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51.
Phylogenetic relationships of bolitoglossine salamanders: a demonstration of the effects of combining morphological and molecular data sets 总被引:2,自引:0,他引:2
We analyzed sequence data for 555 bp of the mitochondrial gene cytochrome b
in plethodontid salamanders, taken from 18 ingroup (tribe Bolitoglossini)
and 4 outgroup (tribe Plethodontini) taxa. There were 257 variable sites,
of which 219 were phylogenetically informative. Sequence differences among
taxa exceeded 20%, and there were up to 15% amino acid differences among
the sequences. We also analyzed 37 morphological (including karyological)
characters, taken from the literature. Data were analyzed separately and
then combined using parsimony and likelihood approaches. There is little
conflict between the morphological and DNA data, and that which occurs is
at nodes that are weakly supported by one or both of the data sets. Treated
separately, the morphological and DNA data provide strong support for some
nodes but not for others. The combined data act synergistically so that
good support is obtained for nearly all of the nodes in the tree. Recent
divergences are supported by silent transitions, and older divergences are
supported by a combination of morphological, karyological, DNA
transversion, and amino acid changes. Eliminating silent changes from the
DNA data improves the consistency index and improves some bootstrap and
decay index values for several deeper branches in the tree. However, the
combined data set with all characters included provides a better supported
tree overall. Maximum likelihood and parsimony with all of the data give
not only the same topology but also remarkably similar branch lengths.
Results of this analysis support the monopoly of the supergenera
Hydromantes and Batrachoseps, and of a sister group relationship of
Batrachoseps and the supergenus Bolitoglossa (represented in this study one
species of the genus Bolitoglossa).
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52.
Nasibullin TR Belonogova VA Tuktarova IA Nikolaeva IE Karamova IM Mustafina OE 《Genetika》2011,47(9):1262-1266
Chemokine CCL2, or monocytic chemoatractant protein 1 (CCL2/MCP-1) plays an important role in the development of cardiovascular diseases. In the present study, genotypes of four polymorphic markers (rs1860190, rs1024611, rs3917887, and rs991804) of the CCL2gene were identified in the population of Tatars (residents of the Republic of Bashkortostan). Analysis of associations of these markers with essential hypertension (EH) was carried out. It was demonstrated that haplotype CCL2*A*G*D*T was associated with the increased risk of EH (P = 0.01; OR = 1.53). 相似文献
53.
David TR Coulson Simon Brockbank Joseph G Quinn Suzanne Murphy Rivka Ravid G Brent Irvine Janet A Johnston 《BMC molecular biology》2008,9(1):1-11
Background
Transfection of cells with gene-specific, single-stranded oligonucleotides can induce the targeted exchange of one or two nucleotides in the targeted gene. To characterize the features of the DNA-repair mechanisms involved, we examined the maximal distance for the simultaneous exchange of two nucleotides by a single-stranded oligonucleotide. The chosen experimental system was the correction of a hprt-point mutation in a hamster cell line, the generation of an additional nucleotide exchange at a variable distance from the first exchange position and the investigation of the rate of simultaneous nucleotide exchanges.Results
The smaller the distance between the two exchange positions, the higher was the probability of a simultaneous exchange. The detected simultaneous nucleotide exchanges were found to cluster in a region of about fourteen nucleotides upstream and downstream from the first exchange position.Conclusion
We suggest that the mechanism involved in the repair of the targeted DNA strand utilizes only a short sequence of the single-stranded oligonucleotide, which may be physically incorporated into the DNA or be used as a matrix for a repair process. 相似文献54.
Zimmerman PA; Katholi CR; Wooten MC; Lang-Unnasch N; Unnasch TR 《Molecular biology and evolution》1994,11(3):384-392
Polymerase chain reaction (PCR) products were characterized for a repeated
sequence family (designated "O-150") of the human filarial parasite
Onchocerca volvulus. In phylogenetic inferences, the O-150 sequences
clustered into closely related groups, suggesting that concerted evolution
maintains sequence homology in this family. Using a novel mathematical
model based on a nested application of an analysis of variance, we
demonstrated that African rainforest and savannah strain parasite
populations are significantly different. In contrast, parasites collected
in the New World are indistinguishable from African savannah strains of O.
volvulus. This finding supports the hypothesis that onchocerciasis was
recently introduced into the New World, possibly as a result of the slave
trade.
