Genetic mapping of the mouse proto-oncogene c-sis to chromosome 15

The mouse homolog (c-sis) of the transforming gene of the simian sarcoma virus was mapped to chromosome 15 by the Southern blot analysis of DNA's from hamster-mouse somatic cell hybrids. Alterations in c-sis expression may thus play a role in the various murine neoplastic diseases characterized by rearrangements or duplications of chromosome 15.     

Human chromosome 12 is required for elevated HIV-1 expression in human-hamster hybrid cells

Host cell factors act together with regulatory genes of the human immunodeficiency virus (HIV) to control virus production. Human-Chinese hamster ovary hybrid cell clones were used to probe for human chromosomes involved in regulating HIV gene expression. DNA transfection experiments showed that 4 of 18 clones had high levels of HIV gene expression measured by both extracellular virus production and transactivation of the HIV long terminal repeat in the presence of the trans-activator (tat) gene. Karyotype analyses revealed a 94% concordance (17/18) between human chromosome 12 and HIV gene expression. Other chromosomes had an 11 to 72% concordance with virus production.     

Human T-cell receptor alpha-chain genes: location on chromosome 14

The genes encoding the alpha chain of the human T-cell receptor have been mapped to chromosome 14, the chromosome on which the human immunoglobulin heavy chain locus resides. Thus, genes encoding two different classes of antigen receptor are present on the same chromosome. Furthermore, breaks involving chromosome 14 are frequently seen in tumors of T-cell origin. The potential relation of these chromosome abnormalities to alpha-chain genes is discussed.     

哮喘患者12号染色体微卫星不稳定性和杂合性丢失的研究

目的了解广东湛江地区哮喘患者12号染色体微卫星不稳定性（microsatellite instability,MSI）及杂合性丢失（loss of heterozygosity,LOH）情况。方法采用PCR、聚丙烯凝胶电泳及硝酸银染色法对30例哮喘患者和30例健康对照者外周血及痰液DNA中12q13.11-24.31上10个微卫星位点进行检测。结果健康对照者未发现任何微卫星改变现象。30例哮喘患者中,8例（26.7%）患者痰液DNA有一个或多个位点发生微卫星改变（包括MSI和LOH）。结论湛江地区哮喘患者痰液DNA中12号染色体上可检测到MSI和LOH现象。微卫星改变可能与哮喘之间存在一定的相关性,MSI和LOH可能在哮喘发病机制中起一定的作用。     

Human phosphoglycerate kinase and inactivation of the X chromosome

The fibroblasts derived from the skin of a woman heterozygous for an X-linked deficiency of phosphoglycerate kinase represented a mosaic. Two of 22 clones with normal glucose-6-phosphate dehydrogenase activity and hypoxanthine(guanine) phosphoribosyltransferase activity had no phosphoglycerate kinase activity detected by electrophoresis. Because the loci for glucose-6-phosphate dehydrogeniase and hypoxanthine(guanine)phosphoribosyltransferase are already known to undergo inactivation and to be on the short arm of the X chromosome and the locus for phosphoglycerate kinase is on the long arm, these observations support the conclusion that the entire human X chromosome can be involved in X inactivation.     

Human X chromosome carries quantitative genes for immunoglobulin M

Concentrations of immunoglobulin M in serum were one-third higher in females than in males in the Black and White populations of Virginia. In family studies, a much closer correlation was shown between boys and their mothers than between boys and their fathers. The immunoglobulin M concentrations in girls were more closely correlated with those of their fathers than with those of their mothers. The higher mean values for IgM in females and the relative magnitudes of the correlation coefficients between parents and offspring support the hypothesis that the X chromosome of man carries genes with an effect on IgM concentration. These patterns were not demonstrated for immunoglobulins A or G.     

