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1.
Extracellular superoxide dismutase (EC-SOD) is the major SOD isoenzyme in extracellular fluids, but occurs also in tissues. The sites and characteristics of the synthesis of the enzyme are unknown. The occurrence of EC-SOD in cultures of a large panel of human cell lines was assayed by means of an e.l.i.s.a. Unlike the situation for the intracellular isoenzymes CuZn-SOD and Mn-SOD, expression of EC-SOD occurs in only a few cell types. None of the ten investigated suspension-growing cell lines produced EC-SOD. Among normal diploid anchorage-dependent cell lines, expression was found in all 25 investigated fibroblast cell lines, in the two glia-cell lines, but not in six endothelial-cell lines, two epithelial-cell lines or in two amnion-derived lines. Among neoplastic anchorage-dependent cell lines expression was found in 13 out of 29. EC-SOD was secreted into the culture medium by cell lines expressing the enzyme. The rate of EC-SOD synthesis varied by nearly 100-fold among the fibroblast lines and remained essentially constant in the individual lines during long-term culture. In the nine investigated cases, the secreted EC-SOD was of the high-heparin-affinity C type. It is suggested that tissue EC-SOD is secreted by a few well-dispersed cell types, such as fibroblasts and glia cells, to diffuse subsequently around and reversibly bind to heparan sulphate proteoglycan ligands in the glycocalyx of the surface of most tissue cell types and in the interstitial matrix.  相似文献   

2.
Total thirty throe parents of hybrid rice ( Oryza sativa L. ), including twenty five rice male sterile lines, throe maintainer lines and five restore lines, were analyzed by using twenty SSR (simple sequence repeats) primer pairs which disperse on 12 chromosomes in rice. Those primers detected 102 alleles among 33 parents of hybrid rice. PIC (polymorphic index content) values ranged from 0.274 to 0.773. PIC value is 0.554 on the average. Five SSR primer pairs selected from fifty six primer pairs can distinguish individually all of the rice male sterile lines and restore lines in the present study. As results from cluster analysis, it was concluded as follows. (1) Rice male sterile lines have abundant genetic diversity in China. Genetic background was vulnerable among rice male sterile lines used in large scale. (2) In indica rice, genetic variation of the restored lines is larger than that of the male sterile lines. (3) The restored lines were clustered separately from the male sterile lines which are grown widely for production.  相似文献   

3.
用微卫星DNA标记检测中国主要杂交水稻亲本的遗传差异   总被引:35,自引:0,他引:35  
选用分布于水稻(OryzasativaL.)12条染色体上的20对SSR(Simplesequencerepeats)引物,分析了具有多种质源和较大应用面积的24个水稻胞质雄性不育系、1个光(温)敏核不育系、3个保持系和5个生产中应用较广的恢复系。在以上33份杂交水稻亲本材料间共检测出102个等位基因(alleles),平均每对SSR引物可检测到5.1个等位基因。PIC(polymorphicindexcontent)值的变动范围为0.274~0.773,平均PIC值为0.554。从56对SSR引物中筛选出5对引物,能够有效地区分所有供试的水稻雄性不育系和恢复系。杂交水稻亲本的聚类分析表明:(1)我国水稻雄性不育系遗传变异丰富,但生产中主要应用的水稻雄性不育系遗传背景比较单一。(2)生产中应用面积较大的水稻雄性不育系遗传变异较恢复系差。(3)生产中主要应用的水稻雄性不育系与恢复系分别聚类于不同的类群,且遗传关系较远。  相似文献   

