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Sharon A. Boylan Kristin T. Chun Barton A. Edson Chester W. Price 《Molecular & general genetics : MGG》1988,212(2):271-280
Summary The physiological roles of the gene subset defined by early-blocked sporulation mutations (spo0) and their second-site suppressor alleles (rvtA11 and crsA47) remain cryptic for both vegetative and sporulating Bacillus subtilis cells. To test the hypothesis that spo0 gene products affect global regulation, we assayed the levels of carbon- and nitrogen-sensitive enzymes in wild-type and spo0 strains grown in a defined minimal medium containing various carbon and nitrogen sources. All the spo0 mutations (except spo0J) affected both histidase and arabinose isomerase levels in an unexpected way: levels of both carbon-sensitive enzymes were two- to six-fold higher in spo0 strains compared to wild type, when cells were grown on the derepressing carbon sources arabinose or maltose. There was no difference in enzyme levels with glucose-grown cells, nor was there a significant difference in levels of the carbonindependent enzymes glutamine synthetase and glucose-6-phosphate dehydrogenase. This effect was not due to a slower growth rate for the spo0 mutants on the poor carbon and nitrogen sources used. The levels of carbon-sensitive enzymes were not simply correlated with sporulation ability in genetically suppressed spo0 mutants, but the rvtA and crsA suppressors each had such marked effects on wild-type growth and enzyme levels that these results were difficult to interpret. We conclude that directly or indirectly the spo0 mutations, although blocking the sporulation process, increase levels of carbon-sensitive enzymes, possibly at the level of gene expression. 相似文献
3.
A patient with moderate to severe hemophilia B has been found to have a large insertion within his factor IX gene. The site of insertion is located in a DNA segment of approximately 0.8 kb between exon IV and an EcoRI site within intron D. The size of the DNA insertion is approximately 6 kb, and it contains at least two TaqI sites, two EcoRI sites, and one HindIII site. The insert probably originates from outside the FIX gene and does not represent an internal duplication. We propose that this abnormal FIX gene be called FIX El Salvador in recognition of the birthplace of the patient. 相似文献
4.
New common nomenclature for glycoprotein genes of varicella-zoster virus and their glycosylated products. 总被引:21,自引:14,他引:7 下载免费PDF全文
A J Davison C M Edson R W Ellis B Forghani D Gilden C Grose P M Keller A Vafai Z Wroblewska K Yamanishi 《Journal of virology》1986,57(3):1195-1197
The accumulation of recent data concerning the reactivity of monoclonal antibodies with particular varicella-zoster virus (VZV) glycoproteins and the mapping of several of their respective genes on the VZV genome has led to a unified nomenclature for the glycoprotein genes of VZV and their mature glycosylated products. Homologs to herpes simplex virus glycoprotein genes are noted. 相似文献
5.
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Minimizing growth regulators in shoot culture of an endangered plant,Hackelia venusta (Boraginaceae)
John L. Edson Annette D. Leege-Brusven Richard L. Everett David L. Wenny 《In vitro cellular & developmental biology. Plant》1996,32(4):267-271
Summary
Hackelia venusta (Boraginaceae) is an endangered perennial herb endemic to the interior northwestern United States. Because of seed scarcity,
micropropagation (anex situ conservation strategy) could produce true-to-type plantlets suitable for reintroduction. We hypothesized that clones of predetermined
size could be rapidly produced by supplementing multiplication and rooting media with minimal levels of cytokinin and auxin.
Microshoots derived from shoot expants were cultured on Murashige and Skoog (1962) media supplemented with 1% (wt/vol) agar
and 0.0001 to 10 μM benzyladenine. Inverse regression estimates on 3 genotypes predicted that a target of 2.5 axillary microshoots per explant
would require a minimal level of 0.04±0.02 μM benzyladenine. Culture of 25 genotypes with 0.04 μM benzyladenine resulted in an average of 2.3±0.1 axillary microshoots per explant. Elongated microshoots were transferred
to media supplemented with 0.1 to 25 μM indoleacetic acid. Clones rooted from 36% to 100% success after 4 wk in 2.0 μM indoleacetic acid. Plantlets transplantedex vitro with three or more roots survived at 84% versus 46% of plantlets with fewer roots. Up to 84% of the plantlets survived in
a planting trial. The data suggest that shoot culture ofHackelia venusta, with minimal growth regulators, can produce axillary microshoots for reintroduction. 相似文献
7.
