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101.
B. F. Chadov E. V. Chadova S. A. Kopyl E. A. Khotskina N. B. Fedorova 《Russian Journal of Genetics》2004,40(3):271-281
We studied facultative dominant lethal mutations obtained earlier inDrosophila melanogaster. In some genotypes, these mutations were expressed as lethals, but in other genotypes they lacked this expression. The mutations were maintained in the following cultures: (1) females Muller-5 heterozygous for the mutation; (2) males crossed to attached-Xfemales; and (3) females and males homozygous for the mutation. During culturing, many mutations were found to give rise to phenotypically abnormal progeny. Generally, these abnormalities were morphoses involving various body parts; they were mostly asymmetric and nonheritable. Maternal and paternal effects in the formation of morphoses were observed. In four cases, dimorphic mutations were recorded: a female homozygous for the mutation had mutant phenotype whereas its male counterpart was phenotypically normal. The mutations were recessive with regard to the norm. New phenotypes behaving as mutations with incomplete penetrance arose during culturing. In cultures of mutant homozygotes phenocopies would appear en masse; they would persist for one or two generations and disappear. One wave of phenocopies succeeded another. Visible phenotypes appeared, which further behaved as ordinary recessive mutations. We concluded that these visible manifestations are characteristic for regulatory mutations controlling ontogeny. Their appearance is explained by the activation of new regulatory scenarios caused by blocking standard regulatory pathways. 相似文献
102.
Fedorova S. A. Bermisheva M. A. Villems R. Maksimova N. R. Khusnutdinova E. K. 《Molecular Biology》2003,37(4):544-553
To study the mitochondrial gene pool structure in Yakuts, polymorphism of mtDNA hypervariable segment I (16,024–16,390) was analyzed in 191 people sampled from the indigenous population of the Sakha Republic. In total, 67 haplotypes of 14 haplogroups were detected. Most (91.6%) haplotypes belonged to haplogroups A, B, C, D, F, G, M*, and Y, which are specific for East Eurasian ethnic groups; 8.4% haplotypes represented Caucasian haplogroups H, HV1, J, T, U, and W. A high frequency of mtDNA types belonging to Asian supercluster M was peculiar for Yakuts: mtDNA types belonging to haplogroup C, D, or G and undifferentiated mtDNA types of haplogroup M (M*) accounted for 81% of all haplotypes. The highest diversity was observed for haplogroups C and D, which comprised respectively 22 (44%) and 18 (30%) haplotypes. Yakuts showed the lowest genetic diversity (H = 0.964) among all Turkic ethnic groups. Phylogenetic analysis testified to common genetic substrate of Yakuts, Mongols, and Central Asian (Kazakh, Kyrgyz, Uighur) populations. Yakuts proved to share 21 (55.5%) mtDNA haplotypes with the Central Asian ethnic groups and Mongols. Comparisons with modern Paleoasian populations (Chukcha, Itelmen, Koryaks) revealed three (8.9%) haplotypes common for Yakuts and Koryaks. The results of mtDNA analysis disagree with the hypothesis of an appreciable Paleoasian contribution to the modern Yakut gene pool. 相似文献
103.
T M Fedorova V P Miakisheva S P Grabarev L N Ryskukova 《Ukrainski? biokhimicheski? zhurnal》1980,52(3):369-374
A mathematical model of acid-soluble DNA formation under the effect of DNase I was developed. The data from the kinetic analysis suggest that at the stage of 10-60% solubilization the number of breaks in DNA single strands seem to be linearly dependent on the increment of acid-soluble DNA. This stage of acid-soluble DNA formation may be interpreted in terms of the monomolecular (pseudomonomolecular) reaction. 相似文献
104.
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107.
The antigenic properties of rat brain and liver chromatin were studied under conditions of prolonged adaptation to hypoxia. The results obtained indicate the increase in the accessibility of the HMG proteins antigenic determinants in rat brain chromatin. 相似文献
108.
S V Usova T S Fedorova Iu V Fedorov N B Al'bitskaia 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1984,(12):89-90
Materials on the study of relationship between the activity of immunoreactive insulin and the degree of an increase in the level of anti-influenza antibodies, induced by vaccine strains, are presented. A short-term decrease in the activity of insulin, more pronounced in donors immunized with adsorbed chemical influenza vaccine, and an increase in the antibody level, mainly in the group of donors receiving killed influenza vaccine, have been noted. 相似文献
109.
Adriana Vela Olga Fedorova Steve C. Ding Anna Marie Pyle 《The Journal of biological chemistry》2012,287(51):42564-42573
RIG-I is a cytoplasmic surveillance protein that contributes to the earliest stages of the vertebrate innate immune response. The protein specifically recognizes 5′-triphosphorylated RNA structures that are released into the cell by viruses, such as influenza and hepatitis C. To understand the energetic basis for viral RNA recognition by RIG-I, we studied the binding of RIG-I domain variants to a family of dsRNA ligands. Thermodynamic analysis revealed that the isolated RIG-I domains each make important contributions to affinity and that they interact using different strategies. Covalent linkage between the domains enhances RNA ligand specificity while reducing overall binding affinity, thereby providing a mechanism for discriminating virus from host RNA. 相似文献
110.
The 34-mer oligodeoxynucleotide was shown to be selectively modified at the G17 position upon photoirradiation in the presence of complementary 17-mer oligodeoxynucleotide bearing Pd(II)-coproporphyrin I covalently linked to the 5'-end phosphate group. 相似文献