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To identify the role of caveolin-1 in integrin mechanotransduction, we exposed bovine aortic endothelial cells to 10 dyn/ [cm.sup.2] of laminar shear stress. Caveolin-1 was acutely and transiently phosphorylated with shear, occurring downstream of [[beta].sub.1]-integrin activation as the [[beta].sub.1]-integrin blocking antibody JB1A was inhibitory. In manipulating Src family kinase (SFK) activity with knockdown of Csk or type 1 protein phosphatase (PP1) treatment, we observed coordinate increase and decrease in shear-induced caveolin-1 phosphorylation, respectively. Hence, shear-stimulated caveolin-1 phosphorylation is regulated by SFKs. Shear-induced recruitment and phosphorylation of caveolin-1 occurred at [[beta].sub.1]-integrin sites in a [[beta].sub.1]-integrin- and SFK-dependent manner. Csk, described to interact with pY14-caveolin-1 and integrins, bound to an increased pool of phosphorylated caveolin-1 after shear corresponding with elevated Csk at [[beta].sub.1]-integrin sites. Like caveolin-1, treatment with JB1A and PP1 attenuated shear-induced Csk association with [[beta].sub.1]-integrins. Csk function was assayed with transfection of a caveolin-1 phosphorylation domain peptide. The peptide attenuated shear-induced association of Csk at [[beta].sub.1]-integrin sites, as well as colocalization of Csk with paxillin and phosphorylated caveolin-1. Because integrin and Csk activity regulate cytoskeletal reorganization, we evaluated the role of this mechanism in shear-induced myosin light chain (MLC) phosphorylation. Knockdown of Csk expression was sufficient to reduce MLC diphosphorylation due to shear. Disruption of Csk-integrin association by peptide treatment was also inhibitory of the MLC diphosphorylation response. Together these data indicate that integrin activation with shear stress results in SFK-regulated caveolin-1 phosphorylation that, in turn, mediates Csk association at integrin sites, where it plays a role in downstream, shear-stimulated MLC diphosphorylation. myosin light chain; caveolae; shear stress

Land system science axiomatically addresses social–environmental systems by integrating the dynamics of land uses (social) and land covers (environment), invariably including the use of remote sensing data and often, spatially explicit models of land change. This kind of research is illustrated through the Southern Yucatán Peninsular Region project (1997–2008) aimed at understanding, predicting, and projecting spatially explicit land change in a region with juxtaposed land uses-agriculture and a biosphere reserve. The successes of the project, its contributions to contemporary land system science, and the organizational mechanisms that fostered the research are identified as well as various corrections, which if applied, may have refined and extended the project's goals. Overall, the project demonstrates the kind of integrated research required to advance understanding of a social-environment system and the team-based methods used in the process. [ABSTRACT FROM AUTHOR]

The simplification of agricultural landscapes, particularly in the United States (US), has contributed to alarming rates of environmental degradation. As such, increasing agrobiodiversity throughout the US agri-food system is a crucial goal toward mitigating these harmful impacts, and crop diversification is one short-term mechanism to begin this process. However, despite mounting evidence of its benefits, crop diversification strategies have yet to be widely adopted in the US. Thus, we explore barriers and bridges to crop diversification for current farmers, focused on the Magic Valley of southern Idaho-a region with higher crop diversity relative to the US norm. We address two main research questions: (1) how and why do farmers in this region enact temporal and/or spatial strategies to manage crop diversity (the present) and (2) what are the barriers and bridges to alternative diversification strategies (the imaginary)? Through a political agroecology and spatial imaginaries lens, we conducted and analyzed 15 farmer and 14 key informant interviews between 2019 and 2021 to gauge what farmers are doing to manage crop diversity (the present) and how they imagine alternative landscapes (the imaginary). We show that farmers in this region have established a regionally diversified landscape by relying primarily on temporal diversification strategies-crop rotations and cover cropping-but do not necessarily pair these with other spatial diversification strategies that align with an agroecological approach. Furthermore, experimenting with and imagining new landscapes is possible (and we found evidence of such), but daily challenges and structural constraints make these processes not only difficult but unlikely and even "dangerous" to dream of. Therein, we demonstrate the importance of centering who is farming and why they make certain decisions as much as how they farm to support agroecological transformation and reckoning with past and present land use paradigms to re-imagine what is possible., Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-022-00833-0., Competing Interests: Conflict of interestThe authors declare no competing interests, (© INRAE and Springer-Verlag France SAS, part of Springer Nature 2022, Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