4.
5.
The literature on cell lines that have been developed from rainbow trout (RT) (Oncorhynchus mykiss) is reviewed to illustrate three new terms: invitromatics, invitrome, and invitroomics. Invitromatics is defined as the history, development, characterization, engineering, storage, and sharing of cell lines. RT invitromatics differs from invitromatics for humans and other mammals in several ways. Nearly all the RT cell lines have developed through spontaneous immortalization. No RT cell line undergoes senescence and can be described as being finite, whereas many human cell lines undergo senescence and are finite. RT cell lines are routinely grown at 18–22°C in free gas exchange with air in basal media developed for mammalian cells together with a supplement of fetal bovine serum. An invitrome is defined as the grouping of cell lines around a theme or category. The broad theme in this article is all the cell lines that have ever been created from O. mykiss, or in other words, the RT invitrome. The RT invitrome consists of approximately 55 cell lines. These cell lines can also be categorized on the basis of their storage and availability. A curated invitrome constitutes all the cell lines in a repository and for RT consists of 11 cell lines. These consist of epithelial cell lines, such as RTgill-W1, and fibroblast cell lines, such as RTG-2. RTG-2 can be purchased from a scientific company and constitutes the commercial RT invitrome. Cell lines that are exchanged between researchers are termed the informally shared invitrome and for RT consists of over 35 cell lines. Among these is the monocyte/macrophage cell line, RTS11. Cell lines whose existence is in doubt are termed the zombie invitrome, and for RT, approximately 12 cell lines are zombies. Invitroomics is the application of cell lines to a scientific problem or discipline. This is illustrated with the use of the RT invitrome in virology. Of the RT invitrome, RTG-2 was the most commonly used cell line to isolate viruses. Fifteen families of viruses were studied with RT invitrome. RT cell lines were best able to support replication of viruses from the Herpesviridae, Iridoviridae, Birnaviridae, Togaviridae, and Rhabdoviridae families.  相似文献   

6.
Soto I  Cortese M  Carreira V  Folguera G  Hasson E 《Genetica》2006,127(1-3):199-206
We assessed the indirect response of longevity in lines selected for wing length (WL) and developmental time (DT). Longevity in selection lines was compared to laboratory control lines and the offspring of recently collected females. Wild flies (W lines), flies from lines selected for fast development (F lines), and for fast development and large wing length (L lines) outlived control laboratory lines (C lines) and lines selected for fast development and short wing (S lines). The decline in longevity in S lines is in line with the idea that body size and longevity are correlated and may be the result of the fixation of alleles at loci affecting pleiotropically the two traits under selection and longevity. In addition, inbreeding and artificial selection affected the correlation between wing length and longevity that occurs in natural populations of Drosophila buzzatii, suggesting that correlations between traits are not a perdurable feature in a population.  相似文献   

7.
辣椒胞质雄性不育系和保持系内源激素含量的比较   总被引:3,自引:0,他引:3  
以2个辣椒品系(199807、199803)的胞质雄性不育系和相应保持系为实验材料,采用酶联免疫吸附法(ELISA)测定IAA、(Z ZR)、GA3和ABA等内源激素含量,用气相色谱分析仪测定乙烯(ETH)释放量,对辣椒胞质雄性不育系和相应保持系内源激素含量变化规律进行研究.实验结果表明:在四分小孢子之前,花药中的IAA含量不育系显著高于保持系,在四分小孢子时期花药和花蕾中的IAA含量出现转折,到花粉粒成熟期的花蕾和花药以及开花期叶片中的IAA含量均是不育系显著低于保持系;小孢子各发育时期花药以及花期叶片中GA3含量均是不育系高于保持系,但花粉粒成熟期化蕾中GA3含量为不育系低于保持系;小孢子不同发育时期的花药以及花期叶片中ABA含量始终足不育系显著高于保持系,而花粉粒成熟期花蕾中ABA含量不育系与保持系没有显著差异;花粉粒成熟期的花蕾和花期叶片中ETH释放量表现为不育系显著高于保持系.同时,花粉粒成熟期的花蕾、花药和叶片中IAA/ABA、(Z ZR)/ABA、GA3/ABA、IAA/GA3、(Z ZR)/GA3等5个激素的比值均有不育系低于保持系的趋势.本实验结果说明辣椒的育性表现与花器和叶片等组织中内源激素的含量变化有关,花药和花期叶片中IAA亏缺、GA3和ABA增加以及化蕾和叶片中ETH过度产生,都有可能导致辣椒雄性不育.  相似文献   

