Somatic Cell Genetics最新文献_第9页

Structural and functional hemi- and dizygous Chinese hamster chromosome 2 gene loci in CHO cells. 中国仓鼠CHO细胞中2号染色体结构和功能的半合和异合基因位点。

Somatic Cell Genetics Pub Date : 1982-07-01 DOI: 10.1007/BF01538704

R L Stallings, M J Siciliano, G M Adair, R M Humphrey

{"title":"Structural and functional hemi- and dizygous Chinese hamster chromosome 2 gene loci in CHO cells.","authors":"R L Stallings, M J Siciliano, G M Adair, R M Humphrey","doi":"10.1007/BF01538704","DOIUrl":"https://doi.org/10.1007/BF01538704","url":null,"abstract":"Fourteen independent somatic cell hybrid clones made between diphtheria toxin (DT)-resistant mouse Cl1D cells and DT-sensitive Chinese hamster ovary (CHO) cells slowly segregated CHO chromosome. Concordant segregation analysis of electrophoretically resolvable Chinese hamster chromosome 2 gene products and CHO chromosomes 2 and Z2 (having q1-q24 deletion) in DT-selected and control hybrid subclones was conducted. Analysis revealed that loci for DT sensitivity and galactose-1-phosphate uridyltransferase could be regionally assigned to Chinese hamster chromosome 2q1-24 and were physically hemizygous in CHO cells. Enolase (ENO1), 6 phosphogluconate dehydrogenase (PGD), and phosphoglucomutase 1 (PGM1) were located outside the q1-24 region on Chinese hamster chromosome 2 and were dizygous in CHO cells. Functional dizygosity of ENO1, PGD, and PGM1 in CHO cells, as determined by the isolation of diploid heterozygous electrophoretic shift mutants following UV and EMS exposure, confirmed their location outside the Z2 deletion and indicated that the deletion did not result in the inactivation of adjacent loci. These results are discussed in relation to current theories on the basis for high frequency of drug-resistant autosomal recessive mutants in CHO cells and conservation of mammalian autosomal linkage groups.","PeriodicalId":21767,"journal":{"name":"Somatic Cell Genetics","volume":"8 4","pages":"413-22"},"PeriodicalIF":0.0,"publicationDate":"1982-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF01538704","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18139095","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: 19

A selection system specific for the Thy mutator phenotype. 一种针对Thy突变表型的特异性选择系统。

Somatic Cell Genetics Pub Date : 1982-07-01 DOI: 10.1007/BF01538705

M Meuth, O Gonçalves, P Thom

引用次数: 19

Generation and chracterization of variants of mouse hepatoma cells with defects in hepato-specific gene expression. I. Albumin synthesis variants. 具有肝特异性基因表达缺陷的小鼠肝癌细胞变异的产生和特征。1 .白蛋白合成变异。

Somatic Cell Genetics Pub Date : 1982-07-01 DOI: 10.1007/BF01538707

G J Darlington, J Papaconstantinou, D W Sammons, P C Brown, E Y Wong, A L Esterman, J Kang

{"title":"Generation and chracterization of variants of mouse hepatoma cells with defects in hepato-specific gene expression. I. Albumin synthesis variants.","authors":"G J Darlington, J Papaconstantinou, D W Sammons, P C Brown, E Y Wong, A L Esterman, J Kang","doi":"10.1007/BF01538707","DOIUrl":"https://doi.org/10.1007/BF01538707","url":null,"abstract":"Clonal variants of mouse hepatoma cells that either fail to produce albumin (variant 19/2) or show significantly reduced levels (100-fold less) of albumin production (variant 1/c/1) were isolated from the parental line. Hepa la, after a single exposure to N-methyl-N'-nitrosoguanidine (MNNG). Intracellular levels of albumin in both variants were below detection by our assay. Analyses by cDNA-RNA reassociation kinetics indicate that there are approximately 3900 molecules of cytoplasmic albumin mRNA per cell in the parent and less than 10 molecules per cell in both variants. Southern blotting of the Eco RI restriction fragments of cellular DNA from the parent and variants did not indicate any major deletions in the albumin gene DNA sequences. We conclude that in the two variants studied, processes that regulate albumin production via alterations in the level of cytoplasmic albumin mRNA have been affected. Our analyses have also shown that alpha-fetoprotein (AFP) production is lacking in one variant (19/2) and is slightly reduced in the other (1/c/1). Transferrin secretion is lower than the parental line in both variants. Thus multiple nonlethal defects in hepatic gene expression can be obtained in Hepa la cells in culture that will be useful in determining the number and kinds of genes that control the expression of liver-specific loci.","PeriodicalId":21767,"journal":{"name":"Somatic Cell Genetics","volume":"8 4","pages":"451-64"},"PeriodicalIF":0.0,"publicationDate":"1982-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF01538707","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17246696","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

Isolation and characterization of Chinese hamster ovary cell mutants resistant to the amino acid analog beta-aspartyl hydroxamate. 氨基酸类似物β -天冬氨酸羟肟酸抗性中国仓鼠卵巢细胞突变体的分离与鉴定。