This paper scrutinizes the assertion that knowledge gaps concerning health risks from climate change are unjust, and must be addressed, because they hinder evidence-led interventions to protect vulnerable populations. First, we construct a taxonomy of six inter-related forms of invisibility (social marginalization, forced invisibility by migrants, spatial marginalization, neglected diseases, mental health, uneven climatic monitoring and forecasting) which underlie systematic biases in current understanding of these risks in Latin America, and advocate an approach to climate-health research that draws on intersectionality theory to address these inter-relations. We propose that these invisibilities should be understood as outcomes of structural imbalances in power and resources rather than as haphazard blindspots in scientific and state knowledge. Our thesis, drawing on theories of governmentality, is that context-dependent tensions condition whether or not benefits of making vulnerable populations legible to the state outweigh costs. To be seen is to be politically counted and eligible for rights, yet evidence demonstrates the perils of visibility to disempowered people. For example, flood-relief efforts in remote Amazonia expose marginalized urban river-dwellers to the traumatic prospect of forced relocation and social and economic upheaval. Finally, drawing on research on citizenship in post-colonial settings, we conceptualize climate change as an 'open moment' of political rupture, and propose strategies of social accountability, empowerment and trans-disciplinary research which encourage the marginalized to reach out for greater power. These achievements could reduce drawbacks of state legibility and facilitate socially-just governmental action on climate change adaptation that promotes health for all., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: To determine whether the β1 integrin/caveolin-1 signaling complex plays a role in shear stress regulation of RhoA activity ., Methods and Results: Hemodynamic shear stress influences the phenotype of the endothelium. Integrins and RhoA are essential components in the process that allows endothelial cells to adapt to flow. However, the signaling mechanisms that relay from integrins to RhoA are not well defined. Bovine aortic endothelial cells were subjected to laminar shear stress (10 dyne/cm(2)) for up to 6 hours. β1 integrin blockade inhibited Src family kinases and p190RhoGAP tyrosine phosphorylation observed after the immediate onset of shear stress. Depletion of caveolin-1 blocked the decline in p190RhoGAP tyrosine phosphorylation observed at later points by sustaining Src family kinase activity. The manipulation of β1 integrin and caveolin-1 also altered shear regulation of RhoA activity. More importantly, cells depleted of p190RhoGAP showed faulty temporal regulation of RhoA activity. Each of these treatments attenuated actin reorganization induced by flow. Similarly, stress fibers failed to form in endothelial cells exposed to enhanced blood flow in caveolin-1 knockout mice., Conclusions: Our studies demonstrate that p190RhoGAP links integrins and caveolin-1/caveolae to RhoA in a mechanotransduction cascade that participates in endothelial adaptation to flow.

We previously reported that caveolin-1 is a key component in a beta1 integrin-dependent mechanotransduction pathway suggesting that caveolae organelles and integrins are functionally linked in their mechanotransduction properties. Here, we exposed BAEC monolayers to shear stress then isolated caveolae vesicles form the plasma membrane. While little beta1 integrin was detected in caveolae derived from cells kept in static culture, shear stress induced beta1 integrin transposition to the caveolae. To evaluate the significance of shear-induced beta1 integrin localization to caveolae, cells were pretreated with cholesterol sequestering compounds or caveolin-1 siRNA to disrupt caveolae structural domains. Cholesterol depletion attenuated integrin-dependent caveolin-1 phosphorylation, Src activation and Csk association with beta1 integrin. Reduction of both caveolin-1 protein and membrane cholesterol inhibited downstream shear-induced, integrin-dependent phosphorylation of myosin light chain. Taken together with our previous findings, the data supports the concept that beta1 integrin-mediated mechanotransduction is mediated by caveolae domains.