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PURPOSE: The purpose of the article is to indicate the condition of local organizations whose role is to achieve socio-economic goals in regional areas in Poland. This is because the conditions in which such organizations operate have a significant impact on their achievement of their goals, which include social integration, building social capital, and helping disadvantaged groups., DESIGN/METHODOLOGY/APPROACH: The basic research tool used in the article is a quantitative, survey, Computer Assisted Web Interview covering the entire area of Poland by province. A representative sample of 300 entities was adopted. The survey had a nationwide character, so a proportional division of the research sample according to the number of Rural Housewives' Circles operating in each province of Poland was adopted., FINDINGS: Circles of Rural Housewives counted as Social Economy organizations carry out many important activities in the aspect of activation and social exclusion in the Polish territories. Their growing role and dynamic development can be seen. This activity is accompanied by barriers and problems with which KGW members must cope. Undoubted challenges are issues of financing, promotion of these organizations. We should also mention insufficient cooperation with the local government environment, lack of premises or complicated reporting procedure., PRACTICAL IMPLICATIONS: The results of the research, its conclusions and recommendations can become valuable material, indicating the problems and ways to solve them, helping to develop the social economy in Poland, in relation to Circles of Rural Housewives and small local communities, where the social economy is developing most dynamically., ORIGINALITY/VALUE: The article describes and verifies the assumptions of realization of social goals in the area of social economy, which especially in Poland has not been sufficiently described. There are also few primary and secondary materials describing the activities of organizations such as Rural Housewives' Circles in the literature., peer-reviewed

SummaryPlastid ribosomes are very similar in structure and function to ribosomes of their bacterial ancestors. Since ribosome biogenesis is not thermodynamically favourable at biological conditions, it requires activity of many assembly factors. Here, we have characterized a homolog of bacterialrsgAinArabidopsis thalianaand show that it can complement the bacterial homolog. Functional characterization of a strong mutant in Arabidopsis revealed that the protein is essential for plant viability, while a weak mutant produced dwarf, chlorotic plants that incorporated immature pre-16S ribosomal RNA into translating ribosomes. Physiological analysis of the mutant plants revealed smaller, but more numerous chloroplasts in the mesophyll cells, reduction of chlorophyllaandb, depletion of proplastids from the rib meristem and decreased photosynthetic electron transport rate and efficiency. Comparative RNA-sequencing and proteomic analysis of the weak mutant and wild-type plants revealed that various biotic stress-related, transcriptional regulation and post-transcriptional modification pathways were repressed in the mutant. Intriguingly, while nuclear- and chloroplast-encoded photosynthesis-related proteins were less abundant in the mutant, the corresponding transcripts were upregulated, suggesting an elaborate compensatory mechanism, potentially via differentially active retrograde signalling pathways. To conclude, this study reveals a new chloroplast ribosome assembly factor and outlines the transcriptomic and proteomic responses of the compensatory mechanism activated during decreased chloroplast function.Significance statementAtRsgA is an assembly factor necessary for maturation of the small subunit of the chloroplast ribosome. Depletion of AtRsgA leads to dwarfed, chlorotic plants and smaller, but more numerous chloroplasts. Large-scale transcriptomic and proteomic analysis revealed that chloroplast-encoded and - targeted proteins were less abundant, while the corresponding transcripts were upregulated in the mutant. We analyse the transcriptional responses of several retrograde signalling pathways to suggest a mechanism underlying this compensatory response.

Plastid protein biosynthesis occurs on bacterial-type 70S ribosomes consisting of a large (50S) and a small (30S) subunit. However, since many steps of ribosome biogenesis are not thermodynamically favorable at biological conditions, it requires many assembly factors. One group of assembly factors, circularly permuted GTPases, was implicated in 30S subunit maturation in E. coli, by a protein RsgA. RsgA orthologues are present in bacteria and plastid-containing species and in silico analysis revealed presence of a RsgA-like protein in Arabidopsis thaliana. To functionally characterize the Arabidopsis orthologue, two AtRsgA T-DNA insertion lines were analyzed in this study. The exon line (rsgA-e) led to embryo lethality, while the intron line (rsgA-i) caused severe dwarf, pale green phenotype. Further investigation of rsgA-i mutant line revealed defects in chloroplast biogenesis which led to increased number of chloroplasts, decreased chloroplast size, decreased air space between mesophyll cells and smaller shoot apical meristems, which showed unusual proplastid accumulation. Moreover, rsgA-i plants showed reduction in chlorophyll A and B content, decreased electron transport rate and photosynthetic efficiency. Further analyses revealed that the protein is involved in chloroplast 30S subunit maturation. Interestingly, we observed that while chloroplast-targeted and chloroplast-encoded proteins are generally downregulated in the mutant, a contrasting upregulation of the corresponding transcripts is observed, indicating an elaborate compensatory mechanism. To conclude, the study presented here reveals a ribosome assembly factor and a compensatory mechanism activated during impaired chloroplast function.

Marta Musiał