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Tu Z, Jin P, Wang Q, Feng Y, Chu X, Fu L, Hou S, Li W. Dynamically changed HSP70 after reperfusion following cerebral infarction in human and rats: correlation with p38 MAPK. Neuroreport 2024; 35:439-446. [PMID: 38597327 DOI: 10.1097/wnr.0000000000002022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
We aimed to clarify the correlation between dynamic change of blood HSP70 and the prognosis of thrombolysis in human and rats, so as to explain the neuroprotection and early warning role of HSP70 in cerebral ischemia-reperfusion. Forty-two patients with acute ischemic stroke were divided into two groups according to the time from onset to thrombolytic therapy: 0 h-3 h (27 patients) and 3-4.5 h group (15 patients). The level of HSP70 in serum before and after thrombolysis was detected by ELISA. Furthermore, a rat model was also used to mimic the ischemic stroke and reperfusion. Peripheral blood of rat samples was collected to detect the level of HSP70 using Elisa. Several signal proteins from MAPK signaling pathway including JNK, p38, ERK (p42/44) were detected at different time points by Western blot of brain tissue. Patients who underwent thrombolytic therapy within 0-3 h had the highest HSP70 level at 1 h after thrombolysis. The higher HSP70 after thrombolysis, the better the patient prognosis. NIHSS scores showed HSP70 was positively correlated with cerebral ischemia. The levels of ERK family (p42/44 MAPK) and p-JNK were decreased gradually along with the time suffering cerebral ischemia. P-ERK, JNK, p-p38 had dynamic changes with increased ischemic time in the middle cerebral artery occlusion model. Dynamic change of HSP70 level in blood may be a biological index that reflects the functional condition of cell survival for cerebral ischemia and estimating the prognostic conditions. Importantly, HSP70 levels in blood were positively correlated with the p38 MAPK pathway in brain tissue.
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Affiliation(s)
- Zhilan Tu
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
| | - Pengpeng Jin
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
- China Center of Medical Research and Innovation, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai
| | - Qinghua Wang
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
| | - Yanlin Feng
- Mathematics teaching and research Group, Weifang No.1 Middle School, Shandong Province
| | - Xinjuan Chu
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
| | - Lin Fu
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
| | - Shuangxing Hou
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
| | - Weiwei Li
- Department of Neurology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center
- Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai, China
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2
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Tian Q, Chung H, Wen D. The role of lipids in genome integrity and pluripotency. Biochem Soc Trans 2024; 52:639-650. [PMID: 38506536 PMCID: PMC11088914 DOI: 10.1042/bst20230479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 03/05/2024] [Accepted: 03/11/2024] [Indexed: 03/21/2024]
Abstract
Pluripotent stem cells (PSCs), comprising embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), offer immense potential for regenerative medicine due to their ability to differentiate into all cell types of the adult body. A critical aspect of harnessing this potential is understanding their metabolic requirements during derivation, maintenance, and differentiation in vitro. Traditional culture methods using fetal bovine serum often lead to issues such as heterogeneous cell populations and diminished pluripotency. Although the chemically-defined 2i/LIF medium has provided solutions to some of these challenges, prolonged culturing of these cells, especially female ESCs, raises concerns related to genome integrity. This review discusses the pivotal role of lipids in genome stability and pluripotency of stem cells. Notably, the introduction of lipid-rich albumin, AlbuMAX, into the 2i/LIF culture medium offers a promising avenue for enhancing the genomic stability and pluripotency of cultured ESCs. We further explore the unique characteristics of lipid-induced pluripotent stem cells (LIP-ESCs), emphasizing their potential in regenerative medicine and pluripotency research.
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Affiliation(s)
- Qiyu Tian
- Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, U.S.A
| | - Hoyoung Chung
- Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, U.S.A
| | - Duancheng Wen
- Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, U.S.A
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3
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Zhong L, Gordillo M, Wang X, Qin Y, Huang Y, Soshnev A, Kumar R, Nanjangud G, James D, David Allis C, Evans T, Carey B, Wen D. Dual role of lipids for genome stability and pluripotency facilitates full potency of mouse embryonic stem cells. Protein Cell 2023; 14:591-602. [PMID: 37029701 PMCID: PMC10392030 DOI: 10.1093/procel/pwad008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 01/09/2023] [Indexed: 02/18/2023] Open
Abstract
While Mek1/2 and Gsk3β inhibition ("2i") supports the maintenance of murine embryonic stem cells (ESCs) in a homogenous naïve state, prolonged culture in 2i results in aneuploidy and DNA hypomethylation that impairs developmental potential. Additionally, 2i fails to support derivation and culture of fully potent female ESCs. Here we find that mouse ESCs cultured in 2i/LIF supplemented with lipid-rich albumin (AlbuMAX) undergo pluripotency transition yet maintain genomic stability and full potency over long-term culture. Mechanistically, lipids in AlbuMAX impact intracellular metabolism including nucleotide biosynthesis, lipid biogenesis, and TCA cycle intermediates, with enhanced expression of DNMT3s that prevent DNA hypomethylation. Lipids induce a formative-like pluripotent state through direct stimulation of Erk2 phosphorylation, which also alleviates X chromosome loss in female ESCs. Importantly, both male and female "all-ESC" mice can be generated from de novo derived ESCs using AlbuMAX-based media. Our findings underscore the importance of lipids to pluripotency and link nutrient cues to genome integrity in early development.
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Affiliation(s)
- Liangwen Zhong
- Department of Reproductive Medicine, Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Miriam Gordillo
- Department of Surgery, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
| | - Xingyi Wang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Yiren Qin
- Department of Reproductive Medicine, Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Yuanyuan Huang
- Department of Reproductive Medicine, Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Alexey Soshnev
- Laboratory of Chromatin Biology and Epigenetics, The Rockefeller University, New York, NY 10065, USA
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA
| | - Ritu Kumar
- Department of Surgery, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
- Gladstone Institutes, 1650 Owens St, San Francisco, CA 94158, USA
| | - Gouri Nanjangud
- Molecular Cytogenetics Core. Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Daylon James
- Department of Reproductive Medicine, Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - C David Allis
- Laboratory of Chromatin Biology and Epigenetics, The Rockefeller University, New York, NY 10065, USA
| | - Todd Evans
- Department of Surgery, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
| | - Bryce Carey
- Laboratory of Chromatin Biology and Epigenetics, The Rockefeller University, New York, NY 10065, USA
| | - Duancheng Wen
- Department of Reproductive Medicine, Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, NY 10065, USA
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Fernández-García P, Malet-Engra G, Torres M, Hanson D, Rosselló CA, Román R, Lladó V, Escribá PV. Evolving Diagnostic and Treatment Strategies for Pediatric CNS Tumors: The Impact of Lipid Metabolism. Biomedicines 2023; 11:biomedicines11051365. [PMID: 37239036 DOI: 10.3390/biomedicines11051365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/21/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Pediatric neurological tumors are a heterogeneous group of cancers, many of which carry a poor prognosis and lack a "standard of care" therapy. While they have similar anatomic locations, pediatric neurological tumors harbor specific molecular signatures that distinguish them from adult brain and other neurological cancers. Recent advances through the application of genetics and imaging tools have reshaped the molecular classification and treatment of pediatric neurological tumors, specifically considering the molecular alterations involved. A multidisciplinary effort is ongoing to develop new therapeutic strategies for these tumors, employing innovative and established approaches. Strikingly, there is increasing evidence that lipid metabolism is altered during the development of these types of tumors. Thus, in addition to targeted therapies focusing on classical oncogenes, new treatments are being developed based on a broad spectrum of strategies, ranging from vaccines to viral vectors, and melitherapy. This work reviews the current therapeutic landscape for pediatric brain tumors, considering new emerging treatments and ongoing clinical trials. In addition, the role of lipid metabolism in these neoplasms and its relevance for the development of novel therapies are discussed.
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Affiliation(s)
- Paula Fernández-García
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Laminar Pharmaceuticals, Isaac Newton, 07121 Palma de Mallorca, Spain
| | - Gema Malet-Engra
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Laminar Pharmaceuticals, Isaac Newton, 07121 Palma de Mallorca, Spain
| | - Manuel Torres
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
| | - Derek Hanson
- Hackensack Meridian Health, 343 Thornall Street, Edison, NJ 08837, USA
| | - Catalina A Rosselló
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Laminar Pharmaceuticals, Isaac Newton, 07121 Palma de Mallorca, Spain
| | - Ramón Román
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Laminar Pharmaceuticals, Isaac Newton, 07121 Palma de Mallorca, Spain
| | - Victoria Lladó
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Laminar Pharmaceuticals, Isaac Newton, 07121 Palma de Mallorca, Spain
| | - Pablo V Escribá
- Laboratory of Molecular Cell Biomedicine, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Laminar Pharmaceuticals, Isaac Newton, 07121 Palma de Mallorca, Spain
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5
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Bailey LS, Prajapati DV, Basso KB. Optimization of the Sulfo-Phospho-Vanillin Assay for Total Lipid Normalization in Untargeted Quantitative Lipidomic LC-MS/MS Applications. Anal Chem 2022; 94:17810-17818. [PMID: 36520113 DOI: 10.1021/acs.analchem.2c03488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Liquid chromatography (LC)-mass spectrometry (MS)/MS lipidomic normalization is generally performed by equalizing pre-extraction sample materials or via DNA or protein pre-quantitation methods, which have known measurement inaccuracies. We propose the use of the sulfo-phospho-vanillin assay (SPVA), a total lipid colorimetric analysis, as a pre-quantitation method to normalize lipids in lipidomic LC-MS/MS applications. The assay has been applied to a 300 μL well volume in a 96-well plate and tested using Avanti total lipid standards of porcine brain and E. coli. Assay parameters for lipid sample volume, sulfuric acid, vanillin/phosphoric acid, post-reaction incubation time, and wavelength are optimized for robust application to biologically sourced lipid samples. Standard test samples were prepared using three concentrations covering approximately 100 μg/mL range. The optimized assay yielded test sample errors less than 10%, indicating a precise and accurate assay performance. The test samples were then analyzed by LC-MS/MS and normalized using SPVA pre-quantitation and pseudo-mass normalization. The detected lipids showed smaller standard deviations and greater relative concentration differences compared to the pseudo-mass normalized lipids, showing promise as a normalization method.
