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51.
Kayser M Lao O Anslinger K Augustin C Bargel G Edelmann J Elias S Heinrich M Henke J Henke L Hohoff C Illing A Jonkisz A Kuzniar P Lebioda A Lessig R Lewicki S Maciejewska A Monies DM Pawłowski R Poetsch M Schmid D Schmidt U Schneider PM Stradmann-Bellinghausen B Szibor R Wegener R Wozniak M Zoledziewska M Roewer L Dobosz T Ploski R 《Human genetics》2005,117(5):428-443
To test for human population substructure and to investigate human population history we have analysed Y-chromosome diversity using seven microsatellites (Y-STRs) and ten binary markers (Y-SNPs) in samples from eight regionally distributed populations from Poland (n=913) and 11 from Germany (n=1,215). Based on data from both Y-chromosome marker systems, which we found to be highly correlated (r=0.96), and using spatial analysis of the molecular variance (SAMOVA), we revealed statistically significant support for two groups of populations: (1) all Polish populations and (2) all German populations. By means of analysis of the molecular variance (AMOVA) we observed a large and statistically significant proportion of 14% (for Y-SNPs) and 15% (for Y-STRs) of the respective total genetic variation being explained between both countries. The same population differentiation was detected using Monmoniers algorithm, with a resulting genetic border between Poland and Germany that closely resembles the course of the political border between both countries. The observed genetic differentiation was mainly, but not exclusively, due to the frequency distribution of two Y-SNP haplogroups and their associated Y-STR haplotypes: R1a1*, most frequent in Poland, and R1*(xR1a1), most frequent in Germany. We suggest here that the pronounced population differentiation between the two geographically neighbouring countries, Poland and Germany, is the consequence of very recent events in human population history, namely the forced human resettlement of many millions of Germans and Poles during and, especially, shortly after World War II. In addition, our findings have consequences for the forensic application of Y-chromosome markers, strongly supporting the implementation of population substructure into forensic Y chromosome databases, and also for genetic association studies. 相似文献
52.
53.
Kubiński K Domańska K Sajnaga E Mazur E Zieliński R Szyszka R 《Molecular and cellular biochemistry》2007,295(1-2):229-236
Protein kinase CK2 is a highly conserved Ser/Thr protein kinase that is ubiquitous among eucaryotic organisms and appears
to play an important role in many cellular functions. This enzyme in yeast has a tetrameric structure composed of two catalytic
(α and/or α′) subunits and two regulatory β and β′ subunits. Previously, we have reported isolation from yeast cells four
active forms of CK2, composed of αα′ββ′, α2ββ′, α′2ββ′ and a free α′-catalytic subunit. Now, we report that in Saccharomyces cerevisiae CK2 holoenzyme regulatory β subunit cannot substitute other β′ subunit and only both of them can form fully active enzymatic
unit. We have examined the subunit composition of tetrameric complexes of yeast CK2 by transformation of yeast strains containing
single deletion of the β or β′ regulatory subunits with vectors carrying lacking CKB1 or CKB2 genes. CK2 holoenzyme activity was restored only in cases when both of them were present in the cell. Additional, co-immunoprecypitation
experiments show that polyadenylation factor Fip1 interacts with catalytic α subunits of CK2 and interaction with beta subunits
in the holoenzyme decreases CK2 activity towards this protein substrate. These data may help to elucidate the role of yeast
protein kinase CK2β/β′ subunits in the regulation of holoenzyme assembly and phosphotransferase activity. 相似文献
54.
Chemosensory proteins in the honey bee: Insights from the annotated genome, comparative analyses and expressional profiling 总被引:5,自引:0,他引:5
Small chemosensory proteins (CSPs) belong to a conserved, but poorly understood protein family that has been implicated in transporting chemical stimuli within insect sensilla. However, their expression patterns suggest that these molecules are also critical for other functions including early development. Here we used both bioinformatics and experimental approaches to characterize the CSP gene family in a social insect, the Western honey bee Apis mellifera, and then compared its members to CSPs in other arthropods. The number of CSPs in the honey bee genome (six) is similar to that found in the sequenced dipteran species (four-seven), but is much lower than the number of CSPs in the moth or in the beetle (around 20 each). These differences seem to be the result of lineage specific expansions. Our analysis of CSPs in a number of arthropods reveals a conserved gene family found in both Mandibulates and Chelicerates. Expressional profiling in diverse tissues and throughout development reveals broader than expected patterns of expression with none of the CSPs restricted to the antennae and one found only in the queen ovaries and in embryos. We conclude that CSPs are multifunctional context-dependent proteins involved in diverse cellular processes ranging from embryonic development to chemosensory signal transduction. Some CSPs may function in cuticle synthesis, consistent with their evolutionary origins in the arthropods. 相似文献
55.
56.
