Molecular cell biology research communications : MCBRC最新文献_第2页

Role of the Oncogenic Raf-1 in Orchestration of Discrete Nuclear Factor-κB-Activating Pathways 致癌性Raf-1在离散核因子-κ b激活通路中的作用

Molecular cell biology research communications : MCBRC Pub Date : 2001-11-01 DOI: 10.1006/mcbr.2001.0304

Qingyan Liu , Jianguo Fan , Martin McMahon , Alfred M. Prince , Pei Zhang

{"title":"Role of the Oncogenic Raf-1 in Orchestration of Discrete Nuclear Factor-κB-Activating Pathways","authors":"Qingyan Liu , Jianguo Fan , Martin McMahon , Alfred M. Prince , Pei Zhang","doi":"10.1006/mcbr.2001.0304","DOIUrl":"10.1006/mcbr.2001.0304","url":null,"abstract":"<div><p>Raf-1, a key kinase in the Ras signaling pathway, plays critical roles in cell differentiation, proliferation, and tumorigenesis. However, knowledge of the Raf-1 in inflammation is limited. Using an inducible oncogenic Raf-1, we show that the Raf-1 orchestrates the discrete NF-κB activating pathways. While the Raf-1 activation induces a modest IκB degradation by enhancing the basal IκB kinase activity, it contradictorily suppresses the proinflammatory cytokine inducible IκB kinase complex, leading to an inhibition of TNF-α- and IL-1β-induced NF-κB activation. Despite considerable degrees of overlap, LPS signaling is not affected by Raf-1. By either conditionally reducing Raf-1 activity or completely disrupting the Raf-1 signaling by PD98059, a specific inhibitor of MEK1, the otherwise inhibited cytokine responses can be restored. Moreover, when the activity of Raf-1 is up-regulated during the cell cycle progression from the G<sub>0</sub> phase to the late G<sub>1</sub> phase, the enhanced Raf-1 activity suffices to shift the TNF-α response from the sensitive to the insensitive state. Together, these studies elucidate a mechanism by which signaling outputs are shaped by the intracellular Raf-1, thus explaining the “cellular context”-dependent cytokine response.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 6","pages":"Pages 381-389"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0304","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88250627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Phosphorylation of Histones Triggers DNA Fragmentation in Thymocyte Undergoing Apoptosis Induced by Protein Phosphatase Inhibitors 蛋白磷酸酶抑制剂诱导胸腺细胞凋亡时组蛋白磷酸化触发DNA断裂

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0291

Riyo Enomoto , Rina Koyamazaki , Yumi Maruta , Motoko Tanaka , Kazuhiro Takuma , Koichi Mori , Eibai Lee

{"title":"Phosphorylation of Histones Triggers DNA Fragmentation in Thymocyte Undergoing Apoptosis Induced by Protein Phosphatase Inhibitors","authors":"Riyo Enomoto , Rina Koyamazaki , Yumi Maruta , Motoko Tanaka , Kazuhiro Takuma , Koichi Mori , Eibai Lee","doi":"10.1006/mcbr.2001.0291","DOIUrl":"10.1006/mcbr.2001.0291","url":null,"abstract":"<div><p>The treatment of thymocytes with protein phosphatase inhibitors such as calyculin A and okadaic acid resulted in apoptosis with a concomitant increase in phosphorylation of nuclear proteins. The phosphorylated protein in the thymocyte nuclei induced by protein phosphatase inhibitors was identified as histones by the use of two-dimensional polyacrylamide gel electrophoresis. These compounds accelerated the phosphorylation of histone H2A, H3, and H1. On the other hand, little phosphorylation of H2B and H4 by these compounds was observed. The effect of these compounds on the level of nuclear histones was also examined using high-performance capillary electrophoresis. No significant changes in the level of histones were seen in the nuclei of thymocytes treated with calyculin A and okadaic acid. Thus, the induction of thymocyte apoptosis is involved in the chemical modification of histones but not the change in their quantity. Moreover, the treatment of thymocytes with calyculin A increased the sensitivity toward endogenous DNase in the nuclei. These results suggest that phosphorylation of histones, especially H2A, H3, and H1, is an early step of triggering DNA fragmentation in thymocyte apoptosis.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 5","pages":"Pages 276-281"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0291","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82896676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15

A Mutation in the Yeast Mitochondrial Ribosomal Protein Rml2p Is Associated with a Defect in Catalase Gene Expression 酵母线粒体核糖体蛋白Rml2p突变与过氧化氢酶基因表达缺陷相关