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Affiliation(s)
- Laura S Bailey
- Mass Spectrometry Research and Education Center, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Dilip V Prajapati
- Mass Spectrometry Research and Education Center, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Kari B Basso
- Mass Spectrometry Research and Education Center, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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6
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Du K, Chen GH, Bai X, Chen L, Hu SQ, Li YH, Wang GZ, He JW, Lai SJ. Dynamics of transcriptome and chromatin accessibility revealed sequential regulation of potential transcription factors during the brown adipose tissue whitening in rabbits. Front Cell Dev Biol 2022; 10:981661. [PMID: 36225319 PMCID: PMC9548568 DOI: 10.3389/fcell.2022.981661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 09/07/2022] [Indexed: 11/13/2022] Open
Abstract
Brown adipose tissue (BAT) represents a valuable target for treating obesity in humans. BAT losses of thermogenic capacity and gains a “white adipose tissue-like (WAT-like)” phenotype (BAT whitening) under thermoneutral environments, which could lead to potential low therapy responsiveness in BAT-based obesity treatments. However, the epigenetic mechanisms of BAT whitening remain largely unknown. In this study, BATs were collected from rabbits at day0 (D0), D15, D85, and 2 years (Y2). RNA-sequencing (RNA-seq) and the assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) were performed to investigate transcriptome and chromatin accessibility of BATs at the four whitening stages, respectively. Our data showed that many genes and chromatin accessible regions (refer to as “peaks”) were identified as significantly changed during BAT whitening in rabbits. The BAT-selective genes downregulated while WAT-selective genes upregulated from D0 to Y2, and the de novo lipogenesis-related genes reached the highest expression levels at D85. Both the highly expressed genes and accessible regions in Y2 were significantly enriched in immune response-related signal pathways. Analysis of different relationships between peaks and their nearby genes found an increased proportion of the synchronous changes between chromatin accessibility and gene expression during BAT whitening. The synergistic changes between the chromatin accessibility of promoter and the gene expression were found in the key adipose genes. The upregulated genes which contained increased peaks were significantly enriched in the PI3K-Akt signaling pathway, steroid biosynthesis, TGF-beta signaling pathway, osteoclast differentiation, and dilated cardiomyopathy. Moreover, the footprinting analysis suggested that sequential regulation of potential transcription factors (TFs) mediated the loss of thermogenic phenotype and the gain of a WAT-like phenotype of BAT. In conclusion, our study provided the transcriptional and epigenetic frameworks for understanding BAT whitening in rabbits for the first time and might facilitate potential insights into BAT-based obesity treatments.
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Affiliation(s)
- Kun Du
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Guan-He Chen
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Xue Bai
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Li Chen
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Shen-Qiang Hu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Yan-Hong Li
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Guo-Ze Wang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, China
| | - Jing-Wei He
- Sichuan Animal Husbandry Station, Chengdu, China
| | - Song-Jia Lai
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, China
- *Correspondence: Song-Jia Lai,
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7
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Yuan X, Cui H, Jin Y, Zhao W, Liu X, Wang Y, Ding J, Liu L, Wen J, Zhao G. Fatty acid metabolism-related genes are associated with flavor-presenting aldehydes in Chinese local chicken. Front Genet 2022; 13:902180. [PMID: 36035160 PMCID: PMC9412053 DOI: 10.3389/fgene.2022.902180] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/11/2022] [Indexed: 11/20/2022] Open
Abstract
Aldehydes are primary volatile organic compounds (VOCs) in local Chinese chicken meat and contribute green grass, fatty, citrus, and bitter almond aromas to chicken meat. To understand the genetic basis of these aldehyde VOC aromas, we used approximately 500 Chinese Jingxing Yellow (JXY) chickens to conduct genome-wide association studies (GWAS) on the flavor traits with the data of single nucleotide polymorphisms (SNPs) and insertions and deletions (INDELs). In total, 501 association variants (253 SNPs and 248 INDELs) were found to be suggestively (SNPs: p-value < 2.77e-06 and INDELs: p-value < 3.78e-05) associated with total aldehydes (the sum of nine aldehydes), hexanal, heptanal, benzaldehyde, (E,E)-2,4-nonadienal, octanal, (E)-2-decenal, nonanal, decanal, and octadecanal. Of them, six SNPs and 23 INDELs reached a genome-wide significance level (SNPs: p-value < 1.38e-07 and INDELs: p-value < 1.89e-06). Potential candidate aldehyde genes were functionally annotated for lipid metabolism, especially fatty acid-related pathways and phospholipid-related gene ontology (GO) terms. Moreover, the GWAS analysis of total aldehydes, hexanal, and nonanal generated the most significant signals, and phenotypic content differed between different genotypes at candidate gene-related loci. For total aldehydes and hexanal traits, candidate genes were annotated based on the significant and suggestive variants on chromosomes 3 and 8 with highly polymorphic linkage blocks. The following candidate genes were also identified: GALM, MAP4K3, GPCPD1, RPS6KA2, CRLS1, ASAP1, TRMT6, SDC1, PUM2, ALDH9A1, MGST3, GMEB1, MECR, LDLRAP1, GPAM and ACSL5. We also found that polyunsaturated fatty acids (PUFAs) (C18:2n6c linoleic acid and C18:3n3 linolenic acid) were significantly correlated with total aldehydes and hexanal contents. PUFAs are important aldehyde precursors, and consistently, our results suggested that candidate genes involved in fatty acid pathways and phospholipid GO terms were identified in association loci. This work provides an understanding of the genetic basis of aldehyde formation, which is a key flavor-forming compound.
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Zhao X, Liu H, Pan Y, Liu Y, Zhang F, Ao H, Zhang J, Xing K, Wang C. Identification of Potential Candidate Genes From Co-Expression Module Analysis During Preadipocyte Differentiation in Landrace Pig. Front Genet 2022; 12:753725. [PMID: 35178067 PMCID: PMC8843850 DOI: 10.3389/fgene.2021.753725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 12/08/2021] [Indexed: 12/12/2022] Open
Abstract
Preadipocyte differentiation plays an important role in lipid deposition and affects fattening efficiency in pigs. In the present study, preadipocytes isolated from the subcutaneous adipose tissue of three Landrace piglets were induced into mature adipocytes in vitro. Gene clusters associated with fat deposition were investigated using RNA sequencing data at four time points during preadipocyte differentiation. Twenty-seven co-expression modules were subsequently constructed using weighted gene co-expression network analysis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses revealed three modules (blue, magenta, and brown) as being the most critical during preadipocyte differentiation. Based on these data and our previous differentially expressed gene analysis, angiopoietin-like 4 (ANGPTL4) was identified as a key regulator of preadipocyte differentiation and lipid metabolism. After inhibition of ANGPTL4, the expression of adipogenesis-related genes was reduced, except for that of lipoprotein lipase (LPL), which was negatively regulated by ANGPTL4 during preadipocyte differentiation. Our findings provide a new perspective to understand the mechanism of fat deposition.