Fresh and dry body weights (FW, DW) were greater for adult southern green stink bug,Nezara viridula (L.) than for the brown stink bug,Euschistus heros F. throughout the year in southern Brazil. FemalesN. viridula significantly increased FW and DW in late summer-early autumn, and during mid-spring; femaleE. heros did not show the same rates of increase in FW and DW. FemaleN. viridula were heavier than males, particularly during summer; however, female and maleE. heros were generally similar in weight.E. heros contained significantly greater amounts of lipid thanN. viridula, during mid-autumn to early-spring (April–September). Survivorship (%) and total longevity ofE. heros adults provided water only was greater (34.6–24.6 days, for females and males) than that forN. viridula (14.8–13.0 days); without water and food, longevity was drastically reduced (<7 days) for both species. 相似文献
8.
H Okayama C M Edson M Fukushima K Ueda O Hayaishi 《The Journal of biological chemistry》1977,252(20):7000-7005
Poly(ADP-ribose) synthetase has been purified approximately 5000-fold from rat liver nuclei. The activity of the purified enzyme is absolutely dependent upon the presence of native or synthetic DNA, and the further addition of histone(s) stimulates the activity 3- to 5-fold. When the ADP-ribosylated material synthesized in the absence or presence of various histones is analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the major product in all cases migrates between histones H1 and H3-H2B with the same RF value of 0.58 relative to the marker dye. No ADP-ribose was found to co-electrophorese with any of thehistones. The addition of histones does not affect the chain number of the poly(ADP-ribose) synthesized but does result in an increase in the average chain length of the polymer. In the presence of histones, the Km for NAD+ decreases from 80 micron to 25 micron and the Vmax doubles. These results indicate that, in the purified poly(ADP-ribose) synthetase system, histones are not ADP-robosylated but act as allosteric activators. 相似文献
9.
Epstein-Barr virus membrane antigens: characterization, distribution, and strain differences. 总被引:22,自引:18,他引:4 下载免费PDF全文
The Epstein-Barr virus (EBV)-associated membrane antigen polypeptides (350,000, 220,000, 140,000, and 85,000 daltons) are recognized by a rabbit anti-EBV serum and are present on the plasma membranes of producer cell lines, as we demonstrated previously. In this report, we show that these polypeptides are present on intact virus particles. Subcellular fractionation revealed that these antigens are distributed throughout the cell, except for the 85,000-dalton protein, which was poorly represented in the nuclear fraction. In addition, an EBV-associated protein of 160,000 daltons, which comigrates with a major component of the viral capsid, was detected in the cytoplasmic and nuclear fractions. The immunoprecipitation patterns of 13 different EBV isolates were similar, with two exceptions. First, the 350,000- and 220,000-dalton polypeptides from marmoset cell lines had slightly larger molecular sizes than the corresponding polypeptides from human cell lines. Second, B95-8 virus and B95-8-derived human and marmoset cell lines contained little of the 220,000-dalton protein; however, 883L, the human parent line of B95-8, has a normal amount of the 220,000-dalton protein. Thus, the B95-8 strain of EBV appears to be a structurally defective variant. We have not observed any variation in protein patterns associated with different EBV disease states. The 350,000-, 220,000-, and 85,000-dalton polypeptides were shown to be glycoproteins by incorporation of [3H]mannose and [3H]glucosamine and to contain N-asparagine-linked glycosyl groups by their sensitivity to tunicamycin. To simplify future work, the following nomenclature for these EBV-associated polypeptides is suggested: 350,000 (gp350), 220,000 (gp220), 160,000 (p160), 140,000 (p140), and 85,000 (gp85). 相似文献
10.
J. Edson Pontes James M. Pierce Jr. Byung-Kil Choe Noel R. Rose 《In vitro cellular & developmental biology. Plant》1979,15(7):469-472
Summary Studies of acid phosphates produced by cell lines MA 160 and EB 33 demonstrated immunochemically their prostatic origin. MA
160 and EB 33, rather than being HeLa contaminants, may be hybrids of prostatic epithelial and HeLa cells or true prostatic
cell lines with chromosomal changes common to all long-term cultivated cell lines.
This research was supported by NIH (Cancer) Research Grants Nos. 18748 and 16426; and Detroit General Hospital Research Corporation. 相似文献