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Prefoldin is a molecular chaperone that captures an unfolded protein substrate and transfers it to a group II chaperonin. Previous studies have shown that the interaction sites for prefoldin are located in the helical protrusions of group II chaperonins. However, it does not exclude the possibility of the existence of other interaction sites. In this study, we constructed C-terminal truncation mutants of a group II chaperonin and examined the effects of these mutations on the chaperone's function and interaction with prefoldin. Whereas the mutants with up to 6 aa truncation from the C-terminus retained more than 90% chaperone activities for protecting citrate synthase from thermal aggregation and refolding of green fluorescent protein and isopropylmalate dehydrogenase, the truncation mutants showed decreased affinities for prefoldin. Consequently, the truncation mutants showed reduced transfer efficiency of the denatured substrate protein from prefoldin and subsequent chaperonin-dependent refolding. The results clearly show that the C-terminal region of group II chaperonins contributes to their interactions with prefoldin, the transfer of the substrate protein from prefoldin and its refolding., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Study Objectives: The first aim of this study was to investigate the effects of nutritional supplementation combined with low-intensity exercise on body components, exercise tolerance, and health-related quality of life (HRQOL) in malnourished patients with COPD. The second aim of this study was to examine the degree of systemic inflammation and the actual changes in levels of systemic CRP, TNFα, IL-6 and IL-8 actual changes after a combination of nutritional supplementation and low-intensity exercise in these patients., Design: A prospective randomized trial., Patients: Thirty-two moderate to severe, clinically stable malnourished COPD patients., Methods: Patients were randomly divided into a nutritional supplementation with low-intensity exercise group and a control group. Lung function, maximum inspiratory and expiratory muscle force, the Chronic Respiratory Disease Questionnaire (CRQ), the 6-min walking distance (6MWD), and the Borg scale were measured at baseline and were re-assessed at 3 months after intervention. The degree of systemic inflammation and the changes in levels of systemic CRP, TNFα, IL-6 and IL-8 were assessed before and after a combination nutritional supplementation with low-intensity exercise., Results: Body weight and FFM increased significantly after 12 weeks of nutritional supplementation therapy in patients with COPD. The dietary intake energy increased and the REE:REEpred ratio decreased significantly in the nutrition with low-intensity exercise group. PI(max), Quadriceps muscle force and the 6-min walking distance (6MWD) increased significantly from baseline through week 12. Health status, as assessed by CRQ, improved in the domains of dyspnea and total sores significantly in the nutrition with low-intensity exercise group after intervention. In this group, hsCRP, IL-6, IL-8, and TNFα, decreased significantly after intervention compared with the control group., Conclusions: The combination of nutritional supplementation with low-intensity exercise training was successful in increasing weight and energy intake as well as exercise capacity and health-related QOL in our patients. Moreover, REE and major inflammatory cytokines decreased significantly after nutritional supplementation with low-intensity exercise training. The present study results suggest a potential role for the combination of nutritional supplementation and low-intensity exercise in the management of malnourished patients with COPD., (Copyright © 2010 Elsevier Ltd. All rights reserved.)