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Affiliation(s)
- Xitong Zhao
- Beijing Shunxin Agriculture Co., Ltd., Beijing, China.,China Agricultural University, Beijing, China
| | - Huatao Liu
- China Agricultural University, Beijing, China
| | - Yongjie Pan
- Beijing Shunxin Agriculture Co., Ltd., Beijing, China
| | - Yibing Liu
- China Agricultural University, Beijing, China
| | | | - Hong Ao
- Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jibin Zhang
- City of Hope National Medical Center, Duarte, CA, United States
| | - Kai Xing
- Beijing University of Agriculture, Beijing, China
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Huang C, Ge F, Ma X, Dai R, Dingkao R, Zhaxi Z, Burenchao G, Bao P, Wu X, Guo X, Chu M, Yan P, Liang C. Comprehensive Analysis of mRNA, lncRNA, circRNA, and miRNA Expression Profiles and Their ceRNA Networks in the Longissimus Dorsi Muscle of Cattle-Yak and Yak. Front Genet 2021; 12:772557. [PMID: 34966412 PMCID: PMC8710697 DOI: 10.3389/fgene.2021.772557] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/15/2021] [Indexed: 12/18/2022] Open
Abstract
Cattle-yak, as the hybrid offspring of cattle (Bos taurus) and yak (Bos grunniens), demonstrates obvious heterosis in production performance. Male hybrid sterility has been focused on for a long time; however, the mRNAs and non-coding RNAs related to muscle development as well as their regulatory networks remain unclear. The phenotypic data showed that the production performance (i.e., body weight, withers height, body length, and chest girth) of cattle-yak was significantly better than that of the yak, and the economic benefits of the cattle-yak were higher under the same feeding conditions. Then, we detected the expression profiles of the longissimus dorsi muscle of cattle-yak and yak to systematically reveal the molecular basis using the high-throughput sequencing technology. Here, 7,126 mRNAs, 791 lncRNAs, and 1,057 circRNAs were identified to be differentially expressed between cattle-yaks and yaks in the longissimus dorsi muscle. These mRNAs, lncRNA targeted genes, and circRNA host genes were significantly enriched in myoblast differentiation and some signaling pathways related to muscle development (such as HIF-1 signaling pathway and PI3K-Akt signaling pathway). We constructed a competing endogenous RNA (ceRNA) network and found that some non-coding RNAs differentially expressed may be involved in the regulation of muscle traits. Taken together, this study may be used as a reference tool to provide the molecular basis for studying muscle development.
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Affiliation(s)
- Chun Huang
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Fei Ge
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiaoming Ma
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Rongfeng Dai
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Renqing Dingkao
- Livestock Institute of Gannan Tibetan Autonomous Prefecture, Hezuo, China
| | - Zhuoma Zhaxi
- Haixi Agricultural and Animal Husbandry Technology Extension Service Center, Qinghai, China
| | - Getu Burenchao
- Haixi Agricultural and Animal Husbandry Technology Extension Service Center, Qinghai, China
| | - Pengjia Bao
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiaoyun Wu
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xian Guo
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Min Chu
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Ping Yan
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Chunnian Liang
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
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10
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Yang Y, Zhai X, El Hiani Y. TRPML1-Emerging Roles in Cancer. Cells 2020; 9:E2682. [PMID: 33322223 PMCID: PMC7763474 DOI: 10.3390/cells9122682] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 02/06/2023] Open
Abstract
The mucolipin-1 (TRPML1) channel maintains lysosomal ionic homeostasis and regulates autophagic flux. Defects of TRPML1 lead to lysosomal storage diseases and neurodegeneration. In this report, we discuss emerging evidence pertaining to differential regulation of TRPML1 signaling pathways in cancer progression with the goal of leveraging the oncogenic potential of TRPML1 to inspire therapeutic interventions.
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Affiliation(s)
| | | | - Yassine El Hiani
- Department of Physiology and Biophysics, Dalhousie University Faculty of Medicine, Halifax, NS B3H 4R2, Canada; (Y.Y.); (X.Z.)
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11
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Huang D, Liu J, Eldridge RC, Gaul DA, Paine MRL, Uppal K, MacDonald TJ, Fernández FM. Lipidome signatures of metastasis in a transgenic mouse model of sonic hedgehog medulloblastoma. Anal Bioanal Chem 2020; 412:7017-7027. [PMID: 32794007 PMCID: PMC7982123 DOI: 10.1007/s00216-020-02837-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/17/2020] [Accepted: 07/21/2020] [Indexed: 12/20/2022]
Abstract
Medulloblastoma (MB), the most common malignant pediatric brain tumor, has high propensity to metastasize. Currently, the standard treatment for MB patients includes radiation therapy administered to the entire brain and spine for the purpose of treating or preventing against metastasis. Due to this aggressive treatment, the majority of long-term survivors will be left with permanent and debilitating neurocognitive impairment, for the 30-40% patients that fail to respond to treatment, all will relapse with terminal metastatic disease. An understanding of the underlying biology that drives MB metastasis is lacking, and is critically needed in order to develop targeted therapeutics for its prevention. To examine the metastatic biology of sonic hedgehog (SHH) MB, the human MB subgroup with the worst clinical outcome in children, we first generated a robust SmoA1-Math-GFP mouse model that reliably reproduces human SHH MB whereby metastases can be visualized under fluorescence microscopy. Lipidome alterations associated with metastasis were then investigated by applying ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) under positive ionization mode to primary tumor samples collected from mice without (n = 18) and with (n = 7) metastasis. Thirty-four discriminant lipids associated with SHH MB metastasis were successfully annotated, including ceramides (Cers), sphingomyelins (SMs), triacylglycerols (TGs), diacylglycerols (DGs), phosphatidylcholines (PCs), and phosphatidic acids (PAs). This study provides deeper insights into dysregulations of lipid metabolism associated with SHH MB metastatic progression, and thus serves as a guide toward novel targeted therapies.
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Affiliation(s)
- Danning Huang
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Jingbo Liu
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | | | - David A Gaul
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | | | - Karan Uppal
- Department of Medicine, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Tobey J MacDonald
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Facundo M Fernández
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
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12
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Zhu L, He S, Liu Y, Shi J, Xu J. Arabidopsis FAX1 mediated fatty acid export is required for the transcriptional regulation of anther development and pollen wall formation. PLANT MOLECULAR BIOLOGY 2020; 104:187-201. [PMID: 32681357 DOI: 10.1007/s11103-020-01036-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/12/2020] [Indexed: 05/25/2023]
Abstract
The mutation of FAX1 (Fatty Acid Export 1) disrupts ROS homeostasis and suppresses transcription activity of DYT1-TDF1-AMS-MS188 genetic network, leading to atypical tapetum PCD and defective pollen formation in Arabidopsis. Fatty acids (FAs) have multiple important biological functions and exert diverse cellular effects through modulating Reactive Oxygen Species (ROS) homeostasis. Arabidopsis FAX1 (Fatty Acid Export 1) mediates the export of de novo synthesized FA from chloroplast and loss of function of FAX1 impairs male fertility. However, mechanisms underlying the association of FAX1-mediated FA export with male sterility remain enigmatic. In this study, by using an integrated approach that included morphological, cytological, histological, and molecular analyses, we revealed that loss of function of FAX1 breaks cellular FA/lipid homeostasis, which disrupts ROS homeostasis and suppresses transcriptional activation of the DYT1-TDF1-AMS-MS188 genetic network of anther development, impairing tapetum development and pollen wall formation, and resulting in male sterility. This study provides new insights into the regulatory network for male reproduction in plants, highlighting an important role of FA export-mediated ROS homeostasis in the process.
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Affiliation(s)
- Lu Zhu
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Siyang He
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - YanYan Liu
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Jianxin Shi
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
| | - Jie Xu
- Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
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13
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Wang H, Zhong J, Zhang C, Chai Z, Cao H, Wang J, Zhu J, Wang J, Ji Q. The whole-transcriptome landscape of muscle and adipose tissues reveals the ceRNA regulation network related to intramuscular fat deposition in yak. BMC Genomics 2020; 21:347. [PMID: 32381004 PMCID: PMC7203869 DOI: 10.1186/s12864-020-6757-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 04/27/2020] [Indexed: 02/07/2023] Open
Abstract
Background The Intramuscular fat (IMF) content in meat products, which is positively correlated with meat quality, is an important trait considered by consumers. The regulation of IMF deposition is species specific. However, the IMF-deposition-related mRNA and non-coding RNA and their regulatory network in yak (Bos grunniens) remain unknown. High-throughput sequencing technology provides a powerful approach for analyzing the association between transcriptome-related differences and specific traits in animals. Thus, the whole transcriptomes of yak muscle and adipose tissues were screened and analyzed to elucidate the IMF deposition-related genes. The muscle tissues were used for IMF content measurements. Results Significant differences were observed between the 0.5- and 2.5-year-old yaks. Several mRNAs, miRNAs, lncRNAs and circRNAs were generally expressed in both muscle and adipose tissues. Between the 0.5- and 2.5-year-old yaks, 149 mRNAs, 62 miRNAs, 4 lncRNAs, and 223 circRNAs were differentially expressed in muscle tissue, and 72 mRNAs, 15 miRNAs, 9 lncRNAs, and 211 circRNAs were differentially expressed in adipose tissue. KEGG annotation revelved that these differentially expressed genes were related to pathways that maintain normal biological functions of muscle and adipose tissues. Moreover, 16 mRNAs, 5 miRNAs, 3 lncRNAs, and 5 circRNAs were co-differentially expressed in both types of tissue. We suspected that these co-differentially expressed genes were involved in IMF-deposition in the yak. Additionally, LPL, ACADL, SCD, and FASN, which were previously shown to be associated with the IMF content, were identified in the competing endogenous RNA (ceRNA) regulatory network that was constructed on the basis of the IMF deposition-related genes. Three ceRNA subnetworks also revealed that TCONS-00016416 and its target SIRT1 “talk” to each other through the same miR-381-y and miR-208 response elements, whereas TCONS-00061798 and its target PRKCA, and TCONS-00084092 and its target LPL “talk” to each other through miR-122-x and miR-499-y response elements, respectively. Conclusion Taken together, our results reveal the potential mRNA and noncoding RNAs involved in IMF deposition in the yak, providing a useful resource for further research on IMF deposition in this animal species.