Somatic Cell Genetics Pub Date : 1982-07-01 DOI: 10.1007/BF01538713

I L Andrulis, L Siminovitch

{"title":"Isolation and characterization of Chinese hamster ovary cell mutants resistant to the amino acid analog beta-aspartyl hydroxamate.","authors":"I L Andrulis, L Siminovitch","doi":"10.1007/BF01538713","DOIUrl":"https://doi.org/10.1007/BF01538713","url":null,"abstract":"Chinese hamster ovary cell lines which are resistant to an amino acid analog, beta-aspartyl hydroxamate, have been isolated and characterized. Mutants resistant to 100-150 microM beta-aspartyl hydroxamate arose from ethyl methane sulfonate-treated parental lines at frequencies of 3.4 x 10(-6) to 1.3 x 10(-7). The mutants fell into at least two genetic classes: 18% of the mutants behaved codominantly in hybrids, the others recessively. Complementation studies indicated that all the recessive mutants belonged to the same class. Mutants selected after one step of mutagenesis overproduce the enzyme asparagine synthetase constitutively with four- to sixfold increases in specific activities over the basal levels of the parental lines. beta-Aspartyl hydroxamate-resistant cell lines with up to 20-fold elevations in asparagine synthetase activity have been isolated after two steps of mutageneis. In addition, highly resistant lines have been selected by long-term growth of a dominant mutant in increasing concentrations of the drug. Resistance in the latter appears to be due not only to overproduction of asparagine synthetase but also to an alteration in the affinity of the enzyme for beta-aspartyl hydroxamate.","PeriodicalId":21767,"journal":{"name":"Somatic Cell Genetics","volume":"8 4","pages":"533-45"},"PeriodicalIF":0.0,"publicationDate":"1982-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF01538713","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17193878","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: 6

Suppression and reexpression of human intestinal-like alkaline phosphatase in intraspecific hybrids. 人肠样碱性磷酸酶在种内杂交种中的抑制和重表达。

Somatic Cell Genetics Pub Date : 1982-07-01 DOI: 10.1007/BF01538709

F J Benham, D Boccelli, H Harris

引用次数: 2

Chromosome-mediated transfer and amplification of an altered mouse dihydrofolate reductase gene. 染色体介导的小鼠二氢叶酸还原酶基因的转移和扩增。

Somatic Cell Genetics Pub Date : 1982-07-01 DOI: 10.1007/BF01538710

D A Haber, R T Schimke

引用次数: 9

alpha 2-Macroglobulin production by cultured human fibroblasts. 培养的人成纤维细胞产生α 2巨球蛋白。

Somatic Cell Genetics Pub Date : 1982-05-01 DOI: 10.1007/BF01538888

J E Brissenden, D W Cox

引用次数: 17

Coexpression of species-specific histone H1 and H2B genes in mouse-rat hybrid cells. 种特异性组蛋白H1和H2B基因在小鼠-大鼠杂交细胞中的共表达。

Somatic Cell Genetics Pub Date : 1982-05-01 DOI: 10.1007/BF01538894

K Ajiro, K Kano-Tanaka, H Higashida, T Tanaka

引用次数: 10

Phenotypic drug resistance in mammalian cells in vitro. 哺乳动物体外细胞的表型耐药。

Somatic Cell Genetics Pub Date : 1982-05-01 DOI: 10.1007/BF01538889

P C Verschure, J W Simons

引用次数: 4

Genetics of receptors for bioactive polypeptides: expression of the human EGF receptor gene and internalization and processing of the receptor-bound EGF in human-mouse cell hybrids. 生物活性多肽受体的遗传学:人EGF受体基因的表达和受体结合的EGF在人-小鼠杂交细胞中的内化和加工。

Somatic Cell Genetics Pub Date : 1982-05-01 DOI: 10.1007/BF01538892

M A Behzadian, Y Shimizu, I Kondo, N Shimizu

{"title":"Genetics of receptors for bioactive polypeptides: expression of the human EGF receptor gene and internalization and processing of the receptor-bound EGF in human-mouse cell hybrids.","authors":"M A Behzadian, Y Shimizu, I Kondo, N Shimizu","doi":"10.1007/BF01538892","DOIUrl":"https://doi.org/10.1007/BF01538892","url":null,"abstract":"We previously postulated that the structural gene for epidermal growth factor (EGF) receptor is located on human chromosome 7 (1,2). In this study, EGF receptor and certain postreceptor functions were further analyzed in a unique cell hybrid line, C2B5, that retains only one human chromosome of an X;7 translocation besides a nearly complete mouse parental genome. Kinetics and Scatchard analysis of [125I]EGF binding to the C2B5 hybrid cells indicated that they carry a single class of EGF receptors with a dissociation constant of 4 x 10(-10) M. The receptors expressed in the hybrids are proven to be immunologically of human nature. The human EGF receptors now embedded in essentially mouse plasma membrane are subject to \"down regulation\" mediated by the ligand EGF. Analysis of the cell-bound EGF indicated that internalization and processing take place in the human-mouse cell hybrids. The degradation of EGF appears to be through a lysosomal pathway since it was substantially delayed or inhibited by lysosomotropic agents.","PeriodicalId":21767,"journal":{"name":"Somatic Cell Genetics","volume":"8 3","pages":"347-62"},"PeriodicalIF":0.0,"publicationDate":"1982-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF01538892","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17349444","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: 13