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Not AvailableFloodplain wetlands are among the most threatened ecosystems. It is highly vulnerable to climate change, affecting the wetland ecosystem and its associated fisheries. In the face of data deficiency, this article presents an alternative approach to assess the vulnerability of wetland fisheries to climate change. A total of 15 wetlands from a wetland-fisheries-rich area of West Bengal, India, were selected to illustrate the methodology. The proposed method mainly relies on stakeholders’ perceptions of the wetland fisheries vulnerability. Elicitation stakeholders’ response iteratively screened the indicators of fisheries vulnerability. The hybrid method of index-based vulnerability comprises two types of indicators: climate indicators with long-term quantitative data and stakeholder perceived vulnerability indicators specific to wetland fisheries. The high level of consensus (92%) among respondents provided strong evidence of climate change in last 15 years, which has also been validated through long-term data analysis. The Principal Component Analysis extracted five synthesized vulnerability indicators, explaining 83.35% variability of the original 14 indicators. The wetlands were further grouped according to differential vulnerability for prioritizing the wetlands for strategic planning. Climate change, reduction in species richness and adaptive capacity were the key components responsible for differential vulnerability. The study also revealed some indigenous climate-smart mitigation strategies of wetland fisheries to climate change.Not Availabl

Endoplasmic reticulum stress or mutation of an EF-hand Ca2+-binding domain directs the FKBP65 rotamase to an ERAD-based proteolysis

FKBP65 is an endoplasmic reticulum (ER)-localized chaperone and rotamase, with cargo proteins that include tropoelastin and collagen. In humans, mutations in FKBP65 have recently been shown to cause a form of osteogenesis imperfecta (OI), a brittle bone disease resulting from deficient secretion of mature type I collagen. In this work, we describe the rapid proteolysis of FKBP65 in response to ER stress signals that activate the release of ER Ca2+ stores. A large-scale screen for stress-induced cellular changes revealed FKBP65 proteins to decrease within 6–12 h of stress activation. Inhibiting IP3R-mediated ER Ca2+ release blocked this response. No other ER-localized chaperone and folding mediators assessed in the study displayed this phenomenon, indicating that this rapid proteolysis of folding mediator is distinctive. Imaging and cellular fractionation confirmed the localization of FKBP65 (72 kDa glycoprotein) to the ER of untreated cells, a rapid decrease in protein levels following ER stress, and the corresponding appearance of a 30-kDa fragment in the cytosol. Inhibition of the proteasome during ER stress revealed an accumulation of FKBP65 in the cytosol, consistent with retrotranslocation and a proteasome-based proteolysis. To assess the role of Ca2+-binding EF-hand domains in FKBP65 stability, a recombinant FKBP65-GFP construct was engineered to ablate Ca2+ binding at each of two EF-hand domains. Cells transfected with the wild-type construct displayed ER localization of the FKBP65-GFP protein and a proteasome-dependent proteolysis in response to ER stress. Recombinant FKBP65-GFP carrying a defect in the EF1 Ca2+-binding domain displayed diminished protein in the ER when compared to wild-type FKBP65-GFP. Proteasome inhibition restored mutant protein to levels similar to that of the wild-type FKBP65-GFP. A similar mutation in EF2 did not confer FKBP65 proteolysis. This work supports a model in which stress-induced changes in ER Ca2+ stores induce the rapid proteolysis of FKBP65, a chaperone and folding mediator of collagen and tropoelastin. The destruction of this protein may identify a cellular strategy for replacement of protein folding machinery following ER stress. The implications for stress-induced changes in the handling of aggregate-prone proteins in the ER–Golgi secretory pathway are discussed. This work was supported by grants from the National Institutes of Health (R15GM065139) and the National Science Foundation (DBI-0452587)