Molecular cell biology research communications : MCBRC最新文献_第9页

Repression of Transcription by HoxC11 upon Phorbol Ester Stimulation HoxC11在phobol酯刺激下的转录抑制

Molecular cell biology research communications : MCBRC Pub Date : 2000-06-01 DOI: 10.1006/mcbr.2000.0240

I.P. Sur , R. Toftgård

{"title":"Repression of Transcription by HoxC11 upon Phorbol Ester Stimulation","authors":"I.P. Sur , R. Toftgård","doi":"10.1006/mcbr.2000.0240","DOIUrl":"10.1006/mcbr.2000.0240","url":null,"abstract":"<div><p>Hox genes encode transcription factors with a conserved DNA-binding domain and exhibit similar DNA-binding preferences. The <em>in vivo</em> specificity required for their biological function is brought about by combinatorial interactions with other factors. Such interactions also modulate their activation state. Here we show that HoxC11 can either activate or repress transcription in a signal-specific manner. We report the isolation of <em>HoxC11</em> in a yeast one-hybrid screen for factors binding to a phorbol-ester, 12-<em>O</em>-tetradecanoylphorbol-13-acetate (TPA) response element (<em>VLTRE</em>), which is also a target for TPA-induced binding of Rel factors in gel-shift experiments. Although we detect no binding of <em>in vitro</em> translated HoxC11 to the TPA response element in EMSA, overexpression of HoxC11 in the HepG2 cell line leads to a complete block of TPA-induced transcription from a <em>VLTRE-luciferase</em> reporter. There is, however, no repression of the basal levels. The repression is furthermore not dependent on homeo-domain DNA binding. Our data suggest an interaction of HoxC11 with the basal-transcription machinery. We propose that HoxC11 is capable of mediating transcriptional activation or repression in a signal-specific manner and that its activation of the DNA target sequence in yeast might reflect <em>in vivo</em> recruitment to the promoter complex.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 6","pages":"Pages 367-373"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0240","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21862846","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: 2

Author Index for Volume 3, Number 5 第3卷第5号作者索引

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0234

引用次数: 0

The Generation of Localized Calcium Rises Mediated by Cell Adhesion Molecules and Their Role in Neuronal Growth Cone Motility 细胞粘附分子介导局部钙升高的产生及其在神经元生长锥运动中的作用

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0225

Dara J. Dunican, Patrick Doherty

{"title":"The Generation of Localized Calcium Rises Mediated by Cell Adhesion Molecules and Their Role in Neuronal Growth Cone Motility","authors":"Dara J. Dunican, Patrick Doherty","doi":"10.1006/mcbr.2000.0225","DOIUrl":"10.1006/mcbr.2000.0225","url":null,"abstract":"<div><p>Neurite growth and guidance depends on the transduction of extracellular guidance cues into motile responses by the sensory apparatus at the tip of the neurite, the growth cone. Contact of the growth cone with extracellular ligands leads to the cytoskeletal reorganisation required for changes in rate of motility and direction of outgrowth. Differential adhesion mediated by cell adhesion molecules and signal transduction pathways mediated by growth cone receptors were once seen as separate but cooperative events in controlling growth cone motility. However, recent findings suggest that cell adhesion molecules can activate novel signalling pathways in the growth cone by the recruitment of fibroblast growth factor receptors leading to neurite outgrowth. This Review focuses on work by various laboratories centering on the intracellular consequences of the cell adhesion molecule-mediated activation of the fibroblast growth factor receptor. These include activation of a lipase cascade including phospholipase C and diacylglycerol lipase and culminating in the release of arachidonic acid. This release of arachidonic acid is proposed to activate the transient opening of voltage dependent ion-channels leading to localised rises in growth Ca<sup>2+</sup>. Recent findings demonstrating this previously undetectable rise in Ca<sup>2+</sup> in the growth cone are discussed in light of the proposed roles and mechanisms of Ca<sup>2+</sup> in controlling neurite outgrowth. The Ca<sup>2+</sup> rises are thought to induce the activation of GAP43 and Ca<sup>2+</sup>/calmodulin-dependent kinase II, molecules implicated in the modulation of cytoskeletal remodelling. The evidence that this pathway may be involved in the guidance of retinal ganglion cells is evaluated.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 5","pages":"Pages 255-263"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0225","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21799874","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: 32

Phosphoinositide 3-Kinases and the Regulation of Vesicular Trafficking 磷酸肌肽3-激酶与水泡转运的调控

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0233

Jonathan M. Backer

引用次数: 0

Housekeeping Genes Commanded to Commit Suicide in CpG-Cleavage Commitment Upstream of Bcl-2 Inhibition in Caspase-Dependent and -Independent Pathways 在caspase依赖性和非依赖性途径中Bcl-2抑制上游的cpg切割过程中，管家基因被命令自杀

