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SUMMARY: The biogenesis and differentiation (B&D) of amyloplasts contributes to fruit flavor and color. Here, remodeling of starch granules, thylakoids and plastoglobules was observed during development and ripening in two kiwifruit (Actinidia spp.) cultivars – yellow‐fleshed 'Hort16A' and green‐fleshed 'Hayward'. A protocol was developed to purify starch‐containing plastids with a high degree of intactness, and amyloplast B&D was studied using label‐free‐based quantitative proteomic analyses in both cultivars. Over 3000 amyloplast‐localized proteins were identified, of which >98% were quantified and defined as the kfALP (kiwifruit amyloplast proteome). The kfALP data were validated by Tandem‐Mass‐Tag (TMT) labeled proteomics in 'Hort16A'. Analysis of the proteomic data across development and ripening revealed: 1) a conserved increase in the abundance of proteins participating in starch synthesis/degradation during both amyloplast B&D; 2) up‐regulation of proteins for chlorophyll degradation and of plastoglobule‐localized proteins associated with chloroplast breakdown and plastoglobule formation during amyloplast differentiation; 3) constitutive expression of proteins involved in ATP supply and protein import during amyloplast B&D. Interestingly, two different pathways of amyloplast B&D were observed in the two cultivars. In 'Hayward', significant increases in abundance of photosynthetic‐ and tetrapyrrole metabolism‐related proteins were observed, but the opposite trend was observed in 'Hort16A'. In conclusion, analysis of the kfALP provides new insights into the potential mechanisms underlying amyloplast B&D with relevance to key fruit quality traits in contrasting kiwifruit cultivars. [ABSTRACT FROM AUTHOR]

SUMMARY: During fruit ripening, polygalacturonases (PGs) are key contributors to the softening process in many species. Apple is a crisp fruit that normally exhibits only minor changes to cell walls and limited fruit softening. Here, we explore the effects of PG overexpression during fruit development using transgenic apple lines overexpressing the ripening‐related endo‐POLYGALACTURONASE1 gene. MdPG1‐overexpressing (PGox) fruit displayed early maturation/ripening with black seeds, conversion of starch to sugars and ethylene production occurring by 80 days after pollination (DAP). PGox fruit exhibited a striking, white‐skinned phenotype that was evident from 60 DAP and most likely resulted from increased air spaces and separation of cells in the hypodermis due to degradation of the middle lamellae. Irregularities in the integrity of the epidermis and cuticle were also observed. By 120 DAP, PGox fruit cracked and showed lenticel‐associated russeting. Increased cuticular permeability was associated with microcracks in the cuticle around lenticels and was correlated with reduced cortical firmness at all time points and extensive post‐harvest water loss from the fruit, resulting in premature shrivelling. Transcriptomic analysis suggested that early maturation was associated with upregulation of genes involved in stress responses, and overexpression of MdPG1 also altered the expression of genes involved in cell wall metabolism (e.g. β‐galactosidase, MD15G1221000) and ethylene biosynthesis (e.g. ACC synthase, MD14G1111500). The results show that upregulation of PG not only has dramatic effects on the structure of the fruit outer cell layers, indirectly affecting water status and turgor, but also has unexpected consequences for fruit development. [ABSTRACT FROM AUTHOR]

SUMMARY: Chromoplasts act as a metabolic sink for carotenoids, in which plastoglobules serve as versatile lipoprotein particles. PGs in chloroplasts have been characterized. However, the features of PGs from non‐photosynthetic plastids are poorly understood. We found that the development of chromoplast plastoglobules (CPGs) in globular and crystalloid chromoplasts of citrus is associated with alterations in carotenoid storage. Using Nycodenz density gradient ultracentrifugation, an efficient protocol for isolating highly purified CPGs from sweet orange (Citrus sinensis) pulp was established. Forty‐four proteins were defined as likely comprise the core proteome of CPGs using comparative proteomics analysis. Lipidome analysis of different chromoplast microcompartments revealed that the nonpolar microenvironment within CPGs was modified by 35 triacylglycerides, two sitosterol esters, and one stigmasterol ester. Manipulation of the CPG‐localized gene CsELT1 (esterase/lipase/thioesterase) in citrus calli resulted in increased lipids and carotenoids, which is further evidence that the nonpolar microenvironment of CPGs contributes to carotenoid accumulation and storage in the chromoplasts. This multi‐feature analysis of CPGs sheds new light on the role of chromoplasts in carotenoid metabolism, paving the way for manipulating carotenoid content in citrus fruit and other crops. [ABSTRACT FROM AUTHOR]

Scholarship conducted in an increasingly online environment requires the services of a trusted third party in order to ensure that scholarly communication remains reliably accessible and applicable over the longer term. The library, by virtue of its most fundamental values and attributes, is probably better suited at this time than other information intermediaries to assume such a role. In order to understand the nature and responsibility of the trusted third party, or fair witness, it is essential to consider the key concept of transversality (especially as it is defined by the German philosopher Wolfgang Welsch) as it relates to information services. Assuming the role of trusted third party will also require that the academic library be prepared to undertake some fundamental changes in currently prevalent directions and values that will affect its relationship to other information intermediaries and, potentially, also to its parent institution.

Background: To address the limited provision of longer-term stroke care, we conducted a programme of research (LoTS2Care) to develop and test an intervention to form part of a replicable longer-term care strategy. New Start, a programme of facilitated self-management, was developed to be delivered at 6 months post-stroke by trained facilitators. Here, we report the findings from the final workstream of this programme, which aimed to evaluate the feasibility and acceptability of implementing a future definitive cluster randomised controlled trial of the developed intervention (New Start) to support stroke survivors and their carers in the longer term. Methods: A feasibility cluster randomised controlled trial was conducted in English and Welsh NHS stroke services. Stroke services (clusters) were randomised on a 1:1 basis to implement New Start or continue with usual care only. Community-dwelling stroke survivors between 4 and 6 months post-stroke were invited to participate in the trial by post. Outcome measures were collected via post at 3, 6 and 9 months after recruitment. Recruitment and follow-up rates, delivery and uptake of the intervention, data collection feasibility (including postal outcome measures of health and disability, mental well-being at 3, 6, and 9 months post-recruitment) and safety were assessed. Results: Ten stroke services were recruited. A total of 1127 stroke survivors were screened for participation, and 269 were registered (New Start, n = 145; usual care, n = 124). Retention was high with 239 (89%) stroke survivors being available for follow-up at 9 months, and high return rates of postal questionnaires were achieved (80.3% at 9 months). Intervention training was successfully delivered, and New Start was offered to 95.2% of trial participants in the intervention arm. Uptake was variable, however, ranging from 11.8 to 75.0%. There were no safety concerns. Conclusions: Stroke service recruitment and longer-term stroke survivor postal recruitment and outcome data collection are feasible; however, refinement of intervention targeting and delivery is required prior to undertaking a definitive trial. Trial registration: ISRCTN38920246. Registered 22 June 2016 (http://www.isrctn.com/ISRCTN38920246). [ABSTRACT FROM AUTHOR]

This article aims to suggest answers to two questions: What should be the primary purpose of information services in general and libraries in particular as we enter the new millennium? Assuming such a purpose, what array of services should the library be prepared to provide? These questions are approached mainly from the academic library perspective but are applicable to all library types. (AEF)