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951.
Radionov DB Protsenko OV Andriievs'kyĭ OM Tots'kyĭ VM Kucherov VO Kozerets'ka IA 《T?Sitologii?a i genetika》2011,45(3):63-67
The dynamics of allele frequency of the carboxiesterase gene, the frequency of sex-linked lethal mutations, and recombination events in natural populations of Drosophila melanogaster from Odesa were studied. All studied estimates were shown to remain unchanged in June, July, and August during the 2009 collection season. 相似文献
952.
The antimutagenic activities of the oils obtained from leaves and fruits of Fagus orientalis have been shown in experiments with spontaneous and mutagen- and ageing-induced variability. The aberrations of chromosomes in the meristematic cells of the Allium cepa L., Vicia faba L., Triticum aestivum L., and marrow cells of Vistar rats as well as Arabidopsis thaliana gene mutations have been mobilized as experimental tests. 相似文献
953.
Karelov AV Pirko IaV Kozub NA Sozinov IA Pirko NN Litvinenko NA Lyfenko SF Koliuchiĭ VT Blium IaB Cozinov AA 《T?Sitologii?a i genetika》2011,45(5):3-10
The distribution of alleles at the Lr34 locus associated with leaf rust resistance among winter common wheat (Triticum aestivum L.) cultivars of Ukrainian breeding was studied. Co-dominant molecular-genetic marker cssfr5 was used for detection of the allelic condition of the Lr34 locus. The cultivars with detected allele Lr34(+) were identified as potentially "resistant" and the cultivars in which detected allele Lr34(-) were identified as potentially "susceptible". The collection of the cultivars (81 ones), created in the main plant breeding centers of Ukraine was analyzed. The allele Lr34(+) was identified in 44% cultivars. Results were compared with the data about the distribution of the Lr34(+) in cultivars created in different countries. 相似文献
954.
Matveeva NA Kishchenko EM Shakhovskiĭ AM Potrokhov AA Kuchuk NV 《T?Sitologii?a i genetika》2011,45(5):11-16
Transgenic plants were regenerated from Cichorium intybus L. hairy roots transformed with genes of tuberculosis antigenes ESAT6 and Ag85B or human interferon alpha2b. The plant regeneration was light-dependent and occurred on the media without growth regulators. The DNA PCR and RT-PCR analyses have shown the presence and expression both selective and target genes in all root lines and regenerated plants. 相似文献
955.
Grunina AS Rekubratskiĭ AV Tsvetkova LI Barmintseva AE Vasil'eva ED Kovalev KV Poluéktova OG 《Ontogenez》2011,42(2):133-145
Dispermic androgenesis was used to produce, for the first time, an androgenetic progeny of the Siberian sturgeon (Acipenser baerii) and the androgenetic nuclear cytoplasmic hybrids (Siberian sturgeon, A. baerii x Russian sturgeon, A. gueldenstaedtii) using cryopreserved sperm. Microsatellite DNA analysis confirmed exclusively paternal inheritance in the androgenetic progeny of Siberian sturgeon. Heterozygotes for certain microsatellite loci were detected among the androgenetic hybrids, thereby confirming a dispermic nature of androgenesis. According to the data of comparative morphological analysis, the obtained androgenetic hybrid, by the age of 15 months old, was completely identical to the paternal species. Both a female and a male were detected in the androgenetic sturgeon progenies, which is of interest for producing bisexual progenies via androgenesis. The data of this study confirm the feasibility of dispermic androgenesis using cryopreserved sperm to preserve and recover the gene pools of endangered sturgeon species. 相似文献
956.
Living organisms well adapt themselves to changes in the environment and are robust to potential damage such as mutations. The epigenetic mechanism whereby the suppression of phenotypic variation is achieved has been dubbed canalization. This paper summarizes results of research that employed experimental and theoretical approaches to uncover the mechanisms of canalization of variation in expression of segmentation genes. 相似文献
957.
A new mutant, fimbriata petioles (fip), of Arabidopsis thaliana was obtained by chemical mutagenesis. The mutant is characterized by unusual anomalies of floral organs. Clusters of very large cells formed in the distal region of sepals and petals, which created fringed edges of these organs. An analysis of the morphology of the floral organs and leaves of the fip as 1 double mutant revealed a complementary interaction of the ASYMMETRIC LEAVES1 (AS1) and FIMBRIATA PETIOLES (FIP) genes. It was assumed that the FIP gene, together with the AS1 gene, controls cell proliferation, preventing their premature entry into endocycle. 相似文献
958.
