An alternative to current thinking about positive selection, negative selection and activation of T cells
نویسندگان
چکیده
منابع مشابه
Thymic T-Cell Education: Positive & Negative Selection
TOLERANCE (which is antigen-specific) must be distinguished from immune deficiency (non-specific). Its most important manifestation, the maintenance of SELFTOLERANCE, was originally explained by the Clonal Selection theory as the result of CLONAL ABORTION of self-reactive clones. However, potentially self-reactive Tand B-cells do exist in normal individuals, leading to the recognition of the im...
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H ow has language developed in humans and what genetic changes underlie our unique cognitive abilities? Accounts of positive selection that lead to such abilities in humans fascinate us because of the insight they provide into our own evolution, and into the many genetic differences that distinguish us from other apes. The genes that became fi xed in our lineage as a result of positive selectio...
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This paper explores whether natural selection, a putative evolutionary mechanism, and a main one at that, can be characterized on either of the two dominant conceptions of mechanism, due to Glennan and the team of Machamer, Darden, and Craver, that constitute the new mechanistic philosophy'. The results of the analysis are that neither of the dominant conceptions of mechanism adequately capture...
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Alternative splicing is an important mechanism of generating protein diversity and accelerated genome evolution. The mode of the selection acting in constitutive, major alternative and minor alternative regions of human genes is different. Whereas constitutive and major alternative regions tend to evolve under negative (stabilizing) selection, alternatively spliced exons from minor isoforms exp...
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Detecting positive selection is a challenging task. We propose a method for detecting past positive selection through ongoing negative selection, based on comparison of the parameters of intraspecies polymorphism at functionally important and selectively neutral sites where a nucleotide substitution of the same kind occurred recently. Reduced occurrence of recently replaced ancestral alleles at...
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ژورنال
عنوان ژورنال: Immunology
سال: 2004
ISSN: 0019-2805,1365-2567
DOI: 10.1111/j.0019-2805.2004.01830.x