8.
Evidence for correlated responses to selection was investigated in lines of rats selected for 13 generations for high (U line) and low (D line) 3-9-week gain in comparison with random-bred control lines (R and C lines). The increase in 3-9-week gain in the U lines was shown to be due largely to an increase in 9-week weight, although 3-week weight also increased in these lines. In the D lines, where a marked decrease in 3-9-week gain was observed, this was found to be due to a large decrease in 9-week weight and no detectable change in 3-week weight. The average 2-week litter weight, a measure of the lactational performance of the dam, was significanly greater in the U lines than in the D lines. Selection for 3-9-week gain in these lines of rats led to changes of litter size at birth in the same direction as that of selection. This resulted in a significantly higher litter size in the U lines than in the D lines. The number of rats alive 2 and 9 weeks of age and the percentage of mated females pupping were similar in the U and D lines but lower in these lines than the random bred C lines, providing evidence for a reduction of "fitness" in the selected lines. Carcass composition was studied for all lines at the 11th generation of selection. Carcass composition, in terms of water, fat, ash and protein, was similar in the R and C lines. The U lines had more water and lesss fat than the R or C line. The D lines had similar carcass composition to the R and C lines. It is suggested that these selected and random-bred lines of rats are potentially useful animals to investigate further the developmental and physiological mechanisms which control growth.  相似文献   

9.
Plants can be genetically engineered for virus resistance by transformation with a viral gene. We transformed tobacco with the tomato spotted wilt virus (TSWV) nucleocapsid gene from the Hawaiian L isolate in order to obtain TSWV resistant breeding lines. Doubled-haploid lines were produced from primary transgenic plants that were selected for resistance to the virus. Several of these lines showed very high levels of resistance and were symptomless after inoculation with the Hawaiian L isolate of TSWV. The accumulation of only low levels of full-length transgene RNA and protein observed in these lines is consistent with an RNA-mediated mechanism of resistance. The lines that were highly resistant to the Hawaiian L isolate of TSWV were also found to be highly resistant to several other isolates of TSWV, while lines that were only moderately resistant to the Hawaiian L isolate were often susceptible to the other isolates. The highly resistant lines were advanced over several generations by self-pollination. Although these lines were fully homozygous, several lines lost resistance in later generations, indicating that the resistance was unstable. Selection for resistance in these unstable lines did not prevent the occurrence of susceptible progeny in subsequent generations. Therefore, testing over several generations is required to determine the stability of resistance when breeding crops with transgenic virus resistance.  相似文献   

10.
Induction of 2'-5'-oligoadenylatesynthetase (2-5A synthetase) by interferons and theophylline by means of activation of cAMP-system in interferon susceptible and resistant cell lines were studied. In interferon resistant cell lines the basal activity of 2-5A synthetase exceeded the level of the same enzyme in interferon susceptible cell lines. Activity of 2-5A synthetase is increased in interferon susceptible cell lines by interferon treatment, but the activity of the enzyme is not altered in interferon resistant cell lines. Among the studied cell lines the induction of 2-5A synthetase by theophylline was possible only in L929 cell line. The common mechanism for the absence of 2-5A synthetase induction by interferon and theophylline in interferon resistant cells is discussed.  相似文献   

11.
Certain newly established Epstein-Barr virus-containing Burkitt's lymphoma cell lines do not express the cytotoxic T-lymphocyte-detected membrane antigen (LYDMA) through which EBV infection is normally controlled by the host. When the EB virus recovered from these BL lines was used to transform peripheral blood lymphocytes from seronegative donors, the lymphoblastoid cell lines (LCLs) that arose were all LYDMA positive. This indicates that the LYDMA-negative nature of the BLs is not the result of a mutation in the resident viral genome but is rather a specific adaptation in those cells, perhaps permitting evasion of the host immune surveillance in tumour development. A comparison of the EBV gene expression in six LYDMA-negative and two LYDMA-positive BL lines and in their corresponding LCLs revealed that several of the BL lines did not express all of the viral gene products classically associated with latent transformation by EBV. Four out of eight cell lines showed restricted expression of the latent membrane protein (LMP) and/or the EB nuclear antigen, EBNA 2. A new level of EBV gene regulation therefore appears to be operating in some of the BL cell lines. The patterns of expression of EBV genes in the cell lines did not show any correlation with the known susceptibility of the lines to T cell killing.  相似文献   

