [PMID: 21319792 DOI: 10.1021/pr1009355] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease for which no effective therapy exists to date. To identify the molecular mechanisms underlying IPF, we performed comparative proteome analysis of lung tissue from patients with sporadic IPF (n = 14) and human donor lungs (controls, n = 10) using two-dimensional gel electrophoresis and MALDI-TOF-MS. Eighty-nine differentially expressed proteins were identified, from which 51 were up-regulated and 38 down-regulated in IPF. Increased expression of markers for the unfolded protein response (UPR), heat-shock proteins, and DNA damage stress markers indicated a chronic cell stress-response in IPF lungs. By means of immunohistochemistry, induction of UPR markers was encountered in type-II alveolar epithelial cells of IPF but not of control lungs. In contrast, up-regulation of heat-shock protein 27 (Hsp27) was exclusively observed in proliferating bronchiolar basal cells and associated with aberrant re-epithelialization at the bronchiolo-alveolar junctions. Among the down-regulated proteins in IPF were antioxidants, members of the annexin family, and structural epithelial proteins. In summary, our results indicate that IPF is characterized by epithelial cell injury, apoptosis, and aberrant epithelial proliferation.
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Affiliation(s)
- Martina Korfei
- University of Giessen Lung Center, Department of Internal Medicine II, Klinikstrasse 36, Justus-Liebig-University Giessen, Germany
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21
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Bolasco G, Tracey-White DC, Tolmachova T, Thorley AJ, Tetley TD, Seabra MC, Hume AN. Loss of Rab27 function results in abnormal lung epithelium structure in mice. Am J Physiol Cell Physiol 2010; 300:C466-76. [PMID: 21160031 PMCID: PMC3063958 DOI: 10.1152/ajpcell.00446.2010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Rab27 small GTPases regulate secretion and movement of lysosome-related organelles such as T cell cytolytic granules and platelet-dense granules. Previous studies indicated that Rab27a and Rab27b are expressed in the murine lung suggesting that they regulate secretory processes in the lung. Consistent with those studies, we found that Rab27a and Rab27b are expressed in cell types that contain secretory granules: alveolar epithelial type II (AEII) and Clara cells. We then used Rab27a/Rab27b double knockout (DKO) mice to examine the functional consequence of loss of Rab27 proteins in the murine lung. Light and electron microscopy revealed a number of morphological changes in lungs from DKO mice when compared with those in control animals. In aged DKO mice we observed atrophy of the bronchiolar and alveolar epithelium with reduction of cells numbers, thinning of the bronchiolar epithelium and alveolar walls, and enlargement of alveolar airspaces. In these samples we also observed increased numbers of activated foamy alveolar macrophages and granulocyte containing infiltrates together with reduction in the numbers of Clara cells and AEII cells compared with control. At the ultrastructural level we observed accumulation of cytoplasmic membranes and vesicles in Clara cells. Meanwhile, AEII cells in DKO accumulated large mature lamellar bodies and lacked immature/precursor lamellar bodies. We hypothesize that the morphological changes observed at the ultrastructural level in DKO samples result from secretory defects in AEII and Clara cells and that over time these defects lead to atrophy of the epithelium.
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Affiliation(s)
- Giulia Bolasco
- Molecular Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
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