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mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
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O. A. Zhuravleva B. V. Morukov A. A. Markin L. V. Vostrikova I. V. Zabolotskaya D. S. Kuzichkin 《Human physiology》2012,38(5):555-557
The content of lipid peroxidation products (diene conjugates, malondialdehyde, Schiff bases) and antioxidant defense system indices (the main lipid antioxidant tocopherol and the level of general antioxidant activity) were measured in the blood serum of five male volunteers aged 25?C40 years in a three-day dry immersion experiment. During the immersion test, no deviations of indices from the background values were found. An increase in the tocopherol concentration within 2 h after the beginning of the experiment was the only exception. A significant increase in the concentration of lipid peroxidation products, particularly, diene conjugates, was observed 2 h after immersion completion during the reconditioning period. However, the tocopherol content was significantly lower than the background values. It is concluded that the subjects?? adaptation to simulated microgravity conditions displays no pronounced stress component, whereas bringing back to normal vital functions after exposure to immersion induces a pronounced stress reaction illustrated by a significant increase in the lipid peroxidation product levels against a background of a decrease in the functional activity of the antioxidant defense system. 相似文献
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Demidyuk I. V. Zabolotskaya M. V. Safina D. R. Kostrov S. V. 《Russian Journal of Bioorganic Chemistry》2003,29(5):418-425
The molecular mechanisms that ensure the stability of proteolytic proteins are discussed. The autolytic pathway of protease degradation is emphasized. Experiments aimed at increasing the thermal stability of thermolysin-like metalloproteases are comprehensively described. 相似文献
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D. S. Kuzichkin A. A. Markin O. A. Juravlyova Z. A. Krivitsina L. V. Vostrikova I. V. Zabolotskaya 《Human physiology》2017,43(1):119-121
The values of 11 diagnostically significant hemostasis system indices were determined during the preflight (30–45 days before start) clinical and physiological examination of 39 cosmonauts aged 35 to 54 years, who were the members of the main and backup crews of missions to the International Space Station (ISS) during the period from 2007 to 2014. Since most of the cosmonauts performed several flights over this period and were repeatedly included in backup crews, each of them underwent examinations one to five times. The reference values were calculated for each of the studied indices. It was found that the reference ranges for the parameters indicative of the integral pro- and anticoagulant and fibrinolytic blood plasma potential were somewhat narrowed and close to the boundaries of general population ranges, which indicates that the cosmonauts had a relatively decreased procoagulant potential and increased regulative potential of the hemostasis system. This was probably due to the criteria of selection, physical training status, and emotional status of crew members during the preflight professional activity, when adaptive changes against stressinducing effects occur in the body. The cosmonauts who underwent strict medical examination may also have some genetic features in which they differ from the general population and which provide higher body resistance and more rapid adaptation processes. 相似文献
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Jane L Wagstaff Jonathan N Pruneda Stefan MV Freund David Komander 《The EMBO journal》2017,36(24):3555-3572
The Ser/Thr protein kinase PINK1 phosphorylates the well‐folded, globular protein ubiquitin (Ub) at a relatively protected site, Ser65. We previously showed that Ser65 phosphorylation results in a conformational change in which Ub adopts a dynamic equilibrium between the known, common Ub conformation and a distinct, second conformation wherein the last β‐strand is retracted to extend the Ser65 loop and shorten the C‐terminal tail. We show using chemical exchange saturation transfer (CEST) nuclear magnetic resonance experiments that a similar, C‐terminally retracted (Ub‐CR) conformation also exists at low population in wild‐type Ub. Point mutations in the moving β5 and neighbouring β‐strands shift the Ub/Ub‐CR equilibrium. This enabled functional studies of the two states, and we show that while the Ub‐CR conformation is defective for conjugation, it demonstrates improved binding to PINK1 through its extended Ser65 loop, and is a superior PINK1 substrate. Together our data suggest that PINK1 utilises a lowly populated yet more suitable Ub‐CR conformation of Ub for efficient phosphorylation. Our findings could be relevant for many kinases that phosphorylate residues in folded protein domains. 相似文献
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A. A. Markin B. V. Morukov O. A. Zhuravleva I. V. Zabolotskaya L. V. Vostrikova N. A. Lyapunova T. G. Tsvetkova 《Human physiology》2010,36(7):861-864
In an experiment with seven-day immersion, blood samples were taken from eight volunteers (21 to 26 years old) seven days
prior to immersion, on days 3 and 7 of immersion and on days 1 and 8 of recovery. Blood serum was analyzed for 38 biochemical
markers of the functional state of the myocardium, skeletal muscles, hepatobiliary system, kidneys, pancreas, gastrointestinal
tract, prostate, and protein-nucleic, carbohydrate, electrolyte, and mineral metabolisms. Seven-day immersion was shown to
alter the biochemical parameters within the range of the physiological norm. The observed changes included lower activities
of enzymes associated with muscular and myocardial constellation, shifts in electrolytes (K, Na, Mg), and an increase in the
biliary function parameters. Increased concentrations of the parameters of lipid metabolism suggest a higher risk of atherogenesis.
Biochemical parameters of bone tissues and erythrocyte activity were practically unchanged. Most of the parameters returned
to the preexperimental values by day 8 of recovery. 相似文献
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