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0294

Ruth A. Hagerman , Pamela J. Trotter

{"title":"A Mutation in the Yeast Mitochondrial Ribosomal Protein Rml2p Is Associated with a Defect in Catalase Gene Expression","authors":"Ruth A. Hagerman , Pamela J. Trotter","doi":"10.1006/mcbr.2001.0294","DOIUrl":"10.1006/mcbr.2001.0294","url":null,"abstract":"<div><p>Yeast strains containing a new temperature-sensitive allele of the <em>RML2</em> gene, encoding a component of the large subunit of the mitochondrial ribosome, display normal growth on acetate, slowed growth on glycerol and an inability to grow on oleic acid. These cells, denoted <em>rml2(fat21),</em> have an apparent inability to induce peroxisomal function, as evidenced by a deficiency in oleic acid induction of beta-oxidation. However, the oleic acid regulation of genes encoding core enzymes of peroxisomal beta-oxidation is normal. In contrast, up-regulation of <em>CTA1</em> (catalase) mRNA expression and enzyme activity is interrupted. Upon comparison of the induction requirements of catalase and the genes of beta-oxidation, we hypothesized that the <em>rml2(fat21)</em> mutation alters the activity of the transcription factor Adr1p. In support of this hypothesis, over-expression of <em>ADR1</em> in <em>rml2(fat21)</em> cells restores <em>CTA1</em> induction. Several assays of mitochondria from <em>rml2(fat21)</em> strains suggest normal mitochondrial function. Thus, the modulation of Adr1p-associated gene regulation is not due to overt mitochondrial dysfunction.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 5","pages":"Pages 299-306"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0294","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79770844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Author Index for Volume 4, Number 5 第4卷第5号的作者索引

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0308

引用次数: 0

An Intramolecular Contact in Gα Transducin That Participates in Maintaining Its Intrinsic GDP Release Rate 参与维持其内在GDP释放速率的Gα转导蛋白分子内接触

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0293

Tarita O. Thomas , Hyunsu Bae , Martina Medkova , Heidi E. Hamm

{"title":"An Intramolecular Contact in Gα Transducin That Participates in Maintaining Its Intrinsic GDP Release Rate","authors":"Tarita O. Thomas , Hyunsu Bae , Martina Medkova , Heidi E. Hamm","doi":"10.1006/mcbr.2001.0293","DOIUrl":"https://doi.org/10.1006/mcbr.2001.0293","url":null,"abstract":"<div><p>Receptor mediated stimulation of the G protein-α subunit leads to exchange of GDP for GTP, activating the protein. Spontaneous GDP release from Gα can also lead to the active state, if GTP in solution binds the nucleotide binding pocket. The purpose of this study is to evaluate the molecular determinants for maintaining the spontaneous GDP release rates between two Gα subunits. Gα<sub>t</sub> has a low rate of nucleotide release, compared to Gα<sub>i1</sub>. Gα<sub>t/i1</sub> chimeras were used to explore the molecular basis for this behavior. The C-terminal α4-helix, the N-terminal 56 residues and the Switch I/II regions of Gα<sub>t</sub> were shown to affect the low spontaneous GDP release rate in Gα<sub>t</sub>. A specific molecular contact between Asp26 and Asn191 was found in Gα<sub>t</sub> that is not present in Gα<sub>i1</sub>. In two chimeras disrupting this interaction produced an increased spontaneous GDP release; restoring the contact present in Gα<sub>t</sub> into these chimeras decreased the GDP release rate by half as compared to the original chimeras. Similarly, introduction of this contact in wild-type Gα<sub>i1</sub> decreased the GDP release rate of Gα<sub>i1</sub> by half. Differences in GDP release rates may reflect physiological roles these proteins play in living systems.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 5","pages":"Pages 282-291"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0293","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136519812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Crosstalk between NF-κB-Activating and Apoptosis-Inducing Proteins of the TNF-Receptor Complex NF-κ b活化蛋白与tnf受体复合物诱导凋亡蛋白间的串扰

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0295

Karen Heyninck, Rudi Beyaert

引用次数: 79

The Chicken RelB Transcription Factor Has Transactivation Sequences and a Tissue-Specific Expression Pattern That Are Distinct from Mammalian RelB 鸡RelB转录因子具有不同于哺乳动物RelB的转录激活序列和组织特异性表达模式

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0290

Kathryn A. Piffat , Radmila Hrdličková , Jiri Nehyba , Toshio Ikeda , Andrew Liss , Sidong Huang , Saı̈d Sif , Thomas D. Gilmore , Henry R. Bose Jr.

