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1.
R. J. Kemble 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(3):364-370
Summary An assay is described whereby Eco RI restriction fragment length polymorphisms of mitochondrial and chloroplast DNAs can definitively identify cytoplasms of interest in Brassica crop development. Restrictable mitochondrial and chloroplast DNA is extracted from as little as 2–3 g and 0.5 g leaf tissue, respectively, and the donor plants are able to continue to develop in a normal manner. An unknown cytoplasm can be identified in three days, which is a considerable saving in time and labor compared to the several years required by traditional methods. The assay is very inexpensive and should be established as a routine procedure in laboratories involved in sexual or somatic Brassica hybrid production. 相似文献
2.
《Bioorganic & medicinal chemistry》2016,24(4):886-893
In order to search for novel multifunctional anti-Alzheimer agents, a series of ferulic acid–carbazole hybrid compounds were designed and synthesized. Ellman’s assay revealed that the hybrid compounds showed moderate to potent inhibitory activity against the cholinesterases. Particularly, the AChE inhibition potency of compound 5k (IC50 1.9 μM) was even 5-fold higher than that of galantamine. In addition, the target compounds showed pronounced antioxidant ability and neuroprotective property, especially against the ROS-induced toxicity. Notably, the neuroprotective effect of 5k was obviously superior to that of the mixture of ferulic acid and carbazole, indicating the therapeutic effect of the hybrid compound is better than the combination administration of the corresponding mixture. 相似文献
3.
Molecular cloning and physical characterization of a Brassica linear mitochondrial plasmid 总被引:2,自引:0,他引:2
Summary A linear mitochondrial plasmid reported to be associated with cytoplasmic male sterility in the genus Brassica was analyzed. A protein was found to be associated with the 5 ends of the plasmid. The entire plasmid was cloned by the homopolymer tailing technique via free hydroxyl groups present at its 3 ends. DNA sequence analysis of the cloned plasmid revealed a perfect terminal inverted repeat of 325 base pairs. Southern hybridization and restriction enzyme mapping analysis confirmed colinearity of the native plasmid and the clone, which showed significant homology with organelle DNA but not with nuclear DNA. Under high-stringency hybridization conditions, an internal 4.6 kb fragment of the 11.5 kb plasmid hybridized to the main mitochondrial genome in several species. Although the hybridization signal was weaker, the chloroplast genome also showed homology to the mitochondrial plasmid. The plasmid was undetectable at a molar ratio of less than 1/10 000 of the main mitochondrial genome in some lines of Brassica and Raphanus that contain the Ogura male sterile cytoplasm (cms). The absence of the plasmid in these sterile lines demonstrates that the plasmid is not required for the expression and maternal inheritance of male sterility. 相似文献
4.
Summary When Drosophila melanogaster males coming from a class of strains known as inducer are crossed with females from the complementary class (reactive), a quite specific kind of sterility is observed in the F1 female progeny (denoted SF). The inducer chromosomes differ from the reactive chromosomes by the presence of a transposable element (called the I factor) that is responsible for the induction of this dysgenic symptom. In the germ line of dysgenic females, up to 100% of the reactive chromosomes may be contaminated, i.e. they acquire I factor(s) owing to very frequent replicative transpositions. A contaminated reactive stock was obtained by reconstructing the reactive genotype in the offspring of SF females and its kinetics of invasion by I elements was followed in the successive inbred dysgenic generations. The results show that the mean copy number of I elements increased very quickly up to the level of inducer strains and then stayed in equilibrium even though the dysgenic state was perpetuated by selection for SF sterility at every generation. The possible mechanisms of this copy number limitation are discussed. 相似文献
5.
B. S. Landry R. Kesseli Hei Leung R. W. Michelmore 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(5):646-653
Summary Five accessions of members of the C group of male sterile maize cytoplasms (BB, C, ES, PR, and RB) in two nuclear backgrounds (A619 and A632) were examined to elucidate the nature of mitochondrial genome diversity within a related group of cytoplasms. Cosmid and plasmid clones carrying single copy and recombinationally active sequences from N and S cytoplasms of maize were used as probes. Although restriction patterns are quite similar, each of the five could be discriminated by evidence of sequence duplication and recombination, deletion of recombinationally active sequences of N, normal cytoplasm, population of mini-circular DNAs, and by restriction patterns. Each member of the group carried a 1,913 bp minicircular mtDNA, while all entries but RB carried a 1,445 bp minicircular mtDNA. Members of the C group clearly are not molecularly identical; evolution of the group included principal genome reorganization involving sequence duplication/deletion events, apparently independent of the cms trait.Cooperative Investigations of Agricultural Research Service, U.S. Department of Agriculture, and Institute of Food and Agricultural Sciences, University of FloridaMention of trademark, proprietary product, or vendor does not constitute a guarantee of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that may also be suitable 相似文献
6.
