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A. P. Kotnova N. N. Karpova M. A. Feoktistova N. V. Lyubomirskaya A. I. Kim Yu. V. Ilyin 《Russian Journal of Genetics》2005,41(1):17-22
A search for noncanonical variants of the gypsy retrotransposon ( MDG4 ) in the genome of the Drosophila melanogaster strain G32 led to the cloning of four copies of the poorly studied 7411-bp gtwin element. Sequence analysis showed that gtwin belongs to a family of endogeneous retroviruses, which are widespread in the Drosophila genome and have recently been termed insect erantiviruses. The gtwin retrotransposon is evolutionarily closest to MDG4, as evident from a good alignment of their nucleotide sequences including ORF2 (the pol gene) and ORF3 (the env gene), as well as the amino acid sequences of their protein products. These regions showed more than 75% homology. The distribution of gtwin was studied in several strains of the genus Drosophila. While strain G32 contained more than 20 copies of the element, ten other D. melanogaster strains carried gtwin in two to six copies per genome. The gtwin element was not detected in D. Hydei or D. Virilis. Comparison of the cloned gtwin sequences with the gtwin sequence available from the D. melanogaster genome database showed that the two variants of the mobile element differ by the presence or absence of a stop codon in the central region of ORF3. Its absence from the gtwin copies cloned from the strain G32 may indicate an association between the functional state of ORF3 and amplification of the element.Translated from Genetika, Vol. 41, No. 1, 2005, pp. 23–29.Original Russian Text Copyright © 2005 by Kotnova, Karpova, Feoktistova, Lyubomirskaya, Kim, Ilyin. 相似文献
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THERE are two principal groups of theories of ageing—those which hold that random cell damage is chiefly responsible for the events characteristic of ageing, which culminate in death and those which hold that ageing and death are genetically controlled. It is too soon to decide between these points of view and in any case Bullough1 has shown that they are not mutually exclusive. So far experiments to test the random error theories of ageing, involving exposure of organisms to unnaturally large or even small amounts of agents such as X-rays and mutagenic agents (for reviews, see refs. 2 and 3), have been controversial and inconclusive. 相似文献
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Drosophila lamin C (LamC) is a developmentally regulated component of the nuclear lamina. The lamC gene is situated in the fifth intron of the essential gene tout velu (ttv). We carried out genetic analysis of lamC during development. Phenotypic analyses of RNAi-mediated downregulation of lamC expression as well as targeted misexpression of lamin C suggest a role for lamC in cell survival. Of particular interest in the context of laminopathies is the caspase-dependent apoptosis induced by the
overexpression of lamin C. Interestingly, misexpression of lamin C in the central nervous system, where it is not normally
expressed, did not affect organization of the nuclear lamina. lamC mutant alleles suppressed position effect variegation normally displayed at near-centromeric and telomeric regions. Further,
both downregulation and misexpression of lamin C affected the distribution of heterochromatin protein 1. Our results suggest
that Drosophila lamC has a tissue-specific role during development and is required for chromatin organization. 相似文献
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There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
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N. Yu. Markelova 《Microbiology》2010,79(6):777-779
Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached
to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection
and public health is discussed. 相似文献
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Esterases are known for their involvement in several physiological processes and high degree of polymorphism, in many organisms.
Such polymorphism has been used to characterize species and species groups and to study genetic changes occurred in their
evolutionary history. In the present study, the esterase patterns of 19 strains from 10 species representative of the five
subgroups of the saltans species group were analyzed using polyacrylamide gel electrophoresis and α- and β- naphthyl acetates as substrates. Fifty-one
esterase bands were detected and classified as 31 α-esterases, 18 β-esterases and two α/β-esterases. On the basis of the inhibition
patterns using Malathion and eserine sulfate, 34 bands were classified as carboxylesterases, 14 as acethylesterases and three
as cholinesterases. Ten gene loci were tentatively established on the basis of data on band position in the gel, substrate
preference and inhibition pattern. Twenty bands were species-specific, the remaining being shared by species from the same
or different subgroups. Bands detected exclusively in males and bands with a different frequency or degree of expression between
sexes were also detected. In the gels prepared for analysis of gene expression in the body parts (head, thorax and abdomen),
the degree of expression of the β-esterases was higher in the thorax, while the α-esterases were expressed predominantly in
the abdomen and thorax. A global view of the data available at present on the esterases of the species from the saltans group and their degree of polymorphism are presented, as well as the possibility of using some β-esterases, because of their
characteristics in the gels, as markers for species identification. 相似文献
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O. V. Golovanova V. I. Konenkov A. V. Shevchenko M. V. Smolnikova 《Russian Journal of Genetics》2009,45(8):981-986
Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were
investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined. 相似文献
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K. I. Kirsanov E. A. Lesovaya R. A. Sidorov G. A. Belitsky M. G. Yakubovskaya 《Russian Journal of Genetics》2011,47(4):409-416
The test for somatic mutagenesis and recombination in Drosophila is one of the widely used approaches for determination of possible carcinogenic effects of chemical compounds. The use of
heterozygotes for mutant tumor suppressor gene wts enables more direct evaluation of the blastomogenic effects of chemical compounds, by tumor formation in the adult flies.
