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1.
Summary In an attempt to identify proteins involved in the initiation of DNA replication, we have isolated a series of Saccharomyces cerevisiae mutants in which the function of putative replication origins is affected. The phenotype of these Rar- (regulation of autonomous replication) mutants is to increase the mitotic stability of plasmids whose replication is dependent on weak ARS elements. These mutations are generally recessive and complementation analysis shows that mutations in several genes may improve the ability of weak ARS elements to function. One mutation (rar1-1) also confers temperature-sensitive growth, and thus an essential gene is affected. We have determined the DNA sequence of the RAR1 gene, which reveals an open reading frame for a 48.5 kDa protein. The RAR1 gene is linked to rna1 on chromosome XIII. 相似文献
2.
Edmond A. Goidl Christiane Samarut Ansbert Schneider-Gadicke Neal L. Hochwald G.Jeanette Thorbecke Gregory W. Siskind 《Cellular immunology》1984,85(1):25-33
Using hapten-reversible inhibition of plaque formation as an assay for auto-anti-idiotype antibody (anti-Id) and as a means for following idiotype (Id) expression, we have obtained evidence that following immunization with trinitrophenyl (TNP) conjugates (a) there are differences in Id expression in the anti-TNP antibody response to different TNP conjugates although there is some overlap; (b) different strains, although showing some differences in Id expression, tend to produce cross-reactive Ids, thus no obvious allotype linked inheritance of Id expression is observed in this heterogeneous immune response; (c) the auto-anti-Id produced following immunization with TNP-Brucella abortus or TNP-Ficoll tends to be of the IgG2a and IgG2b isotypes. 相似文献
3.
4.
Studies on the maintenance and expression of cloned DNA fragments in the nuclear genome of the green alga Chlamydomonas Reinhardtii 总被引:3,自引:0,他引:3
Anil Day Robert Debuchy Jeanette van Dillewijn Saul Purton Jean-David Rochaix 《Physiologia plantarum》1990,78(2):254-260
Using a biolistic device built here and based on the principle of the device described by Klein et al. (1987). we have reproducibly obtained transformants of Chlamydomonas reinhardtii . The reproducibility of the method has allowed us to examine the maintenance and expression of cloned DNA fragments introduced into C. Reinhardtii . 相似文献
5.
The effects of light-induced non-photochemical quenching on the minimal Fo, and variable Fv, fluorescence emissions at 690 and 730 nm in leaves were determined. Non-photochemical quenching of Fo, but not Fv, was found to be dependent upon the wavelength of emission, and was greater at 690 nm than at 730 nm. For emission at 730, compared to at 690 nm, approx. 30% of Fo was not affected by non-photochemical quenching processes in leaves of C3 plants; in maize leaves this was found to be approx. 50%. The data indicate that a substantial proportion of the pigments contributing to Fo emission at 730 nm are not quenched by light-induced, non-photochemical quenching processes and that there are large differences in the pigment matrices contributing to Fo and Fv emissions at 730 nm, compared to those at 690 nm. These findings have important implications for the accurate estimation and interpretation of non-photochemical quenching of fluorescence parameters and their use in the calculation of photochemical efficiencies in leaves. Measurements of fluorescence emissions at wavelengths above 700 nm are likely to give rise to significant errors when used for determinations of photochemical and non-photochemical quenching parameters. 相似文献
6.
Sequence and characterization of the Escherichia coli genome between the ndk and gcpE genes 总被引:1,自引:0,他引:1
Abstract The region of the chromosome immediately upstream of the Escherichia coli gene gcpE has been cloned and sequenced. This region contains two functional open reading frames, orf 384 and orf 337, encoding proteins of 43082 and 36189 Da, respectively. Sequencing analysis (this paper) and the isolation of a DNA fragment containing a functional promoter (Talukder, A.A., Yanai, S., and Yamada, M. (1994) Biosci. Biotech. Biochem. 58, 117–120) indicate that orf 337 is in an operon with gcpE . The gene orf 384 is immediately downstream of the gene ndk , which encodes nucleoside diphosphate kinase. 相似文献
7.
Clofentezine resistance in T. urticae was first confirmed in Australia in 1987 after Queensland glasshouse roses had been exposed to 40 applications of clofentezine over a 10 month period. Clofentezine resistance in this strain was extremely high (>2.500x) and conferred high level cross-resistance to the chemically unrelated compound hexythiazox. Clofentezine resistance in T. urticae was detected in pome fruit orchards in the Goulburn Valley, Victoria in 1988 and caused field control failure after 5–6 sprays. Resistance was subsequently detected in Adelaide during 1988 and the Bathurst Orange region, NSW in 1989. Clofentezine and hexythiazox resistance appears particularly stable making it difficult to manage.This work contributes in part for the fulfilment of the requirements of the degree of PhD. at the University of Sydney. 相似文献
8.
Phillip E. Klebba Jeanette M. Rutz Jun Liu Christopher K. Murphy 《Journal of bioenergetics and biomembranes》1993,25(6):603-611
The recent solution of enteric bacterial porin structure, and new insights into the mechanism by which outer membrane receptor proteins recognize and internalize specific ligands, advocates the re-evaluation of TonB-dependent transport physiology. In this minireview we discuss the potential structural features of siderophore receptors and TonB, and use this analysis to evaluate both existing and new models of energy and signal transduction from the inner membrane to the outer membrane of gram-negative bacteria. 相似文献
9.
Markus M. Nöthen Thomas Eggermann Jeanette Erdmann Bernd Eiben Dieter Hofmann Peter Propping Gesa Schwanitz 《Human genetics》1993,92(4):347-349
The parental origin of the extra chromosome in trisomy 18 was traced in 30 informative families using highly polymorphic (CA) repeats mapped on the long arm of chromosome 18. Proband DNA was recovered from slides of chromosome preparations in 28 cases and from paraffin-embedded tissues in two cases. The extra chromosome was found to be of maternal origin in 26 cases (86.7%), and paternal origin in 4 cases (13.3%). 相似文献
10.
Jeanette Møller Nielsen Jürgen Hansen Kirsten Brandt 《Plant Cell, Tissue and Organ Culture》1995,41(2):165-170
Shoots of Miscanthus X ogiformis Honda Giganteus transferred from medium with benzyladenine (BA) to thidiazuron (TDZ) formed significantly more axillary shoots than shoots grown continuously on either medium, or transferred from TDZ to BA. Shoot formation on axillary shoots transferred from BA-containing media to media with kinetin or isopentenyladenine (2iP) or transferred from media with TDZ, kinetin or 2iP to media with BA, corresponded to the number of shoots formed in the previous subculture. Shoot formation on shoots transferred from medium containing BA to media containing combinations of BA and/or TDZ increased with increasing concentrations of TDZ in the first subculture, whereas shoot formation in the second and third subculture depended on the BA concentration. When shoots were transferred from media with BA to media with TDZ, the time for shoot formation, as well as shoot size, indicate that the combined effect of BA and TDZ is expressed only during the early phase of the subculture. The results suggest that adenine- and phenylurea-type cytokinins have a common binding site in the plant cell, and a model is proposed.Abbreviations BA
6-benzyladenine
- CBP
cytokinin-binding protein
- 2iP
isopentenyladenine
- KIN
kinetin
- MS
Murashige & Skoog
- TDZ
thidiazuron 相似文献