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A. S. Kagramanova A. L. Korolev C. Schal D. V. Mukha 《Russian Journal of Genetics》2006,42(4):397-401
Using polymerase chain reaction technique with primers flanking target sites of retrotransposons R1 and R2, integrated copies of these transposable elements were amplified in various cockroach species (Blattodea). It was shown that each species has a unique pattern of “5′-truncated copies” with the definite set of amplified fragments of different lengths. Intraspecies polymorphism was revealed in analysis of German cockroach specimens obtained upon individual mating. This is the first report providing results of identifying, cloning, and sequencing extended fragments (5′-truncated copies) of Blattella germanica R1 and R2 retrotransposons. It may be assumed that patterns of 5′-truncated copies of R1 and R2 elements can be used as markers in population and phylogenetic studies. Moreover, cloned and sequenced fragments will be employed in our further studies for screening of the German cockroach genomic library in order to detect full-length copies in this class transposable elements. 相似文献
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T. V. Kapelinskaya A. S. Kagramanova A. L. Korolev D. V. Mukha 《Russian Journal of Genetics》2011,47(2):129-138
The rDNA locus of insects and other arthropods contains non-LTR retrotransposons (retroposons) that are specifically inserted
into 28S rRNA genes. The most frequent retroposons are R1 and R2, but the mechanism of insertion and the functions of these
mobile elements have not been studied in detail. A clone containing a full-length R1 retroposon copy was isolated from the
cosmid library of Blattella germanica genes and sequenced. The amino acid sequences encoded by ORF1 of the R1 retroposon were subjected to bioinformatic analysis.
It was found that ORF1 of this mobile element encodes a protein (ORF1p) belonging to the superfamily of zinc finger (CCHC)
retroviral nucleocapsid proteins and contains two conserved RRM domains (RNA-recognizing motifs) identified on the basis of
analysis of the secondary structure of this protein. The discovery of RRM domains in ORF1p of R1 retroposons can contribute
to the understanding of the mechanisms of their retrotransposition. We revealed a coiled-coil motif in the N-terminal region
of R1 ORF1p, which is similar to the coiled-coil domain involved in homo- or heteromultimerization of proteins and in protein-protein
interactions. The domain organization of homologous Gag-like proteins of retroposons in some insects and fungi was found to
be similar to the structure established for R1 ORF1p of B. germanica. 相似文献
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O. V. Gnedenko A. S. Ivanov E. O. Yablokov S. A. Usanov D. V. Mukha G. V. Sergeev A. V. Kuzikov N. E. Moskaleva T. V. Bulko V. V. Shumyantseva A. I. Archakov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2014,8(3):231-236
Molecular interactions between protein partners of the monooxygenase system involved in drug biotransformation (cytochromes P450 3A4, 3A5 and cytochrome b 5) have been investigated. Human cytochromes P450 3A4 and 3A5 (CYP3A4 and CYP3A5) form complexes with various forms of cytochrome b 5, including microsomal (b 5 mc) and mitochondrial (b 5 om) forms of this protein, as well as two chimeric constructs (b 5(om-mc),(b 5(mc-om). Interestingly, significant differences were observed only during interactions with b 5 om. Electroanalytical characteristics of electrodes with immobilized hemoproteins have been determined for CYP3A4, CYP3A5, b 5 mc, b 5 om, b 5 mc(om-mc), and b 5 mc(mc-om). The electrochemical analysis revealed that these proteins are characterized by close reduction potentials ranged from ?0.435 V to ?0.350 V (vs. Ag/AgCl). Cytochrome b 5 mc stimulated the electrocatalytic activity of CYP3A4. 相似文献
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A new Blattella germanica densovirus (BgDNV, Parvoviridae: Densovirinae, Densovirus) was found. Virus DNA and cockroach tissues infected with BgDNV were examined by electron microscopy. Virus particles about 20 nm in diameter were observed both in the nucleus and in the cytoplasm of infected cells. Virus DNA proved to be a linear molecule sized about 1.2 microns. The complete BgDNV genome was sequenced and analyzed. Five ORF were detected: two coded for structural capsid proteins and were on one DNA strand, and three coded for regulatory proteins and were on the other strand. Potential promoters and polyadenylation signals were identified. Structural analysis was performed for terminal inverted repeats containing extended palindromes. The genome structure of BgDNV was compared with that of other Parvoviridae. 相似文献
