Cell regulation最新文献_第6页

Identification of a cell retention signal in the B-chain of platelet-derived growth factor and in the long splice version of the A-chain. 血小板源性生长因子b链和a链长剪接中细胞保留信号的鉴定。

Cell regulation Pub Date : 1991-07-01 DOI: 10.1091/mbc.2.7.503

A Ostman, M Andersson, C Betsholtz, B Westermark, C H Heldin

{"title":"Identification of a cell retention signal in the B-chain of platelet-derived growth factor and in the long splice version of the A-chain.","authors":"A Ostman, M Andersson, C Betsholtz, B Westermark, C H Heldin","doi":"10.1091/mbc.2.7.503","DOIUrl":"https://doi.org/10.1091/mbc.2.7.503","url":null,"abstract":"The B-chain homodimer of platelet-derived growth factor (PDGF) is only very inefficiently secreted and remains largely associated with the producer cell; in contrast, the dimer of the short, and most common, splice variant of the A-chain is secreted. To identify the structural background to the differences in the secretory pattern between the different isoforms of PDGF, a set of chimeric PDGF A/B cDNAs was generated and expressed in COS cells. Analyses of the biosynthesis and processing of the corresponding products led to the identification of a determinant for cell association in the carboxy-terminal third of the PDGF B-chain precursor. Introduction of stop codons at various positions in the carboxy-terminal prosequence of the PDGF B-chain localized this determinant to an 11-amino-acid-long region (amino acids 219-229). This region contains an 8-amino-acid-long basic sequence that is homologous to a sequence present in an alternatively spliced longer version of the PDGF A-chain. In contrast to the short splice variant, the long splice A-chain version, like the B-chain, was found to remain predominantly cell associated. Thus, we have identified a conserved sequence that inhibits the secretion of some of the PDGF isoforms. Our data also suggest that switching of splicing patterns can be a mechanism to regulate the formation of secreted or cell-associated forms of PDGF-AA and possibly other growth factors.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.7.503","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12944953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 129

Ca(2+)-induced Ca2+ release amplifies the Ca2+ response elicited by inositol trisphosphate in macrophages. Ca(2+)诱导的Ca2+释放放大了三磷酸肌醇在巨噬细胞中引发的Ca2+反应。

Cell regulation Pub Date : 1991-07-01 DOI: 10.1091/mbc.2.7.513

C Randriamampita, G Bismuth, A Trautmann

{"title":"Ca(2+)-induced Ca2+ release amplifies the Ca2+ response elicited by inositol trisphosphate in macrophages.","authors":"C Randriamampita, G Bismuth, A Trautmann","doi":"10.1091/mbc.2.7.513","DOIUrl":"https://doi.org/10.1091/mbc.2.7.513","url":null,"abstract":"We have studied the rise in intracellular calcium concentration ([Ca2+]i) elicited in macrophages stimulated by platelet-activating factor (PAF) by using fura-2 measurements in individual cells. The [Ca2+]i increase begins with a massive and rapid release of Ca2+ from intracellular stores. We have examined the mechanism of this Ca2+ release, which has been generally assumed to be triggered by inositol trisphosphate (IP3). First, we confirmed that IP3 plays an important role in the initiation of the PAF-induced [Ca2+]i rise. The arguments are 1) an increase in IP3 concentration is observed after PAF stimulation; 2) injection of IP3 mimics the response to PAF; and 3) after introduction of heparin in the cell with a patch-clamp electrode, the PAF response is abolished. Second, we investigated the possibility of an involvement of Ca(2+)-induced Ca2+ release (CICR) in the development of the Ca2+ response. Ionomycin was found to elicit a massive Ca2+ response that was inhibited by ruthenium red or octanol and potentiated by caffeine. The PAF response was also inhibited by ruthenium red or octanol and potentiated by caffeine, suggesting that CICR plays a physiological role in these cells. Because our results indicate that in this preparation IP3 production is not sensitive to [Ca2+]i, CICR appears as a primary mechanism of positive feedback in the Ca2+ response. Taken together, the results suggest that the response to PAF involves an IP3-induced [Ca2+]i rise followed by CICR.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.7.513","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12944954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 20

Genetic fine-structural analysis of the Saccharomyces cerevisiae alpha-pheromone receptor. 酿酒酵母α信息素受体的遗传精细结构分析。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.439

