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Experimental and Applied Acarology - Assessing the risk of tick-borne disease in areas with high visitor numbers is important from a public health perspective. Evidence suggests that tick presence,...  相似文献   
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Human Ecology - I address a contentious element in forest property relations to illustrate the role of ownership in protecting and expanding of forest cover by examining the extent to...  相似文献   
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Background and AimsRoot sprouting (RS), i.e. the ability to form adventitious buds on roots, is an important form of clonal growth in a number of species, and serves as both a survival strategy and a means of spatial expansion, particularly in plants growing in severely and recurrently disturbed habitats. Occurrence and/or success of plants in severely and recurrently disturbed habitats are determined by two components, namely the ability to produce adventitious buds on roots and the vigour of their production. As mechanisms behind different magnitudes of RS remain unclear, our study investigates: (1) whether the presence or absence of specific tissues in roots can promote or limit RS; and (2) whether there is some relationship between RS ability, RS vigour and species niche.MethodsWe studied RS ability together with RS vigour in 182 Central European herbaceous species under controlled experimental conditions. We used phylogenetic logistic regressions to model the presence of RS, RS vigour, the relationship between RS and anatomical traits and the relationship between RS and parameters of species niches.Key ResultsA quarter of herbs examined were able to produce adventitious buds on roots. They were characterized by their preference for open dry habitats, the presence of secondary root thickening and the occurrence of sclerified cortical cells in roots. Root sprouting vigour was not associated with any specific anatomical pattern, but was correlated with the environmental niches of different species, indicating that preferred disturbed and dry habitats might represent a selection pressure for more vigorous root sprouters than undisturbed and wet habitats.ConclusionsOur study shows that sprouting from roots is quite common in temperate dicotyledonous herbs. Two components of RS – ability and vigour – should be considered separately in future studies. We would also like to focus more attention on RS in herbs from other regions as well as on external forces and internal mechanisms regulating evolution and the functions of RS in both disturbed and undisturbed habitats.  相似文献   
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The ubiquitin pathway regulates diverse functions including protein localization and stability. The complexity of the pathway involving nearly 40 identified E2 conjugating enzymes and over 600 E3 ligases raises the issue of specificity. With the E2s and E3s fitting into a limited number of classes based on bioinformatics, structures, and proven activities, there is not a clear picture as to what would determine which E2/E3 enzyme pair would be functional. There have been many reports of limited E2/E3 activity profiling with a small number of E2s and E3s. We have expanded on this to investigate the activity of ubiquitin E2s covering the majority of the reported classes/families in concert with a number of E3s implicated in a variety of diseases. Using an ELISA-based assay we screened 10 E3 ligases against a panel of 11 E2s to determine which E2/E3 pairs exhibited E3 autoubiquitylation activity. In addition, the ubiquitin chain linkage preference by certain E2/E3 pairs was investigated. Finally, substrate ubiquitylation was assayed for the E3 ligase MuRF1 using various E2/MuRF1 pairs. These studies demonstrate the utility of identifying the correct E2/E3 pair to monitor specific substrate ubiquitylation.  相似文献   
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The discovery of the Suppressor of Cytokine Signaling (SOCS) family of proteins has resulted in a significant body of research dedicated to dissecting their biological functions and the molecular mechanisms by which they achieve potent and specific inhibition of cytokine and growth factor signaling. The Australian contribution to this field has been substantial, with the initial discovery of SOCS1 by Hilton, Starr and colleagues (discovered concurrently by two other groups) and the following work, providing a new perspective on the regulation of JAK/STAT signaling. In this review, we reflect on the critical discoveries that have lead to our current understanding of how SOCS proteins function and discuss what we see as important questions for future research.  相似文献   
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