This study presents evaluation of the SMART effectiveness upon the use of Drosophila heterozygotes for the wts
P4
gene, first included into the test system. The increase of the test resolution capacity compared to the literature data for
the wts
P2
allele was observed. Using wts
P4
heterozygotes, a total of 20 carcinogenic compounds, and their slightly carcinogenic and non-carcinogenic analogs were tested.
Specificity of the method was about 100%, and sensitivity depended on the type of the agent tested. The latter was absolute
for the direct action carcinogens, with respect to carcinogens, requiring the metabolic activation. The sensitivity was elective
and was limited by the presence of the enzymes capable of activating of these compounds. To increase the test sensitivity,
the RNA interference-mediated silencing of the Drosophila p53 functional activity was successfully applied. Moreover, the frequency of wts tumor induction considerably increased both in spontaneous and induced mutagenesis conditions. 相似文献
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B. F. Chadov N. B. Fedorova E. V. Chadova E. A. Khotskina M. P. Moshkin D. V. Petrovski 《Russian Journal of Genetics》2010,46(9):1062-1066
Conditional dominant lethals (CDL) represent a special class of genetic mutations observed in Drosophila. Mutation manifests as a dominant lethal in one genotype, but lethality is not expressed in another genotype. CDL mutants
exhibit a set of traits discriminating them from classic mutations. We observed unusually high mobility of flies and high
sexual activity of males carrying these mutations. We used special tests for evaluation of energy metabolism of CDL mutants.
Indirect calorimetry (CO2 excretion measurement) has been used for estimation of energy exchange in four mutant and two control fly lines. A special
device has been used for evaluation of locomotor activity of these fly lines. Energy exchange and locomotor activity in CDL
mutants were significantly higher than in control lines. We conclude that some genetic mutations are capable of increasing
energy dissipation in their carriers. 相似文献
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Quantitative trait loci (QTL) detection was carried out for adventitious rooting and associated propagation traits in a second-generation
outbred Corymbia torelliana × Corymbia citriodora subspecies variegata hybrid family (n = 186). The parental species of this cross are divergent in their capacity to develop roots adventitiously on stem cuttings
and their propensity to form lignotubers. For the ten traits studied, there was one or two QTL detected, with some QTL explaining
large amounts of phenotypic variation (e.g. 66% for one QTL for percentage rooting), suggesting that major effects influence
rooting in this cross. Collocation of QTL for many strongly genetically correlated rooting traits to a single region on linkage
group 12 suggested pleiotropy. A three locus model was most parsimonious for linkage group 12, however, as differences in
QTL position and lower genetic correlations suggested separate loci for each of the traits of shoot production and root initiation.
Species differences were thought to be the major source of phenotypic variation for some rooting rate and root quality traits
because of the major QTL effects and up to 59-fold larger homospecific deviations (attributed to species differences) relative
to heterospecific deviations (attributed to standing variation within species) evident at some QTL for these traits. A large
homospecific/heterospecific ratio at major QTL suggested that the gene action evident in one cross may be indicative of gene
action more broadly in hybrids between these species for some traits. 相似文献
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I. Rosario G. Soro S. Déniz O. Ferrer F. Acosta D. Padilla B. Acosta 《Mycopathologia》2010,169(4):315-319
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts
in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of
Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this
disease. 相似文献
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