J B Konopka, D D Jenness

{"title":"Genetic fine-structural analysis of the Saccharomyces cerevisiae alpha-pheromone receptor.","authors":"J B Konopka, D D Jenness","doi":"10.1091/mbc.2.6.439","DOIUrl":"https://doi.org/10.1091/mbc.2.6.439","url":null,"abstract":"The alpha-pheromone receptor encoded by the STE2 gene contains seven potential transmembrane domains. Its ability to transduce the pheromone signal is thought to require the action of a G protein. As an initial step toward defining the structural features of the receptor required for its activity, we examined the phenotypic consequences of linker insertion mutations (12 bp) at 10 different sites in the STE2 gene. Three mutant classes, which correspond to three different regions of the receptor protein, were observed. 1) The two mutants affecting the C-terminal region (C-terminal mutants) were essentially wild type for mating efficiency, pheromone binding, and pheromone sensitivity. 2) The three mutants in the N-terminus mated with reduced efficiency, showed reduced pheromone binding capacity, and were partially defective in pheromone induction of agglutinin production and cell division arrest. Increased gene dosage of these N-terminal alleles suppressed their mutant phenotypes, whereas the sst2-1 mutation, which blocks adaptation to pheromone, did not result in suppression. Thus, the N-terminal mutants were apparently limited by receptor production, but not by the adaptation function SST2. 3) The five mutants in the central region containing the seven transmembrane segments (central mutants) were completely defective for mating and did not respond to pheromone, but could be distinguished by their ability to bind pheromone. Inserts in or near transmembrane domains 2 and 4 blocked pheromone binding, whereas inserts into transmembrane domains 1, 5, and 6 retained partial pheromone binding activity even though they failed to transduce a signal. The central mutants were not suppressed by increased gene dosage, and one mutant (ste2-/101) was partially suppressed by sst2-1. Furthermore, the central core mutants were also distinguished from one another in that three of the five mutants were able to partially complement the temperature sensitivity of ste2-3.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.6.439","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12819243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

Localization of transforming growth factor-beta 1 in mitochondria of murine heart and liver. 转化生长因子- β 1在小鼠心脏和肝脏线粒体中的定位。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.467

U I Heine, J K Burmester, K C Flanders, D Danielpour, E F Munoz, A B Roberts, M B Sporn

引用次数: 15

A function for the integrin alpha 6 beta 4 in the hemidesmosome. 半染色体中整合素的函数。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.427

J C Jones, M A Kurpakus, H M Cooper, V Quaranta

{"title":"A function for the integrin alpha 6 beta 4 in the hemidesmosome.","authors":"J C Jones, M A Kurpakus, H M Cooper, V Quaranta","doi":"10.1091/mbc.2.6.427","DOIUrl":"https://doi.org/10.1091/mbc.2.6.427","url":null,"abstract":"Many epithelial cells appear to use cell-substratum adhesion complexes known as hemidesmosomes as the main means of anchorage to the connective tissue. Initially recognized as distinctive electron-dense images, hemidesmosomes are still poorly understood at the biochemical level. The regulation and mode of their assembly, which is disrupted in certain blistering diseases and is critical to proper wound repair, also remains to be elucidated. The integrin alpha 6 beta 4 is expressed along the basal surface of various epithelial cells. We show here that this integrin localizes to hemidesmosomes as determined by immunoelectron microscopy using antibodies directed against both the extra- and intracytoplasmic domains of alpha 6 beta 4. This result, which agrees with a recent study, suggests a functional role for the alpha 6 beta 4 integrin in the hemidesmosomes. We therefore investigated such a potential role for this integrin using the cultured rat bladder carcinoma cell line 804G, which has the uncommon ability to form hemidesmosomes in vitro when maintained on uncoated glass substrates. By immunoprecipitation and immunofluorescence, we show that 804G cells express alpha 6 beta 4 along their basal surface in a punctate pattern that overlaps with the distribution of hemidesmosomal plaque antigens. However, this pattern is altered when cells are plated in the presence of an antiserum directed against alpha 6 beta 4. Furthermore, no hemidesmosomes are detectable at the ultrastructural level in the alpha 6 beta 4 antibody-treated cells compared with control cells. These results indicate that integrins may play a critical role in assembly and adhesive functions of the hemidesmosome.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.6.427","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13043534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 178

sar1, a gene from Schizosaccharomyces pombe encoding a protein that regulates ras1. sar1是一种来自裂糖菌pombe的基因，它编码一种调节ras1的蛋白质。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.453