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Affiliation(s)
- Hui Wang
- Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China.,Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China
| | - Jincheng Zhong
- Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China. .,Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China.
| | - Chengfu Zhang
- State Key Laboratory of Hulless Barley and Yak Germplasm Resources and Genetic Improvement, the Tibet Academy of Agricultural and Animal Husbandry Science , Lhasa, Tibet, 850000, People's Republic of China
| | - Zhixin Chai
- Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China.,Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China
| | - Hanwen Cao
- State Key Laboratory of Hulless Barley and Yak Germplasm Resources and Genetic Improvement, the Tibet Academy of Agricultural and Animal Husbandry Science , Lhasa, Tibet, 850000, People's Republic of China
| | - Jikun Wang
- Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China.,Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China
| | - Jiangjiang Zhu
- Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China.,Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China
| | - Jiabo Wang
- Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China.,Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu, Sichuan, 610041, People's Republic of China
| | - Qiumei Ji
- State Key Laboratory of Hulless Barley and Yak Germplasm Resources and Genetic Improvement, the Tibet Academy of Agricultural and Animal Husbandry Science , Lhasa, Tibet, 850000, People's Republic of China.
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14
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Structural snapshots of RAF kinase interactions. Biochem Soc Trans 2018; 46:1393-1406. [PMID: 30381334 DOI: 10.1042/bst20170528] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 07/25/2018] [Accepted: 07/30/2018] [Indexed: 02/07/2023]
Abstract
RAF (rapidly accelerated fibrosarcoma) Ser/Thr kinases (ARAF, BRAF, and CRAF) link the RAS (rat sarcoma) protein family with the MAPK (mitogen-activated protein kinase) pathway and control cell growth, differentiation, development, aging, and tumorigenesis. Their activity is specifically modulated by protein-protein interactions, post-translational modifications, and conformational changes in specific spatiotemporal patterns via various upstream regulators, including the kinases, phosphatase, GTPases, and scaffold and modulator proteins. Dephosphorylation of Ser-259 (CRAF numbering) and dissociation of 14-3-3 release the RAF regulatory domains RAS-binding domain and cysteine-rich domain for interaction with RAS-GTP and membrane lipids. This, in turn, results in RAF phosphorylation at Ser-621 and 14-3-3 reassociation, followed by its dimerization and ultimately substrate binding and phosphorylation. This review focuses on structural understanding of how distinct binding partners trigger a cascade of molecular events that induces RAF kinase activation.
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15
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Ji N, Pan S, Shao C, Chen Y, Zhang Z, Wang R, Qiu Y, Jin M, Kong D. Spinacetin Suppresses the Mast Cell Activation and Passive Cutaneous Anaphylaxis in Mouse Model. Front Pharmacol 2018; 9:824. [PMID: 30104977 PMCID: PMC6077219 DOI: 10.3389/fphar.2018.00824] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 07/09/2018] [Indexed: 12/21/2022] Open
Abstract
We previously reported the anti-inflammatory and anti-asthmatic activities of the extract of the Inula japonica Thunb. Aiming for discovery of a novel anti-inflammatory compound, we isolated spinacetin from the extract and investigated its in vitro and in vivo anti-inflammatory effect and the related mechanism. Effect of spinacetin on the Syk signaling pathway was studied in bone marrow-derived mast cells (BMMCs), and that on the nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) was investigated in Rat basophilic leukemia (RBL)-2H3 cells and human mast cell line (HMC-1). The in vivo anti-inflammatory activity was assessed with passive cutaneous anaphylaxis (PCA) reaction assay. Spinacetin significantly inhibited the release of histamine, and production of inflammatory mediators such as leukotriene C4 (LTC4) and interlukin-6 (IL-6) in IgE/Ag stimulated BMMCs. Analysis of the signaling pathways demonstrated that spinacetin inhibited activation of Syk, linker of activated T cells (LAT), phospholipase Cγ (PLCγ), cytosolic phospholipase A2 (cPLA2), MAPKs, Akt/NF-κB, and intracellular Ca2+ mobilization but with no effect on Fyn and Lyn. On the other hand, spinacetin suppressed IgE/Ag-induced activation of RBL-2H3 cells with inhibition against phosphorylation of extracellular signal regulated-protein kinase (ERK), c-Jun-NH2-terminal kinase (JNK), p38 MAPKs, PLCγ, translocation of cPLA2, and Akt/IκBα/NF-κB signal. However, spinacetin had no effect on PMA and A23187-induced activation of HMC-1. Furthermore, oral administration of spinacetin dose-dependently attenuated IgE/Ag-mediated PCA reaction in mouse model. Taken together, spinacetin showed the activities in preventing inflammatory processes, which might be at least partially attributed to the abolishment of Syk-dependent activation of IgE/Ag-mediated mast cells.
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Affiliation(s)
- Ning Ji
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Shunli Pan
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Chen Shao
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Yufen Chen
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China.,Pharmacy Department, Tanggu Hospital of Infectious Diseases of Tianjin Binhai New Area, Tianjin, China
| | - Zhe Zhang
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Ran Wang
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Yuling Qiu
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Meihua Jin
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Dexin Kong
- Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin, China
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16
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Role of MAPKs in HSP70's Protection against Heat Stress-Induced Injury in Rat Small Intestine. BIOMED RESEARCH INTERNATIONAL 2018; 2018:1571406. [PMID: 30112361 PMCID: PMC6077665 DOI: 10.1155/2018/1571406] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 06/18/2018] [Accepted: 06/27/2018] [Indexed: 02/06/2023]
Abstract
Aim To evaluate the role of heat shock protein 70 (HSP70) on the MAPK pathway activation with quercetin treatment and its protection against small intestine impairments of heat stressed rats. Methods Forty-eight male Sprague-Dawley rats aged 6 weeks were randomized to three groups (n=16/group), namely, control (CON), heat stress (HS), and heat stress + quercetin (HQ). The experiment lasted for 14 days with daily 50 min of heat stress treatment (43°C) for the HS and HQ groups. Rats of HQ group were intragastrically given 0.5 ml quercetin solution (50 mg/kg body weight) before the heat stress treatment. Half of the animals were sacrificed on day 7 and the rest on day 14 for tissue sampling. Intestinal morphology, small intestine morphology and permeability, protein expression of HSP70, phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and caspase-3 activity were examined. Results Heat stress caused morphological damage to the small intestine and increased intestinal permeability. HSP70 expression and MAPK activity in the small intestine were increased by heat stress. Inhibition of HSP70 by quercetin did not change intestinal permeability compared with the HS group but aggravated intestinal injury and affected the activation of MAPKs and caspase-3. Conclusions HSP70 may modulate stress-activated signaling and acts in a protective manner via MAPK signaling. Affecting HSP70 protective mechanisms could be useful for protection against heat stress-induced injury in rat small intestine.
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17
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Kos MZ, Carless MA, Peralta J, Curran JE, Quillen EE, Almeida M, Blackburn A, Blondell L, Roalf DR, Pogue-Geile MF, Gur RC, Göring HHH, Nimgaonkar VL, Gur RE, Almasy L. Exome sequences of multiplex, multigenerational families reveal schizophrenia risk loci with potential implications for neurocognitive performance. Am J Med Genet B Neuropsychiatr Genet 2017; 174:817-827. [PMID: 28902459 PMCID: PMC5760172 DOI: 10.1002/ajmg.b.32597] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 08/16/2017] [Indexed: 12/28/2022]
Abstract
Schizophrenia is a serious mental illness, involving disruptions in thought and behavior, with a worldwide prevalence of about one percent. Although highly heritable, much of the genetic liability of schizophrenia is yet to be explained. We searched for susceptibility loci in multiplex, multigenerational families affected by schizophrenia, targeting protein-altering variation with in silico predicted functional effects. Exome sequencing was performed on 136 samples from eight European-American families, including 23 individuals diagnosed with schizophrenia or schizoaffective disorder. In total, 11,878 non-synonymous variants from 6,396 genes were tested for their association with schizophrenia spectrum disorders. Pathway enrichment analyses were conducted on gene-based test results, protein-protein interaction (PPI) networks, and epistatic effects. Using a significance threshold of FDR < 0.1, association was detected for rs10941112 (p = 2.1 × 10-5 ; q-value = 0.073) in AMACR, a gene involved in fatty acid metabolism and previously implicated in schizophrenia, with significant cis effects on gene expression (p = 5.5 × 10-4 ), including brain tissue data from the Genotype-Tissue Expression project (minimum p = 6.0 × 10-5 ). A second SNP, rs10378 located in TMEM176A, also shows risk effects in the exome data (p = 2.8 × 10-5 ; q-value = 0.073). PPIs among our top gene-based association results (p < 0.05; n = 359 genes) reveal significant enrichment of genes involved in NCAM-mediated neurite outgrowth (p = 3.0 × 10-5 ), while exome-wide SNP-SNP interaction effects for rs10941112 and rs10378 indicate a potential role for kinase-mediated signaling involved in memory and learning. In conclusion, these association results implicate AMACR and TMEM176A in schizophrenia risk, whose effects may be modulated by genes involved in synaptic plasticity and neurocognitive performance.
