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The character of TRD (transmission ratio distortion) was analyzed using the database formed on the basis of the results obtained
for a collection of mice carrying different t haplotypes during 30 years of experimental observations. Quantitative TRD parameters were determined in male mice with T/t
w genotypes from natural populations in crosses with females from laboratory collections. The TRD value varied in the range
from 0.41 to 0.74. The frequencies of t haplotypes in natural Mus musculus populations from different regions (Moscow, Moscow oblast, Tajikistan, Lithuania, and Mongolia) varied from 12% (Tigrovaya
Balka, Tajikistan) to 44% (Ulan-Bator, Mongolia). The factors and mechanisms determining a low frequency of t haplotypes in natural populations are discussed. 相似文献
54.
Ouabain and other cardiotonic steroids (CTS) kill renal epithelial cells from distal tubules (C7-MDCK) via interaction with
Na,K-ATPase but independently of inhibition of Na,K-ATPase-mediated ion fluxes. Recently, we demonstrated that modest intracellular
acidification and inhibition of p38 MAPK suppress death of C7-MDCK cells triggered by ouabain. In the present study we investigate
the mechanism of p38 MAPK activation in renal epithelial cell from distal tubules evoked by cardiotonic steroids. Using Na+/K+ ionophores (monensin, nigericin) and media with different content of monovalent cations, we revealed that p38 MAPK phosphorylation
in ouabain-treated renal epithelial cells is not caused by Na,K-ATPase inhibition and inversion of the [Na+]i/[K+]i ratio. We also demonstrated that attenuation of pH from 7.45 to 6.75 did not alter the level of p38 MAPK phosphorylation
observed in ouabain-treated cells. Inhibitors of PKA, PKC, and PKG as well as protein phosphatases were unable to abolish
p38 MAPK activation triggered by ouabain. Using phosphotyrosine antibodies we did not detect any effect of ouabain on activation
of tyrosine kinases. Thus, our results show that activation of p38 MAPK and cytotoxic action of CTS are independent of intracellular
Na+, K+, and H+ concentrations. The molecular origin of intermediates of death signaling induced by CTS via conformation changes of Na,K-ATPase
with following activation of p38 MAPK should be examined further. 相似文献
55.
Based on materials of trawl studies performed from 1992 to 2002 off the Pacific coast of Kamchatka and the northern Kuril
Islands in the framework of the integrated (VNIRO, KamchatNIRO, Sakh-NIRO) program on the study of fishery resources of the
continental slope, data on the distribution and biology of rock greenling Hexagrammos lagocephalus were analyzed. It was elucidated that this species is extremely eurybathic; the range of its seasonal vertical migrations
embraces depths of 1–2 m in summer, and in the spawning period and up to 665 m in winter. The spatial distribution has a mosaic
pattern, maximum concentrations were recorded at the slope and shelf of the Shumshu Island and the southern extremity of Kamchatka.
The size, weight, and sex composition, and the maturation and feeding of the rock greenling are considered. Maximum fish sizes
in trawl catches are 58 cm and 2.63 kg; sex composition is characterized by the domination of females in all size groups (79%).
The bulk of feeding consisted of Cephalopoda, small crustaceans—Amphipoda and Isopoda—as well as the eggs of fish and Gastropoda.
With an increase in sizes, the greenling passes from feeding on small benthic organisms to larger movable forms. 相似文献
56.
E E Vitiaev Iu L Orlov O V Vishnevski? A S Belenok N A Kolchanov 《Molekuliarnaia biologiia》2001,35(6):952-960
A method is proposed to automatically search for patterns in the mutual location of context signals in regulatory DNA sequences. The procedure is based on the methods of Data Mining and Knowledge Discovery software, implemented in a computer system Gene Discovery. This system was used to study erythroid-specific promoters and promoters of the endocrine-system genes from TRRD. We detected some trends in occurrence and localization of specific oligonucleotide groups. 相似文献
57.
58.
FRIZZY PANICLE Drives Supernumerary Spikelets in Bread Wheat 总被引:1,自引:0,他引:1
Oxana Dobrovolskaya Caroline Pont Richard Sibout Petr Martinek Ekaterina Badaeva Florent Murat Audrey Chosson Nobuyoshi Watanabe Elisa Prat Nadine Gautier Véronique Gautier Charles Poncet Yuriy L. Orlov Alexander A. Krasnikov Hélène Bergès Elena Salina Lyudmila Laikova Jerome Salse 《Plant physiology》2015,167(1):189-199
59.
N. Ya. Orlov T. G. Orlova A. R. Nezvetsky E. A. Burstein H. D. Bartunik 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2011,5(2):121-127
cGMP-Specific phosphodiesterase (PDE6) is the key enzyme of the phototransduction system of vertebrate retinal rod outer segments
(ROS). The properties of PDE in extracts prepared by solubilization of bovine ROS in a high concentration (0.5% w/v) of detergent
n-nonyl-β-D-glucoside (NG) and following centrifugation (ROS-NG) have been studied. Basal PDE activity of the preparations
was low, but it greatly (>50-fold) increased (up to ∼20 μmol cGMP hydrolyzed/min per mg rhodopsin (R)) in the presence of
trypsin. In bleached GTPγS-containing preparations the specific PDE activity was dependent on ROS-NG concentration and was
half-maximal at about 0.8 μM of ROS G protein transducin (Gt). In dark-adapted GTPγS-containing ROS-NG preparations bleaching
of 0.2% of the rhodopsin resulted in half-maximal PDE activation. The same result was obtained when PDE in dark-adapted ROS-NG
preparations was activated by addition of a highly purified bleached rhodopsin solubilized by 0.5% solution of NG. The results
demonstrate that the presence of NG has no significant influence either on the properties of the main ROS phototrans-duction
system elements (R, Gt and PDE) or on the interaction between photoactivated R and Gt and suggest that the detergent NG can
be used for crystallization of the rhodopsin-transducin complex. 相似文献
60.
N Thorin-Trescases S N Orlov S Taurin N O Dulin B G Allen D deBlois J Tremblay A V Pshezhetsky P Hamet 《Canadian journal of physiology and pharmacology》2001,79(6):471-480
The effect of cholera toxin (CTX), an activator of the adenylate cyclase-coupled G protein alpha(s) subunit, was studied on cultured vascular smooth muscle cell (VSMC) proliferation. Continuous exposure (48 h) to CTX as well as 2-min pretreatment of VSMC with CTX led to the same level of cAMP production, inhibition of DNA synthesis, and arrest in the G1 phase without induction of necrosis or apoptosis in VSMC. Protein kinase A (PKA) activity in CTX-pretreated cells was transiently elevated by 3-fold after 3 h of incubation, whereas after 48 h it was reduced by 2-fold compared with baseline values without modulation of the expression of its catalytic alpha subunit. The PKA inhibitors H89 and KT 5720 did not protect VSMC from the antiproliferative effect of CTX. Two-dimensional electrophoresis was used to analyze the influence of CTX on protein phosphorylation. After 3 h of incubation of CTX-pretreated cells, we observed both newly-phosphorylated and dephosphorylated proteins (77 and 50 protein species, respectively). After 24 h of incubation, the number of phosphorylated proteins in CTX-treated cells was decreased to 39, whereas the number of dephosphorylated proteins was increased to 106. In conclusion, brief exposure to CTX leads to full-scale activation of cAMP signaling and evokes VSMC arrest in the G1 phase. 相似文献