人白细胞介素-12的纯化及鉴定

[目的]利用人白细胞介素-12(human interleukin 12,hIL-12)转基因马铃薯,探讨hIL-12的纯化条件.[方法]提取转基因马铃薯中的总蛋白,hIL-12的分离纯化步骤包括超滤、MKF-AIW阴离子交换层析、MKF-CIC阳离子交换层析.在阴离子交换层析吸附过程中采用试管法选择最佳吸附pH值,选择洗脱过程最佳洗脱pH值;选择阳离子交换层析洗脱过程最佳洗脱pH值;ELISA法测定各纯化阶段收集的上清液或洗脱峰中的hIL-12的含量;非还原SDS-PAGE电泳鉴定蛋白纯度;Western Blot检测纯化的hIL-12.[结果]阴离子交换层析吸附过程最佳吸附pH值为7.5,洗脱过程最佳洗脱pH值为7,阳离子交换层析洗脱过程最佳洗脱pH值为6.5.纯化的hIL-12经非还原SDS-PAGE分析蛋白纯度为91%.Western Blot分析结果表明,在40 kD处有特异的蛋白条带出现.[结论]hIL-12转基因马铃薯经总蛋白提取,超滤,阴离子交换层析,阳离子交换层析纯化,获得了高纯度的hIL-12.     

人白细胞介素-12的纯化及鉴定

[目的]利用人白细胞介素-12(human interleukin 12,hIL-12)转基因马铃薯,探讨hIL-12的纯化条件。[方法]提取转基因马铃薯中的总蛋白,hIL-12的分离纯化步骤包括超滤、MKF-AIW阴离子交换层析、MKF-CIC阳离子交换层析。在阴离子交换层析吸附过程中采用试管法选择最佳吸附pH值,选择洗脱过程最佳洗脱pH值;选择阳离子交换层析洗脱过程最佳洗脱pH值;ELISA法测定各纯化阶段收集的上清液或洗脱峰中的hIL-12的含量;非还原SDS-PAGE电泳鉴定蛋白纯度;Western Blot检测纯化的hIL-12。[结果]阴离子交换层析吸附过程最佳吸附pH值为7.5,洗脱过程最佳洗脱pH值为7,阳离子交换层析洗脱过程最佳洗脱pH值为6.5。纯化的hIL-12经非还原SDS-PAGE分析蛋白纯度为91%。Western Blot分析结果表明,在40 kD处有特异的蛋白条带出现。[结论]hIL-12转基因马铃薯经总蛋白提取,超滤,阴离子交换层析,阳离子交换层析纯化,获得了高纯度的hIL-12。     

转基因马铃薯中纯化人白介素-12的生物学活性分析

分析了转基因马铃薯中纯化人白介素-12（hIL-12）的生物学活性。结果表明,hIL-12纯化品在体外能刺激植物凝集素（PHA）活化的外周血单个核细胞（PBMC）增殖;hIL-12纯化品对人肝癌细胞HepG2．2．15的生长具有抑制作用,且其抑制效果随hIL-12浓度的升高而增强;hIL-12纯化品在体外对乙肝病毒DNA的复制和表面抗原、e抗原的分泌产生抑制作用.     

Human chromosome 21 dosage: effect on the expression of the interferon induced antiviral state

Human primary skin fibroblasts trisomic for chromosome 13, 18, or 21 and diploid human skin fibroblasts were induced for an antiviral response with human interferon. The cells that were trisomnic for chromosome 21 were three to seven times more sensitive to protection by human interferon than the normal diploid or trisomic 18 or 13 fibroblasts. The differential response in trisomnic 21 cells is consistent with the known assignment of the human antiviral gene to chromosome 21.     

Studies of the HER-2/neu proto-oncogene in human breast and ovarian cancer

Carcinoma of the breast and ovary account for one-third of all cancers occurring in women and together are responsible for approximately one-quarter of cancer-related deaths in females. The HER-2/neu proto-oncogene is amplified in 25 to 30 percent of human primary breast cancers and this alteration is associated with disease behavior. In this report, several similarities were found in the biology of HER-2/neu in breast and ovarian cancer, including a similar incidence of amplification, a direct correlation between amplification and over-expression, evidence of tumors in which overexpression occurs without amplification, and the association between gene alteration and clinical outcome. A comprehensive study of the gene and its products (RNA and protein) was simultaneously performed on a large number of both tumor types. This analysis identified several potential shortcomings of the various methods used to evaluate HER-2/neu in these diseases (Southern, Northern, and Western blots, and immunohistochemistry) and provided information regarding considerations that should be addressed when studying a gene or gene product in human tissue. The data presented further support the concept that the HER-2/neu gene may be involved in the pathogenesis of some human cancers.     