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Affiliation(s)
- Mark Z. Kos
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | - Melanie A. Carless
- Department of Genetics, Texas Biomedical Research Institute, San
Antonio, TX, USA
| | - Juan Peralta
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | - Joanne E. Curran
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | - Ellen E. Quillen
- Department of Genetics, Texas Biomedical Research Institute, San
Antonio, TX, USA
| | - Marcio Almeida
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | - August Blackburn
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | - Lucy Blondell
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | - David R. Roalf
- Department of Psychiatry, University of Pennsylvania School of
Medicine, Philadelphia, PA, USA
| | | | - Ruben C. Gur
- Department of Psychiatry, University of Pennsylvania School of
Medicine, Philadelphia, PA, USA
| | - Harald H. H. Göring
- South Texas Diabetes and Obesity Institute, The University of Texas
Rio Grande Valley, San Antonio and Brownsville, TX, USA
| | | | - Raquel E. Gur
- Department of Psychiatry, University of Pennsylvania School of
Medicine, Philadelphia, PA, USA
| | - Laura Almasy
- Departments of Genetics, University of Pennsylvania School of
Medicine, Philadelphia, PA, USA
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18
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Srikanth K, Lee E, Kwan A, Lim Y, Lee J, Jang G, Chung H. Transcriptome analysis and identification of significantly differentially expressed genes in Holstein calves subjected to severe thermal stress. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2017; 61:1993-2008. [PMID: 28900747 DOI: 10.1007/s00484-017-1392-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 06/01/2017] [Accepted: 06/02/2017] [Indexed: 06/07/2023]
Abstract
RNA-Seq analysis was used to characterize transcriptome response of Holstein calves to thermal stress. A total of eight animals aged between 2 and 3 months were randomly selected and subjected to thermal stress corresponding to a temperature humidity index of 95 in an environmentally controlled house for 12 h consecutively for 3 days. A set of 15,787 unigenes were found to be expressed and after a threshold of threefold change, and a Q value <0.05; 502, 394, and 376 genes were found to be differentially expressed on days 1, 2, and 3 out of which 343, 261 and 256 genes were upregulated and 159, 133, and 120 genes were downregulated. Only 356 genes out of these were expressed on all 3 days, and only they were considered as significantly differentially expressed. KEGG pathway analysis revealed that ten pathways were significantly enriched; the top two among them were protein processing in endoplasmic reticulum and MAPK signaling pathways. These results suggest that thermal stress triggered a complex response in Holstein calves and the animals adjusted their physiological and metabolic processes to survive. Many of the genes identified in this study have not been previously reported to be involved in thermal stress response. The results of this study extend our understanding of the animal's response to thermal stress and some of the identified genes may prove useful in the efforts to breed Holstein cattle with superior thermotolerance, which might help in minimizing production loss due to thermal stress.
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Affiliation(s)
- Krishnamoorthy Srikanth
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea
| | - Eunjin Lee
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea
| | - Anam Kwan
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea
| | - Youngjo Lim
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea
| | - Junyep Lee
- Environmental Science Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea
| | - Gulwon Jang
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea
| | - Hoyoung Chung
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, 1500, K & P road, Iseo, Wanju, JB, 55365, South Korea.
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Derbyshire MC, Michaelson L, Parker J, Kelly S, Thacker U, Powers SJ, Bailey A, Hammond-Kosack K, Courbot M, Rudd J. Analysis of cytochrome b(5) reductase-mediated metabolism in the phytopathogenic fungus Zymoseptoria tritici reveals novel functionalities implicated in virulence. Fungal Genet Biol 2015; 82:69-84. [PMID: 26074495 PMCID: PMC4557397 DOI: 10.1016/j.fgb.2015.05.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 12/15/2022]
Abstract
Septoria tritici blotch (STB) caused by the Ascomycete fungus Zymoseptoria tritici is one of the most economically damaging diseases of wheat worldwide. Z. tritici is currently a major target for agricultural fungicides, especially in temperate regions where it is most prevalent. Many fungicides target electron transfer enzymes because these are often important for cell function. Therefore characterisation of genes encoding such enzymes may be important for the development of novel disease intervention strategies. Microsomal cytochrome b5 reductases (CBRs) are an important family of electron transfer proteins which in eukaryotes are involved in the biosynthesis of fatty acids and complex lipids including sphingolipids and sterols. Unlike the model yeast Saccharomyces cerevisiae which possesses only one microsomal CBR, the fully sequenced genome of Z. tritici bears three possible microsomal CBRs. RNA sequencing analysis revealed that ZtCBR1 is the most highly expressed of these genes under all in vitro and in planta conditions tested, therefore ΔZtCBR1 mutant strains were generated through targeted gene disruption. These strains exhibited delayed disease symptoms on wheat leaves and severely limited asexual sporulation. ΔZtCBR1 strains also exhibited aberrant spore morphology and hyphal growth in vitro. These defects coincided with alterations in fatty acid, sphingolipid and sterol biosynthesis observed through GC-MS and HPLC analyses. Data is presented which suggests that Z. tritici may use ZtCBR1 as an additional electron donor for key steps in ergosterol biosynthesis, one of which is targeted by azole fungicides. Our study reports the first functional characterisation of CBR gene family members in a plant pathogenic filamentous fungus. This also represents the first direct observation of CBR functional ablation impacting upon fungal sterol biosynthesis.
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Affiliation(s)
- Mark C Derbyshire
- Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK.
| | - Louise Michaelson
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Josie Parker
- Centre for Cytochrome P450 Diversity, Institute of Life Science, College of Medicine, Swansea University Singleton Park, Swansea SA2 8PP, Wales, UK
| | - Steven Kelly
- Centre for Cytochrome P450 Diversity, Institute of Life Science, College of Medicine, Swansea University Singleton Park, Swansea SA2 8PP, Wales, UK
| | | | - Stephen J Powers
- Department of Computational and Systems Biology, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Andy Bailey
- Bristol University, Senate House, Tyndall Avenue, Bristol BS8 1TH, UK
| | - Kim Hammond-Kosack
- Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Mikael Courbot
- Syngenta, Syngenta AG, Schaffhauserstrasse, CH-4332 Stein, Switzerland
| | - Jason Rudd
- Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK.
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20
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Tan WH, Popel AS, Mac Gabhann F. Computational model of VEGFR2 pathway to ERK activation and modulation through receptor trafficking. Cell Signal 2013; 25:2496-510. [PMID: 23993967 DOI: 10.1016/j.cellsig.2013.08.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 08/24/2013] [Indexed: 01/09/2023]
Abstract
Vascular Endothelial Growth Factor (VEGF) signal transduction is central to angiogenesis in development and in pathological conditions such as cancer, retinopathy and ischemic diseases. We constructed and validated a computational model of VEGFR2 trafficking and signaling, to study the role of receptor trafficking kinetics in modulating ERK phosphorylation in VEGF-stimulated endothelial cells. Trafficking parameters were optimized and validated against four previously published in vitro experiments. Based on these parameters, model simulations demonstrated interesting behaviors that may be highly relevant to understanding VEGF signaling in endothelial cells. First, at moderate VEGF doses, VEGFR2 phosphorylation and ERK phosphorylation are related in a log-linear fashion, with a stable duration of ERK activation; but with higher VEGF stimulation, phosphoERK becomes saturated, and its duration increases. Second, a large endosomal fraction of VEGFR2 makes the ERK activation reaction network less sensitive to perturbations in VEGF dosage. Third, extracellular-matrix-bound VEGF binds and activates VEGFR2, but by internalizing at a slower rate, matrix-bound VEGF-induced intracellular ERK phosphorylation is predicted to be greater in magnitude and more sustained, in agreement with experimental evidence. Fourth, different endothelial cell types appear to have different trafficking rates, which result in different levels of endosomal receptor localization and different ERK response profiles.
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Affiliation(s)
- Wan Hua Tan
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, 720 Rutland Ave., Baltimore, MD 21205, USA
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Zhang X, Hao L, Meng L, Liu M, Zhao L, Hu F, Ding C, Wang Y, He B, Pan Y, Fang W, Chen J, Hu S, Jia M. Digital gene expression tag profiling analysis of the gene expression patterns regulating the early stage of mouse spermatogenesis. PLoS One 2013; 8:e58680. [PMID: 23554914 PMCID: PMC3598852 DOI: 10.1371/journal.pone.0058680] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 02/06/2013] [Indexed: 12/30/2022] Open
Abstract
Detailed characterization of the gene expression patterns in spermatogonia and primary spermatocytes is critical to understand the processes which occur prior to meiosis during normal spermatogenesis. The genome-wide expression profiles of mouse type B spermatogonia and primary spermatocytes were investigated using the Solexa/Illumina digital gene expression (DGE) system, a tag based high-throughput transcriptome sequencing method, and the developmental processes which occur during early spermatogenesis were systematically analyzed. Gene expression patterns vary significantly between mouse type B spermatogonia and primary spermatocytes. The functional analysis revealed that genes related to junction assembly, regulation of the actin cytoskeleton and pluripotency were most significantly differently expressed. Pathway analysis indicated that the Wnt non-canonical signaling pathway played a central role and interacted with the actin filament organization pathway during the development of spermatogonia. This study provides a foundation for further analysis of the gene expression patterns and signaling pathways which regulate the molecular mechanisms of early spermatogenesis.
