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Wendy A. Douglass Robert H. Hyland Christopher D. Buckley Aymen Al-Shamkhani Jacqueline M. Shaw Sarah L. Scarth David L. Simmons S.K.Alex Law 《FEBS letters》1998,440(3):125
The cysteine-rich region (CRR) of the β2 integrin subunit was replaced by that of β1 to give the chimera β2NV1. β2NV1 can combine with αL to form a variant leukocyte-function-associated antigen (LFA)-1 on COS cell surface, suggesting that the specificity of the β2 interaction with αL does not lie in the CRR. Unlike those expressing wild-type LFA-1, COS cells expressing αLβ2NV1 are constitutively active in intercellular adhesion molecule (ICAM)-1 adhesion. These results suggest that activation of LFA-1 involves the release of an intramolecular constraint, which is maintained, in part, by the authentic β2 CRR. 相似文献
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Grape thaumatin-like proteins (TLPs) play roles in plant-pathogen interactions and can cause protein haze in white wine unless removed prior to bottling. Different isoforms of TLPs have different hazing potential and aggregation behavior. Here we present the elucidation of the molecular structures of three grape TLPs that display different hazing potential. The three TLPs have very similar structures despite belonging to two different classes (F2/4JRU is a thaumatin-like protein while I/4L5H and H2/4MBT are VVTL1), and having different unfolding temperatures (56 vs. 62°C), with protein F2/4JRU being heat unstable and forming haze, while I/4L5H does not. These differences in properties are attributable to the conformation of a single loop and the amino acid composition of its flanking regions. 相似文献
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Lincoln D Stein 《Genome biology》2010,11(5):207
With DNA sequencing now getting cheaper more quickly than data storage or computation, the time may have come for genome informatics
to migrate to the cloud. 相似文献
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Rice fields are an alternative habitat for waterbirds and provide food and shelter for many avian species, but there is a lack of information about how the use of rice fields translates into population level effects. The aim of this study was to test the relationship between the use of rice fields by European waterbirds and trends in their populations. We tested this relationship during the autumn migration season and during the breeding season. Based on counts conducted over the last 23 years in natural marshes and areas of rice fields in Doñana (SW Spain), an index of rice field use was constructed for 76 bird species, which was then compared to these species’ European population trends obtained from the literature. A positive relationship was found between waterbird population trends and the use of rice fields during autumn migration season. Our study suggests that changes in the Common Agriculture Policy in Europe leading to reductions in areas of rice cultivation may have important effects on waterbirds. The restoration of former marsh areas and the maintenance of rice cultivation would seem to be more environmentally friendly approaches than the use of these areas to grow alternative crops or solar farms. 相似文献
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Robert S. Steneck 《Current biology : CB》2009,19(3):R117-R119
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