排序方式: 共有25条查询结果,搜索用时 0 毫秒
21.
A likelihood method for the detection of selection and recombination using nucleotide sequences 总被引:28,自引:12,他引:16
Different regions along nucleotide sequences are often subject to different
evolutionary forces. Recombination will result in regions having different
evolutionary histories, while selection can cause regions to evolve at
different rates. This paper presents a statistical method based on
likelihood for detecting such processes by identifying the regions which do
not fit with a single phylogenetic topology and nucleotide substitution
process along the entire sequence. Subsequent reanalysis of these anomalous
regions may then be possible. The method is tested using simulations, and
its application is demonstrated using the primate psi eta-globin
pseudogene, the V3 region of the envelope gene of HIV-1, and argF sequences
from Neisseria bacteria. Reanalysis of anomalous regions is shown to reveal
possible immune selection in HIV-1 and recombination in Neisseria. A
computer program which implements the method is available.
相似文献
22.
INTRODUCTIONRecombinant DNA technology is a powerful toolfor the introduction of foreign genes into longlivedperennials and fOr fundamelltal studies of gene expression. Using such techniques, we can overcomethe difficulties associated with the breeding of a long-lived perennial. At present, although considerablereseaxch effort has been devoted to the genetic en-gineering of fOrest trees, it has lagged behind ad-vances made in herbaceous crops due both to eco-nomics and the recalcitrant n… 相似文献
23.
Induced pluripotent stem(iPS) cells can be derived from human somatic cells by cellular reprogramming.This technology provides a potential source of non-controversial therapeutic cells for tissue repair,drug discovery,and opportunities for studying the molecular basis of human disease.Normally,mouse embryonic fibroblasts(MEFs) are used as feeder layers in the initial derivation of iPS lines.The purpose of this study was to determine whether SNL fibroblasts can be used to support the growth of human iPS cell... 相似文献
24.
25.
In their attempts to evade the host immune response, mammalian viruses have evolved a wide range of strategies. These include the expression and modification of various host cytokines and receptors. Understanding the mechanism of action of these virally encoded proteins will clearly deepen our insights into immunology. In the past few months several new virally encoded chemokines have been described which can modify both the host immune and antiviral response. Their manipulation of the cytokine structure-function relationship may also be useful in the development of reagents for treating immune and proliferative diseases. 相似文献