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0232

L. Qi, K.H. Sit

{"title":"Housekeeping Genes Commanded to Commit Suicide in CpG-Cleavage Commitment Upstream of Bcl-2 Inhibition in Caspase-Dependent and -Independent Pathways","authors":"L. Qi, K.H. Sit","doi":"10.1006/mcbr.2000.0232","DOIUrl":"10.1006/mcbr.2000.0232","url":null,"abstract":"<div><p>A CpG-specific commitment common to both caspase-dependent and -independent cell deaths implies critical gene activity from epigenetic modulation. Using a focused microarray (genechip) of 22 housekeeping genes, which have canonical CpG islands at 5′-promoter regions, here we show critical regulation of vital intermediary metabolism and cell structure that are common to both caspase-dependent fasL-mediated and caspase-independent etoposide-mediated cell deaths. Gene activity of at least twofold under or over control levels and common to both cell death pathways was considered to be significantly regulated in common. Seven genes controlling energy production in glycolysis, tricarboxylic acid cycle, and the respiratory electron transport chain were significantly downregulated in common. Energy depletion is lethal. Downregulated pyruvate dehydrogenase E1 gene, in addition, suggested primary metabolic acidification. Cell acidification is also lethal. Critical derangement of the cell structure was suggested by common downregulation of the basal histone gene H2A.X which is required for nucleosome assembly. Common upregulation of the α-tubulin gene suggested perturbation of vital microtubular dynamics. Gene-commanded cell suicide was suggested. We further show that a Bcl-2 overexpression of three- to fourfold above normal levels could not prevent the CpG-specific megabase DNA cleavages in the two cell death pathways, but abolished their low-molecular-weight 200-bp ladder cleavages. Together with incomplete suppression of the other apoptotic expressions, the Bcl-2 inhibition point appeared downstream from the CpG-cleavage commitment point.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 5","pages":"Pages 319-327"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0232","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21799800","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: 8

Multiple, Closely Spaced Alternative 5′ Exons in the DmCKIIβ Gene of Drosophila melanogaster 果蝇DmCKIIβ基因中多个紧密间隔的5 '外显子

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0223

Ashok P. Bidwai , Amit Saxena , Wenfan Zhao , Richard O. McCann , Claiborne V.C. Glover

{"title":"Multiple, Closely Spaced Alternative 5′ Exons in the DmCKIIβ Gene of Drosophila melanogaster","authors":"Ashok P. Bidwai , Amit Saxena , Wenfan Zhao , Richard O. McCann , Claiborne V.C. Glover","doi":"10.1006/mcbr.2000.0223","DOIUrl":"10.1006/mcbr.2000.0223","url":null,"abstract":"<div><p><em>Drosophila melanogaster</em> casein kinase II (CKII) is composed of catalytic α and regulatory β subunits. Using the two-hybrid system, we have isolated a number of cDNAs that are related to a previously published cDNA encoding the β subunit, but exhibit divergent 5′ sequences. To determine the source of this sequence variation, we have isolated the gene encoding the β subunit of CKII. The β gene contains five exons encompassing the complete open reading frame, as well as five alternative exons in the 5′ untranslated region (UTR). Only one 5′ UTR exon is contained in each cDNA, implying five distinct classes of transcript. In addition, the β gene contains at least two poly(A) addition signals which generate additional complexity at the 3′ end. The complex pattern of transcription may serve a role in the spatial and/or temporal expression of the β subunit since, with one exception, all transcripts encode the full-length β polypeptide. Phylogenetic comparison of the β genes of <em>Drosophila, C. elegans,</em> and mammals reveals three invariant introns as well as evidence of recent intron gain/loss.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 5","pages":"Pages 283-291"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0223","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21799795","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: 14

Telomere Dynamics in Cells with Introduced Telomerase: A Rapid Assay for Telomerase Activity on Telomeres 引入端粒酶的细胞端粒动力学:端粒酶活性的快速测定

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0229

Patricia A. McChesney, Dara L. Aisner, Bryan C. Frank, Woodring E. Wright, Jerry W. Shay

{"title":"Telomere Dynamics in Cells with Introduced Telomerase: A Rapid Assay for Telomerase Activity on Telomeres","authors":"Patricia A. McChesney, Dara L. Aisner, Bryan C. Frank, Woodring E. Wright, Jerry W. Shay","doi":"10.1006/mcbr.2000.0229","DOIUrl":"10.1006/mcbr.2000.0229","url":null,"abstract":"<div><p>Most immortal cell lines derived from human cancers or transformed <em>in vitro</em> maintain telomeres by endogenous expression of telomerase. In the present work, immortal cells that already express endogenous telomerase activity were induced to overexpress an exogenous telomerase (hTERT) and were analyzed for changes in telomere length. Introduction of hTERT into telomerase-positive immortal cell lines results in elevated telomerase activity as measured by the TRAP assay, leading to elongated telomeres in the cell lines tested. We explore possibilities for regulatory differences among the cell lines, including the level of overexpression of the catalytic subunit hTERT and the endogenous levels of telomere binding proteins. Reducing levels of hTERT expression with a construct containing an inefficient translation initiation sequence provided sufficient telomerase expression for maximal rates of telomere elongation. Overexpression of the hTERT alters the telomere length normally maintained in these cells and provides a very useful assay for the rapid analysis of telomerase activity on its native substrate, telomeres.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 5","pages":"Pages 312-318"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0229","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21799799","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: 16