Gynodioecy, the coexistence of hermaphrodites and male steriles, is frequent in populations of Plantago lanceolata L. A condition for the maintenance of gynodioecy in an obligatory outbreeding species like this is an increase in female fitness in male steriles compared with hermaphrodites. One of the possible underlying mechanisms, a lower cyanide-resistant respiration in male steriles, which could lead to a higher metabolic efficiency, was investigated. For the experiments adult plants were used, because the effects which compensate for male sterility have been found in characters like seed production and longevity. No general correlation between sex phenotype and cyanide-resistant respiration capacity, or with any other respiration component, was found. Only in a single cross a strong correlation between cyanide-resistant respiration activity and sex phenotype was established, male steriles possessing the higher activity. The conclusion from these experiments is that there is no pleiotropic relationship between respiration levels and sex phenotype. The strongly significant correlation mentioned is ascribed to chromosomal linkage. 相似文献
7.
M. Stine B. B. Sears D. E. Keathley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(6):768-774
Summary Chloroplast DNA (cpDNA) was purified from blue spruce (Picea pungens Engelm.) and white spruce [P. glauca (Moench) Voss], and was digested with several different restriction endonucleases. Restriction fragment length polymorphisms (RFLPs) were identified that differentiated the cpDNA of both species. Intraspecific conservation of the RFLPs that differentiated each species was confirmed by examining trees from across the natural range of each species. Ten F1 hybrids were examined, and the cpDNA from each showed the banding pattern of the paternal species. Cloned Petunia cpDNA containing part of the rbcL gene hybridized to polymorphic bands, while a cloned maize mtDNA probe of the coxII gene failed to hybridize to any band. 相似文献
8.
A. G. L. de Courcel F. Vedel J. M. Boussac 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,77(6):793-798
Summary Mitochondrial and chloroplast DNA was isolated from fertile and cytoplasmic male sterile cultivars of cultivated onions. Restriction fragment length polymorphism led to the distinction between cytoplasms S and M. Mitochondrial DNA patterns from S cytoplasms appeared dentical and characterized mostly male sterile lines. An open-pollinated variety was found to bear this cytoplasm and thought to be the origin of S types. Mitochondrial DNA patterns from M cytoplasms were subdivided into four types, M1 and M2 corresponding to normal N cytoplasm, M3 and M4 probably corresponding to T cytoplasms. S and M cytoplasms were also distinguished by chloroplast DNA restriction patterns. Our results confirm previous genetic distinction between S, N and T cytoplasms. 相似文献
9.
Use of tissue culture to bypass wheat hybrid necrosis 总被引:1,自引:0,他引:1
Z. Chen D. A. Evans A. Vasconcelos 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(1):57-60
Summary Hybrid necrosis in wheat is a barrier to gene transfer in wheat breeding practice. It is based on two complementary genes, Ne1 and Ne2. Recovery mutants (Re1, Re2 and Re3) which can grow to maturity were recovered from immature embryo cultures of necrotic hybrids between T. aestivum and T. durum. Cytological observation demonstrated that Re1 had 34 chromosomes instead of 35. This indicated that one of the chromosomes carrying the Ne genes was lost. Genetic study suggested that for Re1, the lost chromosome was chromosome 5B of the durum parental line. Re mutants are male sterile but can be maintained through a young ear culture method. Re mutants could be successfully pollinated by either parental line and the BC1 progeny is partially fertile. Re mutants were repeatedly induced in about 1% of the regenerated plants from immature embryo culture. This technique provides a practical way to bypass hybrid necrosis. 相似文献
10.
P. S. Jourdan E. D. Earle M. A. Mutschler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(3):445-455
Summary Fusion of leaf protoplasts from an inbred line of Brassica oleracea ssp. botrytis (cauliflower, n=9) carrying the Ogura (R1) male sterile cytoplasm with hypocotyl protoplasts of B. campestris ssp. oleifera (cv Candle, n=10) carrying an atrazine-resistant (ATR) cytoplasm resulted in the production of synthetic B. napus (n=19). Thirty-four somatic hybrids were produced; they were characterized for morphology, phosphoglucose isomerase isoenzymes, ribosomal DNA hybridization patterns, chromosome numbers, and organelle composition. All somatic hybrids carried atrazine-resistant chloroplasts derived from B. campestris. The mitochondrial genomes in 19 hybrids were examined by restriction endonuclease and Southern blot analyses. Twelve of the 19 hybrids contained mitochondria showing novel DNA restriction patterns; of these 12 hybrids, 5 were male sterile and 7 were male fertile. The remaining hybrids contained mitochondrial DNA that was identical to that of the ATR parent and all were male fertile. 相似文献