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Affiliation(s)
- Xiujun Zhang
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
- Department of Reproductive Endocrinology, National Research Institute for Family Planning, Beijing, China
| | - Lili Hao
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Lijun Meng
- Department of Environment and Chemical Engineering, Tangshan College, Tangshan, Hebei, China
| | - Meiling Liu
- Department of Reproductive Endocrinology, National Research Institute for Family Planning, Beijing, China
| | - Lina Zhao
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Fen Hu
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Cunbao Ding
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Yang Wang
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Baoling He
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Yuxin Pan
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Wei Fang
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Jing Chen
- College of Life Sciences, Hebei United University, Tangshan, Hebei, China
| | - Songnian Hu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
- * E-mail: (SH); (MJ)
| | - Mengchun Jia
- Department of Reproductive Endocrinology, National Research Institute for Family Planning, Beijing, China
- * E-mail: (SH); (MJ)
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Pereira MF, Martino T, Dalmau SR, Paes MC, Barja-Fidalgo C, Albano RM, Coelho MGP, Sabino KCDC. Terpenic fraction of Pterodon pubescens inhibits nuclear factor kappa B and extracellular signal-regulated protein kinase 1/2 activation and deregulates gene expression in leukemia cells. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012. [PMID: 23181557 PMCID: PMC3538048 DOI: 10.1186/1472-6882-12-231] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Background Plant derived compounds have been shown to be important sources of several anti-cancer agents. As cell cycle deregulation and tumor growth are intimately linked, the discovery of new substances targeting events in this biochemical pathway would be of great value. The anti-leukemic effect of an ethanolic extract of Pterodon pubescens seeds (EEPp) has been previously demonstrated and now we show that a terpenic subfraction (SF5) of EEPp containing farnesol, geranylgeraniol and vouacapan derivatives induces apoptosis in the human chronic myelogenous leukemia cell line K562. This work addresses SF5’s antiproliferative mechanisms in these cells since they are still unclear. Methods DNA synthesis in K562 cells was assessed by [3H]-methyl-thymidine incorporation and cell cycle status by flow cytometry. The expression of cyclins D1 and E2, of the cell cycle inhibitor p21 and of the proto-oncogene c-myc was evaluated by semi-quantitative RT-PCR. Extracellular-signal-regulated kinases (ERK) 1/2 and nuclear factor kappa B (NF-κB) activation was evaluated by western blotting. Results In K562 cells, SF5 treatment induced a higher inhibition of DNA synthesis and cell growth than the original EEPp hexanic fraction from which SF5 originated, and also arrested the cell cycle in G1. Exposure of these cells to SF5 led to a decrease in cyclin E2 and c-myc expression while p21 mRNA levels were increased. Furthermore, SF5 inhibited the activation of mitogen-activated protein kinase (MAPK) ERK 1/2 and NF-κB. Conclusions This work suggests that the anti-leukemic action of SF5 is linked to the inhibition of ERKs, NF-κB and c-myc signaling pathways resulting in reduced cyclin E2 mRNA expression and cell cycle arrest in the G1 phase.
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Yu L, Nie J, Cao C, Jin Y, Yan M, Wang F, Liu J, Xiao Y, Liang Y, Zhang W. Phosphatidic acid mediates salt stress response by regulation of MPK6 in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2010; 188:762-73. [PMID: 20796215 DOI: 10.1111/j.1469-8137.2010.03422.x] [Citation(s) in RCA: 289] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
• Phospholipase D (PLD) hydrolyzes phospholipids to produce phosphatidic acid (PA) and a head group, and is involved in the response to various environmental stresses, including salinity. Here, we determined the roles of PLDα and PA in the mediation of salt (NaCl)-stress signaling through the regulation of mitogen-activated protein kinase (MAPK or MPK) in Arabidopsis thaliana. • NaCl-induced changes in the content and composition of PA were quantitatively profiled by electrospray ionization-tandem mass spectrometry (ESI-MS/MS). A specific PA species (a MAPK 16:0-18:2 PA), which was increased in abundance by exposure to NaCl, bound to a MPK6, according to filter binding and ELISA. The effect of PA on MPK6 activity was tested using in-gel analysis. • 16:0-18:2 PA stimulated the activity of MPK6 immunoprecipitated from Arabidopsis leaf extracts. Treatment with NaCl induced a transient activation of MPK6 in wild-type plant, but the activation was abolished in the pldα1 plant mutant. A plasma membrane Na(+)/H(+) antiporter (SOS1) was identified as a downstream target of MPK6. MPK6 phosphorylated the C-terminal fragment of SOS1. The MPK6 phosphorylation of SOS1 was stimulated by treatment with NaCl, as well as directly by PA. • These results suggest that PA plays a critical role in coupling MAPK cascades in response to salt stress.
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Affiliation(s)
- Lijuan Yu
- College of Life Sciences, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China
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Marcucci H, Paoletti L, Jackowski S, Banchio C. Phosphatidylcholine biosynthesis during neuronal differentiation and its role in cell fate determination. J Biol Chem 2010; 285:25382-93. [PMID: 20525991 DOI: 10.1074/jbc.m110.139477] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Neuronal differentiation is characterized by neuritogenesis and neurite outgrowth, processes that are dependent on membrane biosynthesis. Thus, the production of phosphatidylcholine (PtdCho), the major membrane phospholipid, should be stimulated during neuronal differentiation. We demonstrate that during retinoic acid (RA)-induced differentiation of Neuro-2a cells, PtdCho synthesis was promoted by an ordered and sequential activation of choline kinase alpha (CK(alpha)) and choline cytidylyltransferase alpha (CCT(alpha)). Early after RA stimulation, the increase in PtdCho synthesis is mainly governed by the biochemical activation of CCT(alpha). Later, the transcription of CK(alpha)- and CCT(alpha)-encoding genes was induced. Both PtdCho biosynthesis and neuronal differentiation are dependent on ERK activation. A novel mechanism is proposed by which PtdCho biosynthesis is coordinated during neuronal differentiation. Enforced expression of either CK(alpha) or CCTalpha increased the rate of synthesis and the amount of PtdCho, and these cells initiated differentiation without RA stimulation, as evidenced by cell morphology and the expression of genes associated with neuritogenesis. The differentiation resulting from enforced expression of CCT(alpha) or CK(alpha) was dependent on persistent ERK activation. These results indicate that elevated PtdCho synthesis could mimic the RA signals and thus determine neuronal cell fate. Moreover, they could explain the key role that PtdCho plays during neuronal regeneration.
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Affiliation(s)
- Hebe Marcucci
- Departamento de Ciencias Biológicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
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Chamberlain MD, Oberg JC, Furber LA, Poland SF, Hawrysh AD, Knafelc SM, McBride HM, Anderson DH. Deregulation of Rab5 and Rab4 proteins in p85R274A-expressing cells alters PDGFR trafficking. Cell Signal 2010; 22:1562-75. [PMID: 20570729 DOI: 10.1016/j.cellsig.2010.05.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 05/27/2010] [Accepted: 05/30/2010] [Indexed: 01/30/2023]
Abstract
Activated receptor tyrosine kinases recruit many signaling proteins to activate downstream cell proliferation and survival pathways, including phosphatidylinositol 3-kinase (PI3K) consisting of a p85 regulatory protein and a p110 catalytic protein. We have recently shown the p85alpha protein also has in vitro GTPase activating protein (GAP) activity towards Rab5 and Rab4, small GTPases that regulate vesicle trafficking events for activated receptors. Expression of a GAP-defective mutant, p85R274A, resulted in sustained levels of activated platelet-derived growth factor receptors (PDGFRs) and enhanced downstream signaling. In this report we have characterized Rab5- and Rab4-mediated PDGFR trafficking in cells expressing wild type p85 and GAP-defective mutant p85R274A. Wild type p85 overexpressing cells had slower PDGFR trafficking consistent with enhanced GAP activity deactivating Rab5 and Rab4 to block their vesicle trafficking functions. Mutant p85R274A expression increased the internalization rate of PDGFRs, a Rab5-dependent process, without preventing PDGFR ubiquitination. Immunofluorescence studies further demonstrated that p85R274A-expressing cells showed Rab5 accumulation at intracellular locations. Pull-down and FRAP (fluorescence recovery after photobleaching) experiments indicate this is likely membrane-associated Rab5-GTP, sustained due to decreased p85 GAP activity for the p85R274A mutant. These cells also had substantial amounts of activated PDGFRs in Rab4-positive recycling endosomes, a compartment that usually contains primarily deactivated/dephosphorylated receptors. Our results suggest that the PDGFR-associated GAP activity of p85 regulates both Rab5 and Rab4 functions in cells to influence the movement of activated PDGFR through endosomal compartments. Disruption of this regulation by p85R274A expression impacts PDGFR phosphorylation/dephosphorylation, degradation kinetics and downstream signaling by altering the time receptors spend in specific intracellular endosomal compartments. These results demonstrate that the p85alpha protein is an important regulator of Rab-mediated PDGFR trafficking, which significantly impacts receptor signaling and degradation.