Shamraĭ SN 《Zhurnal obshche? biologii》2003,64(3):195-214
Remarkable progress is achieved now in comprehension of mechanisms that determine functioning of genes responsible for plants' phytopathogenic resistance (genes R). Cloning of great number of Monocotyledones and Dicotyledones resistance genes show that most of proteins coded by these genes have conserved amino-acid motives, which show high homology to amino-acid motives of proteins with well-designated function. Common structures for most proteins produced by genes R include nucleotide-blinding site (NBS), leucine-rich repeat (LRR), site containing homology with the cytoplasmic domains of the Drosophila Toll protein and the mammalian interleukin-1 receptor (TIR), coiled-coil structure (CC), transmembrane domain (TM), and serine/threonine proteinkinase domain (PK). They are combined within the basic classes of resistance genes proteins as follows: TIR-NBS-LRR, CC-NBS-LLRR, NBS-LRR, PK, TM-CC, LRR-TM, LRR-TM-PK. The domains of proteins produced by plant resistance genes cause specific recognition of avirulence genes products and activate signaling cascade, which gives rise to resistance reaction. Some classes of plant resistance genes probably have the same evolutionary origin as the genes that control the innate immunity of ancient animals. The evolution of plant R genes proceeds primarily by duplication and equal or unequal meiotic recombination. The research on genes R functioning besides its theoretical value is a matter of considerable practical interest for construction of plant genotypes resistant against harmful organisms. The progress in comprehension of mechanisms responsible for specificity of avirulence determinants in phytopathogenic organisms recognition makes possible the creation of artificial resistance genes. 相似文献
959.
Molotkov MV Graĭfer DM Popugaeva EA Bulygin KN Meshchaninova MI Ven'iaminova AG Karpova GG 《Bioorganicheskaia khimiia》2007,33(4):431-441
The protein environment of mRNA 3' of the A-site codon (the decoding site) in the human 80S ribosome was studied using a set of oligoribonucleotide derivatives bearing a UUU triplet at the 5'-end and a perfluoroarylazide group at one of the nucleotide residues at the 3'-end of this triplet. Analogues of mRNA were phased into the ribosome using binding at the tRNAPhe P-site, which recognizes the UUU codon. Mild UV irradiation of ribosome complexes with tRNAPhe and mRNA analogues resulted in the predominant crosslinking of the analogues with the 40S subunit components, mainly with proteins and, to a lesser extent, with rRNA. Among the 40S subunit ribosomal proteins, the S3 protein was the main target for modification in all cases. In addition, minor crosslinking with the S2 protein was observed. The crosslinking with the S3 and S2 proteins occurred both in triple complexes and in the absence of tRNA. Within triple complexes, crosslinking with S15 protein was also found, its efficiency considerably falling when the modified nucleotide was moved from positions +5 to +12 relative to the first codon nucleotide in the P-site. In some cases, crosslinking with the S30 protein was observed, it was most efficient for the derivative containing a photoreactive group at the +7 adenosine residue. The results indicate that the S3 protein in the human ribosome plays a key role in the formation of the mRNA binding site 3' of the codon in the decoding site. 相似文献
960.
The effect of carbonate concentration, pH of the medium, and illumination intensity on the major physiological characteristics (growth rate and the intensities of CO2 assimilation and oxygen photoproduction) of the natronophilic cyanobacterium Euhalothece sp. Z-M001 have been studied. It was established that the investigated microorganism has at least two transport systems (TS) for CO2, which differ in both the pH optimum and substrate affinity: TS I has a pH, 9.4-9.5 and a K(S) 0.5 of 13-17 mM, whereas TS II has a pH(opt) 9.9-10.2 and a K(S) 0.5 of 600-800 mM. The substrate affinity of these transport systems is several orders of magnitude lower than the substrate affinity of the transport systems of freshwater cyanobacteria. It is suggested that they are unique for extremely alkaliphilic cyanobacteria and reflect their adaptation to the seasonal cycles of the lake hydrochemistry. 相似文献