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The timing of alpha-gustducin expression during cell renewal in rat vallate taste buds 总被引:2,自引:2,他引:0
The G protein subunit alpha-gustducin is expressed in a subset of light
(Type II) but not in dark (Type I) cells in rat vallate taste buds. The
thymidine analogue 5-bromo-2'-deoxyuridine (BrdU) is incorporated into DNA
during the S-phase of the cell cycle and can be used to determine the time
of origin of a cell. In this study, 31 rats were injected with BrdU (50
mg/kg i.p.) and perfused at various times, from 2.5 to 10.5 days, following
BrdU administration. Vallate papillae were embedded in polyester wax, cut
into 4 microm transverse sections, and characterized with antibodies to
BrdU and alpha-gustducin. Sections were processed for indirect
immunofluorescence or with an immunoperoxidase procedure. From
immunoperoxidase material on 21 rats, counts of alpha-gustducin- and
BrdU-labeled cells were obtained from 300-800 taste bud profiles at each
survival time; a total of 4122 taste bud profiles were examined. Cells with
nuclei immunoreactive for BrdU occurred within the taste buds at 2.5 days
and double-labeled cells were clearly evident at 3.5 days; a small number
of double-labeled cells were seen as early as 2.5 days. Double-labeled
cells reached a peak at 6.5 days and did not decline significantly by 10.5
days. Cells labeled for BrdU but not alpha-gustducin peaked at 5.5 days and
showed a significant decline by 8.5 days. These latter cells included light
cells not expressing alpha- gustducin and dark cells, which have previously
been shown to have a shorter life span than light cells. These data suggest
that expression of alpha-gustducin appears very early in a cell's life span
and that these cells are longer lived than many of the cells that do not
express this G protein.
相似文献
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Tonic GABAergic inhibition of taste-responsive neurons in the nucleus of the solitary tract 总被引:4,自引:1,他引:3
The effects of gamma-aminobutyric acid (GABA) and the GABAA receptor
antagonist bicuculline methiodide (BICM) on the activity of taste-
responsive neurons in the nucleus of the solitary tract (NST) were examined
electrophysiologically in urethane-anesthetized hamsters. Single neurons in
the NST were recorded extracellularly and drugs (21 nl) were microinjected
into the vicinity of the cell via a multibarrel pipette. The response of
each cell was recorded to lingual stimulation with 0.032 M NaCl, 0.032 M
sucrose, 0.0032 M citric acid and 0.032 M quinine hydrochloride (QHCl).
Forty-six neurons were tested for the effects of GABA; the activity of 29
cells (63%) was inhibited by 5 mM GABA. Whether activity was elicited in
these cells by repetitive anodal current stimulation (25 microA, 0.5 s, 0.1
Hz) of the tongue (n = 13 cells) or the cells were spontaneously active (n
= 13 cells), GABA produced a dose-dependent (1, 2 and 5 mM) decrement in
activity. Forty- seven NST neurons were tested for the effects of BICM on
their responses to chemical stimulation of the tongue; the responses of 28
cells (60%) were enhanced by 10 mM BICM. The gustatory responses of 26 of
these cells were tested with three concentrations (0.2, 2 and 10 mM) of
BICM, which produced a dose-dependent increase in both spontaneous activity
and taste-evoked responses. Nine of these neurons were sucrose- best, seven
were NaCl-best, eight were acid-best and two responded best to QHCl. The
responses to all four tastants were enhanced, with no difference among
neuron types. For 18 cells that were tested with two or more gustatory
stimuli, BICM increased their breadth of responsiveness to their two most
effective stimuli. These data show that approximately 60% of the
taste-responsive neurons in the rostral NST are inhibited by GABA and/or
subject to a tonic inhibitory influence, which is mediated by GABAA
receptors. The modulation of these cells by GABA provides a mechanism by
which the breadth of tuning of the cell can be sharpened. Modulation of
gustatory activity following a number of physiological changes could be
mediated by such a GABAergic circuit.
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