Y Wang, M Boguski, M Riggs, L Rodgers, M Wigler

引用次数: 52

Functions of the major tyrosine phosphorylation site of the PDGF receptor beta subunit. PDGF受体β亚基主要酪氨酸磷酸化位点的功能。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.413

A Kazlauskas, D L Durden, J A Cooper

{"title":"Functions of the major tyrosine phosphorylation site of the PDGF receptor beta subunit.","authors":"A Kazlauskas, D L Durden, J A Cooper","doi":"10.1091/mbc.2.6.413","DOIUrl":"https://doi.org/10.1091/mbc.2.6.413","url":null,"abstract":"Two tyrosine phosphorylation sites in the human platelet-derived growth factor receptor (PDGFR) beta subunit have been mapped previously to tyrosine (Y)751, in the kinase insert, and Y857, in the kinase domain. Y857 is the major site of tyrosine phosphorylation in PDGF-stimulated cells. To evaluate the importance of these phosphorylations, we have characterized the wild-type (WT) and mutant human PDGF receptor beta subunits in dog kidney epithelial cells. Replacement of either Y751 or Y857 with phenylalanine (F) reduced PDGF-stimulated DNA synthesis to approximately 50% of the WT level. A mutant receptor with both tyrosines mutated was unable to initiate DNA synthesis, as was a kinase-inactive mutant receptor. Transmodulation of the epidermal growth factor receptor required Y857 but not Y751. We also tested the effects of phosphorylation site mutations on PDGF-stimulated receptor kinase activity. PDGF-induced tyrosine phosphorylation of two cellular proteins, phospholipase C gamma 1 (PLC gamma 1) and the GTPase activating protein of Ras (GAP), was assayed in epithelial cells expressing each of the mutant receptors. Tyrosine phosphorylation of GAP and PLC gamma 1 was reduced markedly by the F857 mutation but not significantly by the F751 mutation. Reduced kinase activity of F857 receptors was also evident in vitro. Immunoprecipitated WT receptors showed a two- to fourfold increase in specific kinase activity if immunoprecipitated from PDGF-stimulated cells. The F751 receptors showed a similar increase in activity, but F857 receptors did not. Our data suggest that phosphorylation of Y857 may be important for stimulation of kinase activity of the receptors and for downstream actions such as epidermal growth factor receptor transmodulation and mitogenesis.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.6.413","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12819242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 74

Requirement of the adenovirus E1A transformation domain 1 for inhibition of PC12 cell neuronal differentiation. 腺病毒E1A转化结构域1对抑制PC12细胞神经元分化的要求。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.479

L E Heasley, S Benedict, J Gleavy, G L Johnson

{"title":"Requirement of the adenovirus E1A transformation domain 1 for inhibition of PC12 cell neuronal differentiation.","authors":"L E Heasley, S Benedict, J Gleavy, G L Johnson","doi":"10.1091/mbc.2.6.479","DOIUrl":"https://doi.org/10.1091/mbc.2.6.479","url":null,"abstract":"Expression of the adenovirus early gene E1A inhibits the nerve growth factor (NGF)-induced differentiation of PC12 pheochromocytoma cells. Expression of the 12S form of E1A, which lacks the transcription activation region, also inhibited PC12 cell differentiation in a manner similar to the wild-type gene. Three cellular proteins--the retinoblastoma susceptibility gene product referred to as 105(Rb)-, 107-, and 300-kDa proteins--stably interacted with the different E1A polypeptides. Analysis of the association of these cellular proteins with mutant E1A polypeptides demonstrated that a functional domain 1, which is minimally involved in the association of the 300-kDa protein with E1A, was sufficient to inhibit neuronal differentiation. Deletion of transformation domain 2, which encodes sequences necessary for the binding of the 105(Rb)- and 107-kDa proteins, did not influence the ability of the mutant E1A polypeptide to inhibit PC12 cell differentiation. E1A was also shown to alter the expression of mRNAs for the early response genes c-fos, c-myc, egr-1, and c-jun and their regulation in response to NGF. In clones expressing either 12S or 13S E1A, NGF stimulation of c-fos and c-myc was repressed. In contrast, basal mRNA levels for c-jun and egr-1 were constitutively elevated and not significantly affected further by challenge with NGF. Simply expressing c-jun by gene transfer, however, did not mimic the action of E1A because constitutively expressing c-jun clones differentiated in response to NGF. Thus, expression of the E1A polypeptide disrupts NGF control of early transcription events that have been shown to be critical for PC12 cell neuronal differentiation.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.6.479","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12993268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 30

