4 research outputs found
Fungi hijack a ubiquitous plant apoplastic endoglucanase to release a ROS scavenging beta-glucan decasaccharide to subvert immune responses
Plant pathogenic and beneficial fungi have evolved several strategies to evade immunity and cope with host-derived hydrolytic enzymes and oxidative stress in the apoplast, the extracellular space of plant tissues. Fungal hyphae are surrounded by an inner insoluble cell wall layer and an outer soluble extracellular polysaccharide (EPS) matrix. Here, we show by proteomics and glycomics that these two layers have distinct protein and carbohydrate signatures, and hence likely have different biological functions. The barley (Hordeum vulgare) β-1,3-endoglucanase HvBGLUII, which belongs to the widely distributed apoplastic glycoside hydrolase 17 family (GH17), releases a conserved β-1,3;1,6-glucan decasaccharide (β-GD) from the EPS matrices of fungi with different lifestyles and taxonomic positions. This low molecular weight β-GD does not activate plant immunity, is resilient to further enzymatic hydrolysis by β-1,3-endoglucanases due to the presence of three β-1,6-linked glucose branches and can scavenge reactive oxygen species. Exogenous application of β-GD leads to enhanced fungal colonization in barley, confirming its role in the fungal counter-defensive strategy to subvert host immunity. Our data highlight the hitherto undescribed capacity of this often-overlooked EPS matrix from plant-associated fungi to act as an outer protective barrier important for fungal accommodation within the hostile environment at the apoplastic plantâmicrobe interface
In planta expression of human polyQ-expanded huntingtin fragment reveals mechanisms to prevent disease-related protein aggregation
In humans, aggregation of polyglutamine repeat (polyQ) proteins causes disorders such as Huntingtonâs disease. Although plants express hundreds of polyQ-containing proteins, no pathologies arising from polyQ aggregation have been reported. To investigate this phenomenon, we expressed an aggregation-prone fragment of human huntingtin (HTT) with an expanded polyQ stretch (Q69) in Arabidopsis thaliana plants. In contrast to animal models, we find that Arabidopsis sp. suppresses Q69 aggregation through chloroplast proteostasis. Inhibition of chloroplast proteostasis diminishes the capacity of plants to prevent cytosolic Q69 aggregation. Moreover, endogenous polyQ-containing proteins also aggregate on chloroplast dysfunction. We find tha
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Ethnic Speech and Ethnic Action as Ethnic Behavior I: Construction of the Brunel Ethnic Behavior Inventory (BEBI)
In this article we report the construction of a new survey â specifically, the Brunel Ethnic Behavior Inventory (BEBI) â designed to measure ethnic speech and ethnic action as separate, yet related, aspects of individualsâ ethnic behavior. Using Tajfelâs (1981; Tajfel & Turner, 1986) social identity theory as our conceptual frame of reference, we sought an answer to the research question of how many factors actually are measured by the BEBI; and we tested the hypothesis that a two-factor model (i.e., ethnic speech and ethnic action as two correlated factors) would provide significantly better goodness-of-fit to the correlational data than would a one-factor model (i.e., ethnic behavior as one undifferentiated factor). Across one pilot sample (n = 101) and two main samples (n = 120 for Sample 1, n = 148 for Sample 2), we found that, not only did the BEBI measure two factors at most (i.e., ethnic speech and ethnic action); but consistent with our hypothesis, the two-factor model yielded better goodness-of-fit than did the one-factor model. Implications for the conceptualization and measurement of âways of ethnicityâ (Verkuyten, 2005) are discussed
The role of BACP in maximising the potential of counselling and psychological therapies research in the UK: benefitting clients, communities, and societies
The British Association for Counselling and Psychotherapy (BACP) is the largest professional membership body within the field of counselling and psychological therapies in the UK, but there is a mismatch between its membership of >65,000 and its research impact. This article sets out a potential strategic direction as considered by an informal grouping of researchers and teachers in the field. Actionable research plans are outlined at three levels: clientâpractitioner, local communities, and societies. At the clientâpractitioner level, dataâinformed practice can be readily implemented as a therapeutic aid akin to supervision, providing the potential for integrating research into everyday practice. At the community level, interdisciplinary collaborations together with a focus on equality, diversity, and inclusiveness are paths to building a community of researchers and citizens that includes marginalised populations. The importance of social justice extends to the societal level, connecting with politics at a micro and macro level, and engaging internationally to respond to actual threats (e.g., climate change). Across these three levels, high value is placed on data with its potential for informing and improving practice, but also enhancing the lives of people in communities and societies. Overall, research strategies need to be collaborative (i.e., collegial) and less singular (i.e., individually projectâbased), developing cumulative knowledge around specific topics via a âcapture and buildâ strategy for small projects with strategic oversight by BACP. Clarity of research strategy combined with collaborative and collective action from BACP and leaders in the field can help realise the full potential of BACP's research capacity