{"title":"The Chicken RelB Transcription Factor Has Transactivation Sequences and a Tissue-Specific Expression Pattern That Are Distinct from Mammalian RelB","authors":"Kathryn A. Piffat , Radmila Hrdličková , Jiri Nehyba , Toshio Ikeda , Andrew Liss , Sidong Huang , Saı̈d Sif , Thomas D. Gilmore , Henry R. Bose Jr.","doi":"10.1006/mcbr.2001.0290","DOIUrl":"10.1006/mcbr.2001.0290","url":null,"abstract":"<div><p>Rel/NF-κB proteins are eukaryotic transcription factors that control the expression of genes involved in a large variety of cellular processes. Rel proteins share a highly conserved DNA-binding/dimerization domain called the Rel Homology (RH) domain. We have constructed and characterized a composite cDNA encoding most of the chicken RelB transcription factor. The predicted chicken RelB protein has a high degree of sequence similarity to other vertebrate RelB proteins within the RH domain, but is much less conserved outside this domain. Chicken RelB does not bind DNA as a homodimer, but forms DNA-binding heterodimers with NF-κB p50 or p52. Overexpressed chicken RelB localizes to the nucleus in chicken embryo fibroblasts, and the nonconserved C-terminal sequences of chicken RelB contain a transactivation domain that functions in chicken and mouse fibroblasts. Thus, chicken RelB has functional properties similar to other vertebrate RelB proteins. However, Western blotting of diverse chicken tissues indicates that chicken RelB is more widely expressed than mammalian RelB.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 5","pages":"Pages 266-275"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0290","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79805128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Participation of Intracellular Ca2+/Calmodulin and Protein Kinase(s) in the Pathway of Apoptosis Induced by a Drosophila Cell Death Gene, reaper 细胞内Ca2+/钙调蛋白和蛋白激酶(s)参与果蝇细胞死亡基因诱导的凋亡途径，reaper

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0297

Zheng-fu Piao, Kumiko Ui-Tei , Masatoshi Nagano, Yuhei Miyata

引用次数: 4

Cloning and Tissue-Specific Gene Expression Studies with Dlxin-1, a Newly Identified Transcriptional Activator 新发现的转录激活因子Dlxin-1的克隆及组织特异性基因表达研究

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0298

Anjali Shiras , Angana Sengupta, Varsha Shepal

{"title":"Cloning and Tissue-Specific Gene Expression Studies with Dlxin-1, a Newly Identified Transcriptional Activator","authors":"Anjali Shiras , Angana Sengupta, Varsha Shepal","doi":"10.1006/mcbr.2001.0298","DOIUrl":"10.1006/mcbr.2001.0298","url":null,"abstract":"<div><p>Dlxin-1, a unique member of the necdin/melanoma associated antigen gene (MAGE) family, is a novel protein that binds Dlxin-5 and regulates its transcriptional function. We have cloned the homology region between Dlxin-1 and necdin from mouse melanoma cells. Here we report the expression cloning, characterization, and detailed tissue-specific expression studies of Dlxin-1. A unique expression pattern of Dlxin-1 emerged from the work wherein strong expression of a 3.2-Kb transcript was observed in mouse brain and embryos. Amongst the representative established cell lines of different tumor categories studied the presence of transcript was detected only in sarcomas and neuroectodermal tumors. Characteristically, lymphomas, leukaemias, adenocarcinomas, and carcinomas did not express Dlxin-1. Also, we observed a growth suppression on ectopic expression of this cDNA possibly due to the close homology shared with necdin, a neuron-specific growth suppressor. The extensive homology of our Dlxin-1 clone to necdin makes it an attractive system to understand the importance of the necdin/MAGE family of molecules in cell cycle regulation.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 5","pages":"Pages 313-319"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0298","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80576359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Involvement of Conserved Hydrophobic Residues in the CTLD of Human Lectin-like Oxidized LDL Receptor in Ligand Binding 人凝集素样氧化LDL受体CTLD中保守疏水残基参与配体结合

Molecular cell biology research communications : MCBRC Pub Date : 2001-09-01 DOI: 10.1006/mcbr.2001.0296

Xiaohua Shi, Setsuko Ogawa, Toshio Otani, Sachiko Machida

{"title":"Involvement of Conserved Hydrophobic Residues in the CTLD of Human Lectin-like Oxidized LDL Receptor in Ligand Binding","authors":"Xiaohua Shi, Setsuko Ogawa, Toshio Otani, Sachiko Machida","doi":"10.1006/mcbr.2001.0296","DOIUrl":"10.1006/mcbr.2001.0296","url":null,"abstract":"<div><p>We previously identified the hydrophilic residues that are essential for ligand binding in the C-type lectin-like domain (CTLD) of human lectin-like oxidized LDL receptor (hLOX-1). To provide a more detailed understanding of ligand binding, we selected in the present study 13 conserved hydrophobic residues in the CTLD of hLOX-1 for mutagenesis analysis. The selected residues were replaced either by Ser (drastic mutation) or by size- and structure-based alternative hydrophobic residues (conserved mutation). Mutation targeted at F228, Y238, and G232 deprived hLOX-1 of ligand binding without alteration of protein expression and localization. In contrast, drastic mutation introduced into positions W203, W215, and W217 resulted in mislocalization, whereas conserved mutation at the same sites resulted in clones with similar cell surface localization and ligand binding to native hLOX-1. Our results indicate that F228, Y238, and G232 are essential for ligand binding, while W203, W215, W217, and L206 play a structural role.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"4 5","pages":"Pages 292-298"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2001.0296","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88507380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5