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55.
O. E. Mustafina K. Z. Bakhtijarova A. M. Mikhailova I. A. Tuktarova A. N. Khusainova T. R. Nasibullin R. V. Magjanov 《Russian Journal of Genetics》2008,44(3):350-356
Multiple sclerosis (MS) is a multifactorial disease of the central nervous system. The apolipoprotein E (APOE) and interleukin 1 β (IL1B) genes are considered to be candidate genes of MS. The aim of the study was to examine the hypothesis of the importance of APOE and IL1B gene polymorphisms in MS development in ethnic Tatars. DNA samples isolated by phenol-chloroform extraction from peripheral blood of 383 ethnic Tatars (120 MS patients and 263 healthy donors) were studied. 112C/R and 158R/C APOE gene polymorphisms as well as ?511T/C IL1B gene polymorphism were analyzed by polymerase chain reaction (PCR) followed by PCR product digestion by endonuclease. Odds ratio (OR) values were used for evaluation of the relative risk of alleles and(or) genotype combinations. It has been shown that APOE*2/*3 genotype is associated with low risk of the disease development (OR = 0.20) in women. A combined effect of APOE and IL1B allelic variants has been discovered indicating the increased risk of the disease development in the carriers of APOE*4 and IL1B*T/*T alleles (OR = 4.76). 相似文献
56.
Mustafina O. E. Tuktarova I. A. Bikmeeva A. M. Nasibullin T. R. Khusnutdinova E. K. 《Russian Journal of Genetics》2001,37(4):448-452
Polymorphism at the apolipoprotein E gene (apoE) in populations of the Volga–Ural region was studied by means of polymerase chain reaction. In the region examined the population-specific patterns of the apoE alleles and genotypes frequency distribution were established. The results obtained were compared with the literature data on the apoE polymorphism in other world populations. Substantial heterogeneity of different ethnic populations in respect to the apoE genotypes distribution and frequency was revealed. 相似文献
57.
Titin is the third most abundant protein in sarcomeres and fulfills a number of mechanical and signaling functions. Specifically, titin is responsible for most of the passive forces in sarcomeres and the passive visco-elastic behaviour of myofibrils and muscles. It has been suggested, based on mechanical testing of isolated titin molecules, that titin is an essentially elastic spring if Ig domain un/refolding is prevented either by working at short titin lengths, prior to any unfolding of Ig domains, or at long sarcomere (and titin) lengths when Ig domain un/refolding is effectively prevented. However, these properties of titin, and by extension of muscles, have not been tested with titin in its natural structural environment within a sarcomere. The purpose of this study was to gain insight into the Ig domain un/refolding kinetics and test the idea that titin could behave essentially elastically at any sarcomere length by preventing Ig domain un/refolding during passive stretch-shortening cycles. Although not completely successful, we demonstrate here that titin’s visco-elastic properties appear to depend on the Ig domain un/refolding kinetics and that indeed, titin (and thus myofibrils) can become virtually elastic when Ig domain un/refolding is prevented. 相似文献
58.
59.
Erdman V. V. Nasibullin T. R. Tuktarova I. A. Somova R. Sh. Mustafina O. E. 《Russian Journal of Genetics》2019,55(6):728-737
Russian Journal of Genetics - The aim of this study was to investigate the associations between the polymorphic loci in the JAK/STAT signaling pathway and the aging processes and longevity in the... 相似文献
60.
Timasheva Yanina Badykov Marat Akhmadishina Leysan Nasibullin Timur Badykova Elena Pushkareva Alfiya Plechev Vladimir Sagitov Ildus Zagidullin Naufal 《Molecular biology reports》2021,48(6):5355-5362
Molecular Biology Reports - Sick sinus syndrome (SSS) encompasses a group of conduction disorders characterized by the inability of sinoatrial node to perform its pacemaker function. Our aim was to... 相似文献