Overexpression of the alpha-type protein kinase (PK) C in LLC-PK1 cells does not lead to a proportional increase in the induction of two 12-O-tetradecanoylphorbol-13-acetate-inducible genes. 在LLC-PK1细胞中，α型蛋白激酶(PK) C的过表达不会导致两个12- o - tetradecanoylphorbol13 -acetate诱导基因的诱导成比例增加。

Cell regulation Pub Date : 1991-06-01 DOI: 10.1091/mbc.2.6.491

M Wartmann, D A Jans, P J Parker, Y Nagamine, B A Hemmings, S Jaken, U Eppenberger, D Fabbro

{"title":"Overexpression of the alpha-type protein kinase (PK) C in LLC-PK1 cells does not lead to a proportional increase in the induction of two 12-O-tetradecanoylphorbol-13-acetate-inducible genes.","authors":"M Wartmann, D A Jans, P J Parker, Y Nagamine, B A Hemmings, S Jaken, U Eppenberger, D Fabbro","doi":"10.1091/mbc.2.6.491","DOIUrl":"https://doi.org/10.1091/mbc.2.6.491","url":null,"abstract":"Phorbol esters, by activating protein kinase C (PKC), induce the expression of the urokinase-type plasminogen activator (uPA) gene and the proto-oncogene c-fos in LLC-PK1 (PK1) porcine kidney epithelial cells. To investigate the role of PKC in the regulation of these two 12-O-tetradecanoylphorbol-13-acetate (TPA)-inducible genes, the alpha-type PKC, the predominant subtype present in the PK1 cells, was overexpressed in this cell line. Two clonal PK1 derivatives overexpressing the alpha PKC 15- and 20-fold, respectively, were established. Compared with the parental and control cells, only a modest but substantially sustained (2- to 3-fold) increase in the accumulation of uPA as well as c-fos mRNAs were observed by TPA in these cells. These results indicate that the extent of induction of these genes mediated by TPA was not proportional to the amounts of alpha-type PKC stably overexpressed in these cells, suggesting that factor(s) downstream of the activation of the alpha PKC appear to be rate limiting for the induction of both TPA-inducible genes in PK1 cells.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.6.491","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13069352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Noncontiguous regions in the extracellular domain of EGF receptor define ligand-binding specificity. EGF受体细胞外区域的不连续区域定义了配体结合特异性。

Cell regulation Pub Date : 1991-05-01 DOI: 10.1091/mbc.2.5.337

I Lax, R Fischer, C Ng, J Segre, A Ullrich, D Givol, J Schlessinger

{"title":"Noncontiguous regions in the extracellular domain of EGF receptor define ligand-binding specificity.","authors":"I Lax, R Fischer, C Ng, J Segre, A Ullrich, D Givol, J Schlessinger","doi":"10.1091/mbc.2.5.337","DOIUrl":"https://doi.org/10.1091/mbc.2.5.337","url":null,"abstract":"Murine epidermal growth factor (EGF) binds with approximately 250-fold higher binding affinity to the human EGF receptor (EGFR) than to the chicken EGFR. This difference in binding affinity enabled the identification of a major ligand-binding domain for EGF by studying the binding properties of various chicken/human EGFR chimera expressed in transfected cells lacking endogenous EGFR. It was shown that domain III of EGFR is a major ligand-binding region. Here, we analyze the binding properties of novel chicken/human chimera to further delineate the contact sequences in domain III and to assess the role of other regions of EGFR for their contribution to the display of high-affinity EGF binding. The chimeric receptors include chicken EGFR containing domain I of the human EGFR, chicken receptor containing domain I and III of the human EGFR, and two chimeric chicken EGFR containing either the amino terminal or the carboxy terminal halves of domain III of human EGFR, respectively. In addition, the binding of various human-specific anti-EGFR monoclonal antibodies that interfere with EGF binding is also compared. It is concluded that noncontiguous regions of the EGFR contribute additively to the binding of EGF. Each of the two halves of domain III has a similar contribution to the binding energy, and the sum of both is close to that of the entire domain III. This suggests that the folding of domain III juxtaposes sequences that together constitute the ligand-binding site. Domain I also provides a contribution to the binding energy, and the added contributions of both domain I and III to the binding energy generate the high-affinity binding site typical of human EGFR.","PeriodicalId":9671,"journal":{"name":"Cell regulation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1991-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1091/mbc.2.5.337","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12880789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 58