12.
With the aid of the C-method of chromosome staining marker chromosomes three classes of human continuous cell lines were studied: 1) HeLa and HeLa-like cell lines (HEp-2, U, KB); 2) non-HeLa cell lines, with type B mobility of glucose-6-phosphate-dehydrogenase (HOS, A-549, A-204); 3) lymphoblastoid cell lines (Raji, Namalva, L-101). Two C-marker chromosomes were observed in two investigated cell lines A-204 and KB, one C-marker chromosome was observed in HEp-2, HeLa, U, A-549, Namalva cell lines; C-markers were absent in HOS and L-101 cell lines. Y-chromosome was found in Raji, A-549 and L-101 cell lines. The C-method of chromosome staining is a simple method, promoting an intraspecific identification of human cell lines.  相似文献   

13.
Some anti-murine transferrin receptor monoclonal antibodies block iron uptake in mouse cell lines and inhibit cell growth. We report here the selection and characterization of mutant murine lymphoma cell lines which escape this growth inhibition by anti-transferrin receptor antibody. Growth assays and immunoprecipitation of transferrin receptor in hybrids between independently derived mutants or between mutants and antibody-susceptible parental cell lines indicate that all of the selected lines have a similar genetic alteration that is codominantly expressed in hybrids. Anti-transferrin receptor antibodies and transferrin itself still bind to the mutant lines with saturating levels and Kd values very similar to those of the parental lines. However, reciprocal clearing experiments by immunoprecipitation and reciprocal blocking of binding to the cell surface with two anti-transferrin receptor antibodies indicate that the mutant lines have altered a fraction of their transferrin receptors such that the growth-inhibiting antibody no longer binds, whereas another portion of their transferrin receptors is similar to those of the parental lines and binds both antibodies. These results argue that the antibody-selected mutant cell lines are heterozygous in transferrin receptor expression, probably with a mutation in one of the transferrin receptor structural genes.  相似文献   

14.
Transverse lines in long bones of prehistoric California Indians   总被引:1,自引:0,他引:1  
Radiopaque transverse lines (lines of arrested growth, Harris's lines) were counted on X-rays of the distal end of 102 adult femurs from prehistoric California Indian populations representing three archaeological Horizons. The sample from Early Horizon has the highest frequency of lines, the Middle Horizon the next, and the sample from Late Horizon has the lowest frequency of lines. These differences are statistically significant. Archaeological evidence indicates that the Indians improved and broadened their subsistence economy from Early to Late Horizon. It is concluded that the differences in the frequency of lines among the three California Indian populations probably are associated with differences in morbidity and/or nutritional status of the people. If this hypothesis is correct, then frequency distribution of transverse lines represents a valuable tool for the paleopathologist and the archaeologist.  相似文献   

15.
16.
不同结构的外源ACO基因导入香石竹对瓶插寿命的影响   总被引:13,自引:0,他引:13  
余义勋  包满珠   《生物工程学报》2004,20(5):704-707
以香石竹叶片为外植体 ,利用根癌农杆菌 (Agrobacteriumtumefaciens)介导法 ,将香石竹ACC氧化酶 (ACO)基因核DNA的正义 (sense)、反义 (antisense)、正义重复 (sensedirectrepeat)和反义重复 (antisensedirectrepeat)等 4种T DNA结构导入香石竹‘Master’品种。经Southern杂交检测证明目的基因已整合到香石竹基因组 ,共获得 14个转化株系。在 25℃条件下比较瓶插寿命 ,对照植株花朵瓶插寿命为 5.8d ,多数转化株系花朵瓶插寿命达 11d ,最长者可达 12.8d。大多数转基因株系切花衰老过程中乙烯释放量显著减少 ,部分转基因株系切花衰老过程中几乎检测不到乙烯 ,而对照有明显的峰值。通过对本研究转化ACO基因核DNA与前人转化ACO基因cDNA延长瓶插寿命比较以及对不同T DNA结构的转化抑制内源基因表达的程度进行比较后 ,初步判断用核DNA转化后对内源基因的抑制效果与cDNA相当甚至更明显 ,反义基因可以比正义基因更有效地抑制内源的同源基因的表达 ,转重复基因比转单个基因能更有效地抑制内源的同源基因的表达。  相似文献   