Deletion Mutagenesis of the 5′ psbA2 Region in Synechocystis 6803: Identification of a Putative cis Element Involved in Photoregulation 胞囊藻6803 5 ' psbA2区域的缺失突变:一个推测参与光调控的顺式元件的鉴定

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0227

Jan Eriksson, Gaza F. Salih, Haile Ghebramedhin, Christer Jansson

{"title":"Deletion Mutagenesis of the 5′ psbA2 Region in Synechocystis 6803: Identification of a Putative cis Element Involved in Photoregulation","authors":"Jan Eriksson, Gaza F. Salih, Haile Ghebramedhin, Christer Jansson","doi":"10.1006/mcbr.2000.0227","DOIUrl":"10.1006/mcbr.2000.0227","url":null,"abstract":"<div><p>Three <em>Synechocystis</em> 6803 mutants, with deletions in the upstream region of the light-regulated <em>psbA2</em> gene, were constructed. All three mutants grew photoautotrophically but they were affected in <em>psbA2</em> expression. In one of the mutants, ΔU80, <em>psbA2</em> transcription levels were not suppressed under low light conditions and production of <em>psbA2</em> transcripts occurred also in darkness, in contrast to the situation in the control strain. Comparative sequence analyses of the mutants identified a hexanucleotide repeat as possible <em>cis</em> element in <em>psbA2</em> light regulation. Electrophoresis mobility shift assays showed that protein binding to the hexanucleotide repeat decreased with light intensity, consistent with a hypothesis that the repeat harbors a binding site for a repressor protein. Repeats similar to that in <em>psbA2</em> were found also in the upstream region of other light-regulated genes in <em>Synechocystsis</em> 6803. We refer to these hexanucleotide repeats as High Light Regulatory 1 (HLR1) sequences.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 5","pages":"Pages 292-298"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0227","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21799796","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: 60

Angiostatin Induces Mitotic Cell Death of Proliferating Endothelial Cells 血管抑制素诱导增殖内皮细胞有丝分裂细胞死亡

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0222

Danielle Hari , Michael A. Beckett , Vikas P. Sukhatme , Mohanraj Dhanabal , Edwardine Nodzenski , Hua Lu , Helena J. Mauceri , Donald W. Kufe , Ralph R. Weichselbaum

引用次数: 32

Overexpression of Cdx1 and Cdx2 Homeogenes Enhances Expression of the HLA-I in HT-29 Cells 过表达Cdx1和Cdx2同源基因可增强HT-29细胞中hla - 1的表达

Molecular cell biology research communications : MCBRC Pub Date : 2000-05-01 DOI: 10.1006/mcbr.2000.0226

Philippe Soubeyran, Gustavo V. Mallo, Virginie Moucadel, Jean-Charles Dagorn, Juan Lucio Iovanna

{"title":"Overexpression of Cdx1 and Cdx2 Homeogenes Enhances Expression of the HLA-I in HT-29 Cells","authors":"Philippe Soubeyran, Gustavo V. Mallo, Virginie Moucadel, Jean-Charles Dagorn, Juan Lucio Iovanna","doi":"10.1006/mcbr.2000.0226","DOIUrl":"10.1006/mcbr.2000.0226","url":null,"abstract":"<div><p>We have previously reported that down-regulation of Cdx1 and Cdx2 mRNA expression is associated with colon carcinogenesis, and that coordinated reexpression of these genes in the HT29 colon cancer-derived cell line leads to a reduced malignant phenotype. Here we show that restoring Cdx1 and Cdx2 expression in HT29 cells enhanced the antigen presentation system, as reflected by a strong induction of the concentration of HLA-I molecules at the cell surface, resulting from increased expression of the HLA-I mRNA. Expression of the LMP2 proteasomal protein was also strongly induced by Cdx1 and Cdx2 at the transcriptional level, whereas TAP1 expression which is under the control of the same bidirectional promoter as LMP2 remained unchanged. Furthermore, expression of the adhesion molecule ICAM-1, which works in concert with HLA-I, and of the cell death promoter Fas was also increased upon Cdx1 and Cdx2 expression. Taken together, these results suggest that loss of Cdx1 and Cdx2 expression during colorectal carcinogenesis could favor the escape of tumor cells from the immune system. In conclusion, restoration of Cdx1 and Cdx2 expression should be considered in immunotherapeutic strategies for colorectal cancer.</p></div>","PeriodicalId":80086,"journal":{"name":"Molecular cell biology research communications : MCBRC","volume":"3 5","pages":"Pages 271-276"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/mcbr.2000.0226","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21799793","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