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151.
152.
A series of disomic lines of spring wheat Opal selected on the basis of monosomic lines of this cultivar has been studied. The lines have been tested for combining ability, and the heterosis effect has been studied in disomic lines of F1 hybrids obtained by topcrossing. The line have been demonstrated to differ both from one another and from cultivar Opal in the expression of quantitative traits, combining ability, and the degree of heterosis in F1. These data suggest that recombinations accompanying the formation of the monosomic series have changed their genetic program. To test this suggestion, intramolecular heterogeneity of 42-chromosome plants has been analyzed using polymerase chain reaction (PCR) and isoenzyme analysis. The results confirmed the differences at the DNA and protein levels. According to the results of molecular analyses, A-genome lines are the most polymorphic. Strong heterosis effects have been detected in hybrid combinations contributed by D- and B-genome lines, which are characterized by medium and low degrees of molecular genetic polymorphism. Lines that are promising in terms of breeding programs have been identified. 相似文献
153.
A new hypothesis of the genetic regulation of cell differentiation is put forward. The hypothesis is based on the assumption that the diminution and hyper-replication patterns of repetitive nucleotide sequences depend on the differentiation pathways of cells and tissues. 相似文献
154.
Martirosian IA Kan NG Petrosian VG Malysheva DN Trofimova AA Danielian FD Darevskiĭ IS Korochkin LI Ryskov AP Tokarskaia ON 《Genetika》2003,39(2):215-222
Population and family samples of two morphological forms (mutant and normal with respect to dorsal color) of pathogenetic lizard Darevskia armeniaca were examined by means of DNA fingerprinting using M13 mini- and (GATA)n and (TCC)n microsatellite DNA markers. The morphological forms examined were characterized by clonally inherited, species-specific patterns of the DNA markers, which were different from the species-specific DNA fingerprints of the other parthenogenetic species of the genus Darevskia (D. dahli. D. unisexualis, and D. rostombekovi). The mean index of similarity (S) obtained for a sample of 36 individuals from three isolated populations using three types of DNA markers was 0.966. This was similar to the variability level observed in D. dahli (0.962) (P > 0.05), but higher than that in D. unisexualis (0.950) (P < 0.05) and D. rostombekovi (0.875) (P < 0.01). Inheritance of M13 minisatellite and (TCC)n microsatellite DNA markers in the F1 offspring of parthenogenetic lizards was examined. It was shown that variability and clonal diversity of the fingerprint phenotypes observed in the populations and families of D. armeniaca could be at least partly explained by RFLP mutations in microsatellite repeats. 相似文献
155.
Characteristics of radish lines and hybrids from the spectrum of multiple molecular forms of enzymes
We characterized radish lines from a genetic collection on the basis of six enzyme systems, identified genes controlling these enzymes, and examined joint inheritance of some biochemical and morphological traits. 相似文献
156.
157.
Priakhin EA Korytnyĭ VS Akleev AV Krupitskaia LI Anisimova GG Tolstykh EI Triapitsyna GA 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2001,41(2):141-152
The response of bone marrow cells of CBA mice injected with 22.2, 222 and 592 kBq/animal to additional gamma-irradiation (3 Gy) for testing purposes was evaluated using SCG (Comet assay). A decrease in induction of DNA damage right after additional gamma-irradiation was determined. It correlated with bone marrow cell quantity and the tail length before additional gamma-irradiation. The results support the suggestion about the activation of DNA repair in bone marrow cells under exposure to 90Sr in vivo. 相似文献
158.
Li J Sinoway LI 《American journal of physiology. Heart and circulatory physiology》2002,283(6):H2636-H2643
We examined whether ATP stimulation of P2X purinoceptors would raise blood pressure in decerebrate cats. Femoral arterial injection of the P2X receptor agonist alpha,beta-methylene ATP into the blood supply of the triceps surae muscle induced a dose-dependent increase in arterial blood pressure. The maximal increase in mean arterial pressure (MAP) evoked by 0.1, 0.2, and 0.5 mM alpha,beta-methylene ATP (0.5 ml/min injection rate) was 6.2 +/- 2.5, 22.5 +/- 4.4, and 35.2 +/- 3.9 mmHg, respectively. The P2X receptor antagonist pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid (2 mM ia) attenuated the increase in MAP elicited by intra-arterial alpha,beta-methylene ATP (0.5 mM), whereas the P2Y receptor antagonist reactive blue 2 (2 mM ia) did not affect the MAP response to alpha,beta-methylene ATP. In a second group of experiments, we tested the hypothesis that ATP acting through P2X receptors would sensitize muscle afferents and, thereby, augment the blood pressure response to muscle stretch. Two kilograms of muscle stretch evoked a 26.5 +/- 4.3 mmHg increase in MAP. This MAP response was enhanced when 2 mM ATP or 0.1 mM alpha,beta-methylene ATP (0.5 ml/min) was arterially infused 10 min before muscle stretch. Furthermore, this effect of ATP on the pressor response to stretch was attenuated by 2 mM pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid (P < 0.05) but not by the P1 purinoceptor antagonist 8-(p-sulfophenyl)-theophylline (2 mM). These data indicate that activation of ATP-sensitive P2X receptors evokes a skeletal muscle afferent-mediated pressor response and that ATP at relatively low doses enhances the muscle pressor response to stretch via engagement of P2X receptors. 相似文献
159.
Bruijn LI 《BioTechniques》2002,32(5):1112, 1114, 1116 passim
160.
Telomeres, DNA-protein structures, are important elements of the eukaryotic chromosome. Telomeric regions of the majority of higher plants contain heptanucleotides TTTAGGG arranged into a tandem repeat. However, some taxa have no such repeats. These are some species of lilies (Lilium) and onions (Allium). For example, terminal regions of chromosomes of Spanish onion (Allium fistulosum) contain satellite DNA whose unit repeats are 380 bp in length, and the short arm of its chromosome 8 contains rDNA repeats. This study deals with the terminal heterochromatin and organization of the satellite repeat in A. fistulosum. Fluorescent in situ hybridization (FISH) was used to locate the satellite DNA on chromosomes and on extended DNA of A. fistulosum. Nonsatellite DNA was found in the structure of telomeric repeat. Polymerase chain reaction (PCR) and Southern hybridization were used for analysis of terminal heterochromatin. Various rearrangements were found in the satellite repeat. The roles of retrotransposones and microsatellites in the formation of terminal heterochromatin are discussed. 相似文献