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Affiliation(s)
- M Dean Chamberlain
- Cancer Research Unit, Research Division, Saskatchewan Cancer Agency, 20 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 4H4
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Yu J, Yin P, Liu F, Cheng G, Guo K, Lu A, Zhu X, Luan W, Xu J. Effect of heat stress on the porcine small intestine: a morphological and gene expression study. Comp Biochem Physiol A Mol Integr Physiol 2010; 156:119-28. [PMID: 20096800 DOI: 10.1016/j.cbpa.2010.01.008] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 01/13/2010] [Accepted: 01/14/2010] [Indexed: 12/13/2022]
Abstract
With the presence of global warming, the occurrence of extreme heat is becoming more common, especially during the summer, increasing pig susceptibility to severe heat stress. The aim of the current study was to investigate changes in morphology and gene expression in the pig small intestine in response to heat stress. Forty eight Chinese experimental mini pigs (Sus scrofa) were subjected to 40 degrees C for 5h each day for 10 successive days. Pigs were euthanized at 1, 3, 6, and 10 days after heat treatment and sections of the small intestine epithelial tissue were excised for morphological examination and microarray analyses. After heat treatment, the pig rectal temperature, the body surface temperature and serum cortisol levels were all significantly increased. The duodenum and jejunum displayed significant damage, most severe after 3 days of treatment. Microarray analysis found 93 genes to be up-regulated and 110 genes to be down-regulated in response to heat stress. Subsequent bioinformatic analysis (including gene ontology and KEGG pathway analysis) revealed the genes altered in response to heat stress related to unfolded protein, regulation of translation initiation, regulation of cell proliferation, cell migration and antioxidant regulation. Heat stress caused significant damage to the pig small intestine and altered gene expression in the pig jejunum. The results of the bioinformatic analysis from the present study will be beneficial to further investigate the underlying mechanisms involved in heat stress-induced damage in the pig small intestine.
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Affiliation(s)
- Jin Yu
- Department of Animal Science and Technology, Beijing University of Agriculture, Beijing, PR China
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Abstract
Owing to its favorable properties, such as low viscosity and high diffusivity, a supercritical fluid can be used as the mobile phase in chromatography. Supercritical fluid chromatography (SFC) can provide high-speed and high-resolution separation. Since supercritical carbon dioxide (SCCO2), which is generally used as the mobile phase in SFC, is automatically emitted at room temperature, SFC is most commonly used as a preparative method. However, SFC can also be used to perform high-precision biomolecular analysis, especially for hydrophobic metabolites, because of the low polarity of SCCO2. The use of a mass spectrometer with SFC can widen the scope of application of SFC to bioanalysis. In this review, we summarize practical application of SFC as a tool for the analysis of metabolites in real biological samples.
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Hu J, Troglio F, Mukhopadhyay A, Everingham S, Kwok E, Scita G, Craig AWB. F-BAR-containing adaptor CIP4 localizes to early endosomes and regulates Epidermal Growth Factor Receptor trafficking and downregulation. Cell Signal 2009; 21:1686-97. [PMID: 19632321 DOI: 10.1016/j.cellsig.2009.07.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 07/08/2009] [Accepted: 07/16/2009] [Indexed: 12/12/2022]
Abstract
Cdc42-Interacting Protein-4 (CIP4) family adaptors have been implicated in promoting Epidermal Growth Factor Receptor (EGFR) internalization, however, their unique or overlapping functions remain unclear. Here, we show that although CIP4 was not required for early events in clathrin-mediated endocytosis of EGFR, CIP4 localizes to vesicles containing EGFR and Rab5. Furthermore, expression of constitutively active Rab5 led to accumulation of CIP4 and the related adaptor Toca-1 in giant endosomes. Using a mutagenesis approach, we show that localization of CIP4 to endosomes is mediated in part via the curved phosphoinositide-binding face of the CIP4 F-BAR domain. Downregulation of CIP4 in A431 epidermoid carcinoma cells by RNA interference led to elevated EGFR levels, compared to control cells. Although surface expression of EGFR was not affected by CIP4 silencing, EGF-induced transit of EGFR from EEA1-positive endosomes to lysosomes was reduced compared to control cells. This correlated with more robust activation of ERK kinase and entry to S phase in CIP4-depleted A431 cells, compared to control cells. The combined silencing of CIP4 and Toca-1 was more effective in driving cells into S phase, suggesting a partial redundancy in their functions. Overall, our results implicate CIP4 and Toca-1 in regulating late events in EGFR trafficking from endosomes that serves to limit sustained ERK activation within the endosomal compartment.
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Affiliation(s)
- Jinghui Hu
- Queen's University Cancer Research Institute, Division of Cancer Biology & Genetics and Department of Biochemistry, Queen's University, Kingston, Ontario, Canada
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Haigh CL, Lewis VA, Vella LJ, Masters CL, Hill AF, Lawson VA, Collins SJ. PrPC-related signal transduction is influenced by copper, membrane integrity and the alpha cleavage site. Cell Res 2009; 19:1062-78. [PMID: 19597535 DOI: 10.1038/cr.2009.86] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Differential distribution of both IL-12Rbeta chains in the plasma membrane of human T cells. J Membr Biol 2008; 227:1-12. [PMID: 19067026 DOI: 10.1007/s00232-008-9127-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 09/05/2008] [Indexed: 10/21/2022]
Abstract
IL-12 is a cytokine that stimulates the expression of CD26, a T cell- and raft-associated ectopeptidase. IL-12 also enhances the interaction between CD26 and CD45RO, which removes the phosphatase CD45RO from raft microdomains. Since Janus kinases are known CD45 substrates, our hypothesis was that this relocation of CD45RO in nonraft areas of the membrane could be important to switch off the signaling via cytokine receptors, e.g., the IL-12 receptor (IL-12R). Accordingly, both IL-12R and CD45RO should be equally positioned in the cell membrane upon IL-12R ligation. However, there were no data available on the membrane distribution of IL-12R on human T cells. Working with phytohemagglutinin (PHA) lymphoblasts, we tried to fill that gap. The high-affinity IL-12R is made of two chains: IL-12Rbeta1 and IL-12Rbeta2. Using flow cytometry, Western blot and confocal microscopy, we obtained data suggesting that IL-12Rbeta1 is mainly associated to phospholipid-rich membrane areas, a location even enhanced upon IL-12 incubation of PHA blasts. Instead, IL-12Rbeta2 is found more segregated into membrane rafts, which could explain why two IL-12-triggered events, T-cell proliferation and ERK1/2 activation, are both methyl-beta-cyclodextrin-sensitive events. Ligation of IL-12R with IL-12 seems to induce a partial enrichment of IL-12Rbeta2 in phospholipid-rich areas, where according to our data IL-12Rbeta1 is already present. Therefore, although new data will be required, the present results support the initial hypothesis.
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Zurawski DV, Mumy KL, Faherty CS, McCormick BA, Maurelli AT. Shigella flexneri type III secretion system effectors OspB and OspF target the nucleus to downregulate the host inflammatory response via interactions with retinoblastoma protein. Mol Microbiol 2008; 71:350-68. [PMID: 19017275 DOI: 10.1111/j.1365-2958.2008.06524.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OspF, OspG and IpaH(9.8) are type III secretion system (T3SS) effectors of Shigella flexneri that downregulate the host innate immune response. OspF modifies mitogen-activated protein kinase pathways and polymorphonuclear leucocyte transepithelial migration associated with Shigella invasion. OspF also localizes in the nucleus to mediate chromatin remodelling, resulting in reduced transcription of inflammatory cytokines. We now report that OspB can be added to the set of S. flexneri T3SS effectors required to modulate the innate immune response. T84 cells infected with a Delta ospB mutant resulted in reduced polymorphonuclear leucocyte transepithelial migration and mitogen-activated protein kinase signalling. Tagged versions of OspB localized with endosomes and the nucleus. Further, T84 cells infected with the Delta ospB mutant showed increased levels of secreted IL-8 compared with wild-type infected cells. Both GST-OspB and GST-OspF coprecipitated retinoblastoma protein from host cell lysates. Because Delta ospB and Delta ospF mutants share similar phenotypes, and OspB and OspF share a host binding partner, we propose that OspB and OspF facilitate the remodelling of chromatin via interactions with retinoblastoma protein, resulting in diminished inflammatory cytokine production. The requirement of multiple T3SS effectors to modulate the innate immune response correlates to the complexity of the human immune system.
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Affiliation(s)
- Daniel V Zurawski
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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Inactivation of rho GTPases by statins attenuates anthrax lethal toxin activity. Infect Immun 2008; 77:348-59. [PMID: 18936176 DOI: 10.1128/iai.01005-08] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Anthrax lethal factor (LF), secreted by Bacillus anthracis, interacts with protective antigen to form a bipartite toxin (lethal toxin [LT]) that exerts pleiotropic biological effects resulting in subversion of the innate immune response. Although the mitogen-activated protein kinase kinases (MKKs) are the major intracellular protein targets of LF, the pathology induced by LT is not well understood. The statin family of HMG-coenzyme A reductase inhibitors have potent anti-inflammatory effects independent of their cholesterol-lowering properties, which have been attributed to modulation of Rho family GTPase activity. The Rho GTPases regulate vesicular trafficking, cytoskeletal dynamics, and cell survival and proliferation. We hypothesized that disruption of Rho GTPase function by statins might alter LT action. We show here that statins delay LT-induced death and MKK cleavage in RAW macrophages and that statin-mediated effects on LT action are attributable to disruption of Rho GTPases. The Rho GTPase-inactivating toxin, toxin B, did not significantly affect LT binding or internalization, suggesting that the Rho GTPases regulate trafficking and/or localization of LT once internalized. The use of drugs capable of inhibiting Rho GTPase activity, such as statins, may provide a means to attenuate intoxication during B. anthracis infection.