17.
H Zhou  S J Lamont 《Animal genetics》1999,30(4):256-264
Forty-two microsatellite loci were analysed in 23 highly inbred chicken lines derived from Leghorn, Jungle Fowl, Fayoumi and Spanish breeds. Line-specific alleles among breeds and lines were detected. The band-sharing (BS) values were calculated and the proportion of shared alleles distances (Dps) were estimated. The BS values and Dps between sets of MHC-congenic lines ranged from 0.74 to 0.96, and 0.05-0.35, respectively. The BS values between each pair of noncongenic Leghorn lines were 0.32-0.97, and between Leghorn and exotic (Jungle Fowl, Fayoumi and Spanish) breeds were 0.03-0.55. The Dps between Fayoumi lines and other lines were much larger (0.66-1.34) than within Leghorns, and the Jungle Fowl breed had the largest distances with other lines (1.12-5.38). The phylogenetic consensus tree that was constructed grouped these 23 inbred chicken lines into four different clusters. These results are in accordance with the origin and breeding history of these inbred lines, which indicates that the use of microsatellites for the study of genetic biodiversity is accurate and reliable. In addition, the significance and value of inbred chicken lines in molecular genetic research is discussed.  相似文献   

18.
A characterization of cell lines that we derived from morulae (three lines), blastocysts (two lines), and the inner cell mass (ICM) is given. The karyotype of all the lines was normal; the genotype of four lines was XX, and four lines were genotypically XY. The pluripotencies and commitment status of the derived lines were estimated. First, there were not less than two-thirds of cells in the populations of the lines derived from morulae and the lCM with both Xs active; 70–100% of cells of the blastocyst-derived lines had one of the Xs in an inactive state. The activity of glucose-6-phosphate dehydrogenase (G6PD) in the lines (genotype XX) derived from morulae and ICM was found to be twofold higher than in lines with genotype XY, and G6PD activity was the same in the blastocyst-derived XX lines and XY lines. Second, when injected intraperitoneally into athymic mice, morulae- and ICM-derived cells gave rise to simple and complex embryoid bodies (EB) resembling to typical “cystic” mouse EBs. Third, when injected subcutaneously to athymic mice, the ICM- or morula-derived cells gave rise to typical teratomas containing derivatives of the three germ layers and components of organogenesis. Comparisons of cell lines of different derivations demonstrated that the pluripotencies of the ES cells derived from morulae or the ICM are higher than those of blastocyst derivation. © 1993 Wiley-Liss, Inc.  相似文献   

19.
20.
Cloned simian virus 40 (SV40)-transformed human breast epithelial cell lines can differentiate to myoepithelial-like cells, and these can be isolated as clonal cell lines. Immunofluorescent and immunocytochemical analysis of such cell lines growing on plastic surfaces, collagen gels, and as tumor-nodules in nude mice indicate that all the cell lines produce SV40 large T antigen, but that the production of this antigen is qualitatively increased in the myoepithelial-like cells and cell lines. The myoepithelial-like cell lines produce 4-6 times more immunoprecipitable large T antigen than the parental epithelial cells. The amount of mRNA for large T antigen is also increased by 3.5-5-fold in the myoepithelial-like cell lines when analysed by dot-blot or by Northern hybridisations. Thus, differentiation along the myoepithelial-like cell pathway is associated in these SV40-transformed cells with increased expression of the viral large T antigen. It is suggested that immortalization of primary breast epithelial cell cultures may be, in part, due to the expression of large T antigen preventing processes of terminal keratinization.  相似文献   

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