To determine the effect of prenatal lead exposure on brain monoaminergic systems, pregnant rats were given tap water containing
250 ppm lead acetate, for the duration of pregnancy, while tap water without lead (Pb2+) was substituted at birth. Control rats were derived from dams that consumed tap water during pregnancy, and had no exposure
to lead afterwards. At 12 weeks after birth, Pb2+ content of brain cortex was increased 3- to 4-fold (P < 0.05). At this time the endogenous striatal levels of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid were
19% lower in Pb2+ exposed rats (P < 0.05), while there was no change in the striatal level of dopamine (DA), noradrenaline, 3,4-dihydroxyphenylglycol, serotonin
(5-HT) and 5-hydroxyindoleacetic acid (HPLC/ED). Also there was no change in these monoamines and metabolites in the prefrontal
cortex of Pb2+ exposed rats. However, turnover of 5-HT in prefrontal cortex, as indicated by 5-hydroxytryptophan accumulation 30 min after
acute treatment with the decarboxylase inhibitor NSD-1015 (100 mg/kg IP), was lower in the Pb2+ exposed rats. In the striatum AMPH-induced (1 mg/kg IP) turnover of DA, evidenced as L-DOPA accumulation after NSD-1015,
was increased to a lesser extent in the Pb2+ exposed rats (P < 0.05). The nitric oxide synthase inhibitor 7-nitroindazole (10 mg/kg IP) attenuated the latter effect, indicating that
neuronal NO mediates this AMPH effect, at least in part. Moreover, DA D2 receptor sensitivity developed in Pb2+ exposed rats, as evidenced by enhanced quinpirole-induced yawning activity and enhanced quinpirole-induced locomotor activity
(each, P < 0.05). These findings indicate that ontogenetic exposure to lead can have consequences on monoaminergic neuronal function
at an adult stage of life, generally promoting accentuated behavioral effects of direct and indirect monoaminergic agonists,
and related to increased dopamine turnover in basal ganglia.
Special issue dedicated to Dr. Moussa Youdim. 相似文献
57.
Angel R Barchuk Alexandre S Cristino Robert Kucharski Luciano F Costa Zilá LP Simões Ryszard Maleszka 《BMC developmental biology》2007,7(1):70
Background
In honeybees, differential feeding of female larvae promotes the occurrence of two different phenotypes, a queen and a worker, from identical genotypes, through incremental alterations, which affect general growth, and character state alterations that result in the presence or absence of specific structures. Although previous studies revealed a link between incremental alterations and differential expression of physiometabolic genes, the molecular changes accompanying character state alterations remain unknown. 相似文献58.
Kowalska J Lewdorowicz M Zuberek J Bojarska E Stepinski J Stolarski R Darzynkiewicz E Jemielity J 《Nucleosides, nucleotides & nucleic acids》2007,26(10-12):1301-1305
Enzymatic cleavage of the P-chiral diastereoisomers of the 5' mRNA cap analogue bearing phosphorothioate moiety in alfa position of 5',5'-triphosphate bridge (m(7)Gppp(S)G D1 and D2) was performed by human Decapping Scavenger (DcpS) enzyme. Analysis of the degradation products allowed to estimate the absolute configuration at the asymmetric phosphorus atoms in examined compounds via correlation with the R(P) and S(P) diastereoisomers of guanosine 5'-O-(1-thiodiphosphate) (GDPalphaS). 相似文献
59.
Oligonucleotide microarrays are widely used in various biological studies. In this review, application of oligonucleotide microarrays for identifying binding sites and probing structure of RNAs is described. Deep sequencing allows fast determination of DNA and RNA sequence. High-throughput methods for determination of secondary structures of RNAs have also been developed. Those methods, however, do not reveal binding sites for oligonucleotides. In contrast, microarrays directly determine binding sites while also providing structural insights. Microarray mapping can be used over a wide range of experimental conditions, including temperature, pH, various cations at different concentrations and the presence of other molecules. Moreover, it is possible to make universal microarrays suitable for investigations of many different RNAs, and readout of results is rapid. Thus, microarrays are used to provide insight into oligonucleotide sequences potentially able to interfere with biological function. Better understanding of structure–function relationships of RNA can be facilitated by using microarrays to find RNA regions capable to bind oligonucleotides. That information is extremely important to design optimal sequences for antisense oligonucleotides and siRNA because both bind to single-stranded regions of target RNAs. 相似文献
60.
Wioleta?Kellmann-Sopy?aEmail author Les?aw?B.?Lahuta Irena?Gie?wanowska Ryszard?J.?Górecki 《Acta Physiologiae Plantarum》2015,37(6):118
The accumulation of soluble carbohydrates in maturing diaspores of flowering plants comprising Arctic populations of Cerastium alpinum, indigenous Antarctic species Colobanthus quitensis and Deschampsia antarctica, and cosmopolitan Poa annua from the Antarctic was investigated. For comparative purposes, the diaspores of two species of flowering plants growing in the area of Olsztyn (Poland), Poa annua (Poaceae) and Cerastium arvense (Caryophyllaceae) were used. A qualitative and quantitative analysis of soluble carbohydrates conducted by means of high-resolution gas chromatography showed that monosaccharides (glucose and fructose), maltose and sucrose, raffinose, myo-inositol and galactinol are ubiquitous in developing and mature diaspores among investigated species. Moreover, D. antarctica and P. annua caryopses additionally contained stachyose and 1-kestose; the seeds of Caryophyllaceae studied were found to contain d-pinitol and d-ononitol. The development and maturation of the seeds of polar Caryophyllaceae and Poaceae were accompanied by the changes in the concentration of their soluble carbohydrates. During maturation, seeds accumulated galactinol and raffinose family of oligosaccharides (RFOs), except C. quitensis. Although seeds of the studied Caryophyllaceae contained d-pinitol and lower amounts of d-ononitol, they did not accumulate α-d-galactoside derivatives of mentioned cyclitols. P. annua caryopses, occurring in the Antarctic, were found to accumulate considerably higher amounts of sucrose and 1-kestose than those developed in Olsztyn. 相似文献