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Ben-Othman R, Guizani-Tabbane L, Dellagi K. Leishmania initially activates but subsequently down-regulates intracellular mitogen-activated protein kinases and nuclear factor-κB signaling in macrophages. Mol Immunol 2008; 45:3222-9. [DOI: 10.1016/j.molimm.2008.02.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 02/20/2008] [Accepted: 02/26/2008] [Indexed: 11/27/2022]
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Chamberlain MD, Chan T, Oberg JC, Hawrysh AD, James KM, Saxena A, Xiang J, Anderson DH. Disrupted RabGAP function of the p85 subunit of phosphatidylinositol 3-kinase results in cell transformation. J Biol Chem 2008; 283:15861-8. [PMID: 18387942 DOI: 10.1074/jbc.m800941200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Rab proteins regulate vesicle fusion events during the endocytosis, recycling, and degradation of activated receptor tyrosine kinases. The p85alpha subunit of phosphatidylinositol 3-kinase has GTPase-activating protein activity toward Rab5 and Rab4, an activity severely reduced by a single point mutation (p85-R274A). Expression of p85-R274A resulted in increased platelet-derived growth factor receptor (PDGFR) activation and downstream signaling (Akt and MAPK) and in decreased PDGFR degradation. We now report that the biological consequences of p85-R274A expression cause cellular transformation as determined by the following: aberrant morphological phenotype, loss of contact inhibition, growth in soft agar, and tumor formation in nude mice. Immunohistochemistry shows that the tumors contain activated PDGFR and high levels of activated Akt. Coexpression of a dominant negative Rab5-S34N mutant attenuated these transformed properties. Our results demonstrate that disruption of the RabGAP function of p85alpha due to a single point mutation (R274A) is sufficient to cause cellular transformation via a phosphatidylinositol 3-kinase-independent mechanism partially reversed by Rab5-S34N expression. This critical new role for p85 in the regulation of Rab function suggests a novel role for p85 in controlling receptor signaling and trafficking through its effects on Rab GTPases.
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Affiliation(s)
- M Dean Chamberlain
- Cancer Research Unit, Health Research Division, Saskatchewan Cancer Agency, Saskatoon, Saskatchewan S7N 4H4, Canada
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Vergés M. Retromer: multipurpose sorting and specialization in polarized transport. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 271:153-98. [PMID: 19081543 DOI: 10.1016/s1937-6448(08)01204-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Retromer is an evolutionary conserved protein complex required for endosome-to-Golgi retrieval of lysosomal hydrolases' receptors. A dimer of two sorting nexins-typically, SNX1 and/or SNX2-deforms the membrane and thus cooperates with retromer to ensure cargo sorting. Research in various model organisms indicates that retromer participates in sorting of additional molecules whose proper transport has important repercussions in development and disease. The role of retromer as well as SNXs in endosomal protein (re)cycling and protein targeting to specialized plasma membrane domains in polarized cells adds further complexity and has implications in growth control, the establishment of developmental patterns, cell adhesion, and migration. This chapter will discuss the functions of retromer described in various model systems and will focus on relevant aspects in polarized transport.
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Affiliation(s)
- Marcel Vergés
- Laboratory of Epithelial Cell Biology, Centro de Investigación Príncipe Felipe, C/E.P. Avda. Autopista del Saler, Valencia, Spain
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Where and how do anthrax toxins exit endosomes to intoxicate host cells? Trends Microbiol 2007; 15:477-82. [PMID: 17983750 DOI: 10.1016/j.tim.2007.10.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 08/06/2007] [Accepted: 10/25/2007] [Indexed: 01/19/2023]
Abstract
The role of Bacillus anthracis virulence factors in its pathogenesis has been subjected to intense investigation with the aim of finding novel preventive and therapeutic protocols. Toxins that are endocytosed and act in the cytosol of host cells have a central role in B. anthracis infection. Understanding of anthrax toxin cell entry has increased during the past few years and a composite picture is emerging. Nevertheless, unanswered and controversial questions remain, particularly concerning the site and mode of anthrax toxin cell entry, the role of anthrax toxin receptors in the process and the possible involvement of cytosolic chaperones, which might affect entry efficiency. Here, the current model of anthrax toxin cell entry, an alternative model and experimental approaches for clarifying unanswered questions will be discussed.
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Fogle KJ, Lyashchenko AK, Turbendian HK, Tibbs GR. HCN pacemaker channel activation is controlled by acidic lipids downstream of diacylglycerol kinase and phospholipase A2. J Neurosci 2007; 27:2802-14. [PMID: 17360902 PMCID: PMC6672581 DOI: 10.1523/jneurosci.4376-06.2007] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Hyperpolarization-activated pacemaker currents (I(H)) contribute to the subthreshold properties of excitable cells and thereby influence behaviors such as synaptic integration and the appearance and frequency of intrinsic rhythmic activity. Accordingly, modulation of I(H) contributes to cellular plasticity. Although I(H) activation is regulated by a plethora of neurotransmitters, including some that act via phospholipase C (PLC), the only second messengers known to alter I(H) voltage dependence are cAMP, internal protons (H+(I)s), and phosphatidylinositol-4,5-phosphate. Here, we show that 4beta-phorbol-12-myristate-13-acetate (4betaPMA), a stereoselective C-1 diacylglycerol-binding site agonist, enhances voltage-dependent opening of wild-type and cAMP/H+(I)-uncoupled hyperpolarization-activated, cyclic nucleotide-regulated (HCN) channels, but does not alter gating of the plant hyperpolarization-activated channel, KAT1. Pharmacological analysis indicates that 4betaPMA exerts its effects on HCN gating via sequential activation of PKC and diacylglycerol kinase (DGK) coupled with upregulation of MAPK (mitogen-activated protein kinase) and phospholipase A2 (PLA2), but its action is independent of phosphoinositide kinase 3 (PI3K) and PI4K. Demonstration that both phosphatidic acid and arachidonic acid (AA) directly facilitate HCN gating suggests that these metabolites may serve as the messengers downstream of DGK and PLA2, respectively. 4BetaPMA-mediated suppression of the maximal HCN current likely arises from channel interaction with AA coupled with an enhanced membrane retrieval triggered by the same pathways that modulate channel gating. These results indicate that regulation of excitable cell behavior by neurotransmitter-mediated modulation of I(H) may be exerted via changes in three signaling lipids in addition to the allosteric actions of cAMP and H+(I)s.
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Affiliation(s)
| | | | | | - Gareth R. Tibbs
- the Departments of Anesthesiology and
- Pharmacology, Columbia University, New York, New York 10032
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Bliss SP, Navratil AM, Breed M, Skinner DC, Clay CM, Roberson MS. Signaling complexes associated with the type I gonadotropin-releasing hormone (GnRH) receptor: colocalization of extracellularly regulated kinase 2 and GnRH receptor within membrane rafts. Mol Endocrinol 2006; 21:538-49. [PMID: 17068198 DOI: 10.1210/me.2006-0289] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Our previous work demonstrated that the type I GnRH receptor (GnRHR) resides exclusively and constitutively within membrane rafts in alphaT3-1 gonadotropes and that this association was necessary for the ability of the receptor to couple to the ERK signaling pathway. G(alphaq), c-raf, and calmodulin have also been shown to reside in this compartment, implicating a raft-associated multiprotein signaling complex as a functional link between the GnRHR and ERK signaling. In the studies reported here, we used subcellular fractionation and coimmunoprecipitation to analyze the behavior of ERKs with respect to this putative signaling platform. ERK 2 associated partially and constitutively with low-density membranes both in alphaT3-1 cells and in whole mouse pituitary. Cholesterol depletion of alphaT3-1 cells reversibly blocked the association of both the GnRHR and ERKs with low-density membranes and uncoupled the ability of GnRH to activate ERK. Analysis of the kinetics of recovery of ERK inducibility after cholesterol normalization supported the conclusion that reestablishment of the association of the GnRHR and ERKs with the membrane raft compartment was not sufficient for reconstitution of signaling activity. In alphaT3-1 cells, the GnRHR and ERK2 coimmunoprecipitated from low-density membrane fractions prepared either in the presence or absence of detergent. The GnRHR also partitioned into low-density, detergent-resistant membrane fractions in mouse pituitary and coimmunoprecipitated with ERK2 from these fractions. Collectively, these data support a model in which coupling of the GnRHR to the ERK pathway in gonadotropes involves the assembly of a multiprotein signaling complex in association with specialized microdomains of the plasma membrane.
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Affiliation(s)
- Stuart P Bliss
- Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853, USA
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