Human chromosome banding by Feulgen stain aids in localizing classes of chromatin

The band patterns of human chromosomes displayed by the Feulgen stain are similar to but not identical with those of the conventional quinacrine and Giemsa preparations. The parallelism among the three is principally that of prominent negative bands that appear consistently at characteristic loci throughout a wide range of chromosome compaction. The correlation of those bands with regions of low optical density in nonbanded Fuelgen-stained chromosomes suggests that they are loci of DNA that is inherently difluse or readily labile. The instances of disparity among the patterns of the three modes of banding occur at the telomeres and at known regions of heterochromatin, and are interpreted here as reflecting the heterogeneity of the protein moieties in their reactivity to the cytochemical treatments.     

从转基因马铃薯中纯化的人白细胞介素-12的生物学活性分析

[目的]研究从转人白细胞介素-12（hIL-12）基因马铃薯中纯化的hIL-12的生物学活性。[方法]MTT法检测纯化的hIL-12体外抗肿瘤作用。[结果]纯化的hIL-12在体外对NK敏感肿瘤细胞K562有杀伤作用,而野生对照组无作用。[结论]试验中从转hIL-12基因马铃薯中纯化的hIL-12具有生物学活性。     

人白介素-12转基因马铃薯中hIL-12的表达

[目的]研究人白介素-12转基因马铃薯中hIL-12的表达。[方法]采用ELISA和WesternBlot,检测转基因马铃薯中hIL-12的表达情况。[结果]转基因马铃薯叶与块茎中均能被hIL-12p70二聚体特异性的抗体识别的蛋白表达,与野生对照组相比均有0.01水平显著差异。WesternBlot分析结果显示,在40kD处有特异性的蛋白条带出现。[结论]所建立的人白介素-12转基因马铃薯表达体系能正确、有效表达hIL-12二聚体。     

Human T cell leukemia viruses use a receptor determined by human chromosome 17

Human T cell leukemia viruses (HTLV-I and HTLV-II) can infect many cell types in vitro. HTLV-I and HTLV-II use the same cell surface receptor, as shown by interference with syncytium formation and with infection by vesicular stomatitis virus (VSV) pseudotypes bearing the HTLV envelope glycoproteins. Human-mouse somatic cell hybrids were used to determine which human chromosome was required to confer susceptibility to VSV(HTLV) infection. The only human chromosome common to all susceptible cell hybrids was chromosome 17, and the receptor gene was localized to 17cen-qter. Antibodies to surface antigens known to be determined by genes on 17q did not block the HTLV receptor.     

Role of the kinase MST2 in suppression of apoptosis by the proto-oncogene product Raf-1

The ablation of the protein kinase Raf-1 renders cells hypersensitive to apoptosis despite normal regulation of extracellular signal-regulated kinases, which suggests that apoptosis protection is mediated by a distinct pathway. We used proteomic analysis of Raf-1 signaling complexes to show that Raf-1 counteracts apoptosis by suppressing the activation of mammalian sterile 20-like kinase (MST2). Raf-1 prevents dimerization and phosphorylation of the activation loop of MST2 independently of its protein kinase activity. Depletion of MST2 from Raf-1-/- mouse or human cells abrogated sensitivity to apoptosis, whereas overexpression of MST2 induced apoptosis. Conversely, depletion of Raf-1 from Raf-1+/+ mouse or human cells led to MST2 activation and apoptosis. The concomitant depletion of both Raf-1 and MST2 prevented apoptosis.