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131.
目的探讨我国不同地域红色毛癣菌分离株的遗传多样性。方法采用随机扩增DNA多态性(RAPD)方法对来源于我国不同地域(江苏南京,山东济南,广东广州)的32株红色毛癣菌临床分离株进行DNA多态性分析。结果红色毛癣菌种内差异明显,根据遗传相似性分成三大聚类群,与地域差异及取材部位无明显相关性,而与表型具有一定相关性。结论随机扩增DNA多态性方法可用于红色毛癣菌的DNA分型,其DNA带型具有一定的遗传变异性,与菌株表型有一定关系,与地域差异、侵犯部位无明显相关性。 相似文献
132.
Anita?Kuras Ma?gorzata?Korbin Edward??urawiczEmail author 《Plant Cell, Tissue and Organ Culture》2004,79(2):189-193
Two PCR-based techniques, RAPD and ISSR, were utilized for determination of genetic relationship of 24 strawberry cultivars used in breeding program at the Research Institute of Pomology and Floriculture in Poland. Polymorphism of investigated genotypes was observed in reactions with 23 out of 48 tested RAPD primes and 41 from 90 tested ISSR primers. Relationship, determined on the base of polymorphic products analysis and showed in the form of dendrograms (UPGMA percent method), was generally similar for both techniques, although similarity values based on ISSR data were higher than those based on RAPD. The parallel use of two data sets seems to allow for precise estimation of cultivars relationship and diminishing mistakes connected with methods' technical limitations. 相似文献
133.
We characterized the population genetic structure of the Australian social spider Diaea ergandros using polymorphic allozyme markers. Our main objectives were to understand the social organization of D. ergandros and discern patterns of gene flow across distantly separated geographical areas. Spiders were sampled from nests located within 100 m wide locales, which were distributed within larger 50 km wide regions. Our results indicated that nestmates could have been produced by a single mother and father in 88.9% of D. ergandros nests. The remainder of nests contained spiders that were probably produced by polyandrous females or were immigrants from foreign nests. Nestmate relatedness was relatively high (r = 0.44) and did not differ significantly between the sexes or among juvenile, subadult and adult life stages. We also discovered that D. ergandros populations were highly structured, with significant differentiation detected among locales (FLR = 0.23) and regions (FRT = 0.081). Spiders within locales were also substantially inbred (FIL = 0.15). Overall, our data show that significant population subdivision exists in D. ergandros populations, and we suggest that the poor dispersal ability of Diaea spiders can account for the observed genetic structure. 相似文献
134.
Igaz P Pap E Patócs A Falus A Tulassay Z Rácz K 《The Journal of steroid biochemistry and molecular biology》2002,82(4-5):359-367
Alterations of steroid hormone biosynthesis and metabolism are suspected to be involved in the pathogenesis of several diseases. Several polymorphisms of the enzymes involved in these processes have already been described and some could be associated with certain diseases. We attempted to examine the sequence variants of these genes in order to find novel variants by an in silico analysis. We analyzed the known human nucleotide sequences of the enzymes p450 side-chain cleavage enzyme, steroid 17-alpha-hydroxylase/17,20-lyase, 3-beta-hydroxysteroid dehydrogenase types 1 and 2, 21-hydroxylase, 11-beta-hydroxylase, aldosterone synthase, aromatase, 11-beta-hydroxysteroid dehydrogenase types 1 and 2, steroid 5-alpha-reductase types 1 and 2, steroid 5-beta-reductase, dehydroepiandrosterone sulfotransferase, 17-beta-hydroxysteroid dehydrogenase types 1–3. The analysis was performed using the National Center for Biotechnology Information Database by the search tool blastn. We found numerous sequence variants in both coding and non-coding sequences. The majority of these sequence variants have already been described, nevertheless, some appear as novel variants. Some of these may also have functional significance. We hypothesize over the possible significance of these findings and briefly review the available literature. 相似文献
135.
Lehväslaiho H 《Briefings in bioinformatics》2000,1(2):161-166
This paper aims to give an overview of current resources onhuman sequence variations and give an idea about the directionin which these services are moving. 相似文献
136.
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138.
Aerides vandarum and Vanda stangeana are two rare and endangered vandaceous orchids with immense floricultural traits. The intergeneric hybrids were synthesized
by performing reciprocal crosses between them. In vitro germination response of the immature hybrid embryos was found to be
best on half-strength Murashige and Skoog medium supplemented with 20% (v/v) coconut water/liquid endosperm from tender coconut. Determination of hybridity was made as early as the immature seeds or
embryos germinated in vitro, using randomly amplified polymorphic DNA (RAPD) markers. Out of 15 arbitrarily chosen decamer
RAPD primers, two were found to be useful in amplification of polymorphic bands specific to the parental species and their
presence in the reciprocal crosses. However, a decisive profile that can identify the reciprocal crosses could not be provided
by RAPD. Amplification of the trnL-F non-coding regions of chloroplast DNA of the parent species and hybrids aided easy identification of the reciprocal crosses
from the fact that maternal inheritance of chloroplast DNA held true for these intergeneric hybrids. Subsequent restriction
digestion of the polymerase chain reaction (PCR) amplified trnL-F non-coding regions of chloroplast DNA also consolidated the finding. Such PCR-based molecular markers could be used for
early determination of hybridity and easy identification of the reciprocal crosses. 相似文献
139.
《Molecular cell》2021,81(24):5099-5111.e8
140.
Leigh A. Nelson Christine L. Lambkin Philip Batterham James F. Wallman Mark Dowton Michael F. Whiting David K. Yeates Stephen L. Cameron 《Gene》2012
Members of the Calliphoridae (blowflies) are significant for medical and veterinary management, due to the ability of some species to consume living flesh as larvae, and for forensic investigations due to the ability of others to develop in corpses. Due to the difficulty of accurately identifying larval blowflies to species there is a need for DNA-based diagnostics for this family, however the widely used DNA-barcoding marker, cox1, has been shown to fail for several groups within this family. Additionally, many phylogenetic relationships within the Calliphoridae are still unresolved, particularly deeper level relationships. Sequencing whole mt genomes has been demonstrated both as an effective method for identifying the most informative diagnostic markers and for resolving phylogenetic relationships. Twenty-seven complete, or nearly so, mt genomes were sequenced representing 13 species, seven genera and four calliphorid subfamilies and a member of the related family Tachinidae. PCR and sequencing primers developed for sequencing one calliphorid species could be reused to sequence related species within the same superfamily with success rates ranging from 61% to 100%, demonstrating the speed and efficiency with which an mt genome dataset can be assembled. Comparison of molecular divergences for each of the 13 protein-coding genes and 2 ribosomal RNA genes, at a range of taxonomic scales identified novel targets for developing as diagnostic markers which were 117–200% more variable than the markers which have been used previously in calliphorids. Phylogenetic analysis of whole mt genome sequences resulted in much stronger support for family and subfamily-level relationships. The Calliphoridae are polyphyletic, with the Polleninae more closely related to the Tachinidae, and the Sarcophagidae are the sister group of the remaining calliphorids. Within the Calliphoridae, there was strong support for the monophyly of the Chrysomyinae and Luciliinae and for the sister-grouping of Luciliinae with Calliphorinae. Relationships within Chrysomya were not well resolved. Whole mt genome data, supported the previously demonstrated paraphyly of Lucilia cuprina with respect to L. sericata and allowed us to conclude that it is due to hybrid introgression prior to the last common ancestor of modern sericata populations, rather than due to recent hybridisation, nuclear pseudogenes or incomplete lineage sorting. 相似文献