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21.
Usdin K; Chevret P; Catzeflis FM; Verona R; Furano AV 《Molecular biology and evolution》1995,12(1):73-82
The single most difficult problem in phylogenetic analysis is deciding
whether a shared taxonomic character is due to common ancestry or one that
appeared independently due to convergence, parallelism, or reversion to an
ancestral state. Mammalian L1 retrotransposons undergo periodic
amplifications in which multiple copies of the elements are interspersed in
the genome. Because these elements apparently are transmitted only by
inheritance and are retained in the genome, a shared L1 amplification event
can only be an inherited ancestral character. We propose that L1
amplification events can be an excellent tool for analyzing mammalian
evolution and demonstrate here how we addressed several refractory problems
in rodent systematics using L1 DNA as a taxonomic character.
相似文献
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Summary The paper deals with three new species of Deuteromycetous fungi e.g.Diplodia acaciae, Cytospora acaciae, andFusicoccum indicum collected on dead stems ofAcacia arabica
Linn. 相似文献
24.
G. Mustafa Saifi Preetha Tilak Reiner Veitia I. Manorama Thomas Avirachan Tharapel Ken Mcelreavey Mark Fellous H. Sharat Chandra 《Journal of genetics》1999,78(3):157-161
We describe a novel mutation in the coding region of theSRY gene in a 46, XY female with Swyer syndrome. Analysis ofSRY was carried out by direct sequencing of a 780-bp PCR product that included theSRY open reading frame (ORF). This revealed the presence of a point mutation, ins 108A, in the coding region 5’ to the HMG box which results in a frame shift and premature termination of the encoded protein. No other mutation was found in theSRY ORF. We infer that sex reversal in this individual is a result of this insertion. In none of the 13 other 46, XY females that were studied was a mutation detected inSRY, confirming earlier findings that most cases of XY femaleness are due to causes other than mutation inSRY. These observations and those of others are discussed in relation to the aetiology of XY sex reversal. 相似文献
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Rapid prototyping of distributed systems can be achieved by integrating commercial off-the-shelf (COTS) components. With components
as the building blocks, it is important to predict the performance of the system based on the performance of individual components.
In this paper, performance prediction of a system consisting of a small number of components is investigated under different
inter-component communication patterns, and the number of threads provided by components. Based on the experimental results,
it can be inferred that the proposed composition rules provide a reasonably accurate prediction of the performance of a system
made out of these components.
相似文献
Barrett R. BryantEmail: |
28.
Maganti S. Madhav Parikshit Plaha Nagendra K. Singh Tilak R. Sharma 《Journal of Phytopathology》2009,157(5):322-324
Identification of full length genes along with upstream regulatory elements is important to understand its expression. Here, we report preparation of high titre genomic library and identification of a genomic clone containing Pi-k h gene with its complete upstream and downstream sequences from the rice blast resistant line Tetep. Structural analysis of protein revealed that Pi-k h has a central nucleotide binding site domain, leucine-rich repeats domain and a unique zinc-finger domain. Comparative analysis of Pi-k h protein sequence showed 64% and 45% similarity with the protein sequences of rice blast resistance genes Pi-b and Pi-ta , respectively. 相似文献
29.
Rahul Kaldate Maneet Rana Vikas Sharma Hideki Hirakawa Rahul Kumar Gagandeep Singh Rakesh Kumar Chahota Sachiko N. Isobe Tilak Raj Sharma 《Molecular breeding : new strategies in plant improvement》2017,37(8):103
Horsegram [Macrotyloma uniflorum (Lam.) Verdc.] commonly known as kulthi or Madras gram is an important drought tolerant legume crop used as food and fodder in India and across the globe. Horsegram is tolerant to many biotic and abiotic stresses and considered a potential future food legume. Despite being a multiutility crop, insufficient genomic information is available in this species, which is otherwise required for genetic improvement. Hence, in the present work we used next-generation sequencing (NGS) technology for genome-wide development and characterization of novel simple sequence repeat (SSR) markers in horsegram. In all, 2458 SSR primer pairs were designed from NGS data and 117 SSRs were characterized in 48 diverse lines of horsegram. Cross-transferability of these markers was also checked in nine related legume species. The polymorphic SSRs revealed high diversity measures such as mean values of expected heterozygosity (He; 0.54), observed heterozygosity (Ho; 0.64), and polymorphism information content (PIC; 0.46). Analysis of molecular variance (AMOVA) revealed high degree of genetic variance within the populations. Dendrogram based on Jaccard’s similarity coefficient and principal component analysis (PCA) revealed two groups in the analyzed accessions. This observation was further confirmed by Bayesian genetic STRUCTURE analysis. The SSR markers developed herein can be used in diverse genetic analysis including association mapping in this crop and also in related legume crops with limited marker resources. Hence, this new SSR dataset can be useful for molecular breeding research in this underutilized pulse crop. In addition, genetic diversity estimates of analyzed germplasm can be important for devising future breeding programmes in horsegram. 相似文献
30.
Baicalein (5, 6, 7-trihydroxy-2-phenyl-4H-1-benzopyran-4-one), a naturally occurring flavone present in some of the medicinal plants is known for its potential therapeutic effects, such as cardioprotective, anticancer and anti-inflammatory properties. However, detailed role and mechanisms behind its protective properties against different generators for oxidative stress have not been examined. In the present study, we investigated the possible protective ability of baicalein against the membrane damage caused by reactive oxygen species (ROS) and reactive nitrogen species (RNS) and the mechanisms involved using pulse radiolysis technique. Baicalein offered efficient protection even at a concentration of 10 microM towards membrane damage caused by lipid peroxidation induced by the gamma-radiation, peroxyl radicals, ascorbate-Fe2+ and peroxynitrite in rat liver mitochondria and heart homogenate. To elucidate its reaction mechanisms with biologically relevant radicals, transient absorption spectroscopy employing pulse radiolysis technique was used. Baicalein showed fairly high rate constants (3.7 x 10(9), 1.3 x 10(9) and 8.0 x 10(8) dm3 mol(-1) s(-1) for hydroxyl, azidyl and alkylchloroperoxyl radicals, respectively), suggesting that baicalein can act as an effective scavenger of these radicals. In each case, the phenoxyl radical of baicalein was generated. Thus, it was evident that the phenolic moiety of baicalein was responsible for the free radical scavenging process. Baicalein also reacts with linoleic acid peroxyl radical (LOO*), indicating its ability to act as a chain breaking antioxidant. Peroxynitrite-mediated radicals were shown to be reactive towards baicalein and the bimolecular rate constants were 2.5 x 10(7) and 3 x 10(8) dm3 mol(-1) s(-1) for *NO2 and CO3*(-) radicals, respectively. In conclusion, our results revealed the potential of baicalein in protecting mitochondrial membrane against oxidative damage induced by the four different agents. We propose that the protective effect is mediated via scavenging of primary and secondary radicals generated during oxidative stress. 相似文献