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Green organisms evolve O2via photosynthesis and consume by respiration. Net O2consumption only becomes dominant when photosynthesis is suppressed at night. Here, we show that green thylakoid membranes of Scots pine (Pinus sylvestris L) and Norway spruce (Picea abies) needles demonstrate strong O2consumption even in the presence of light when extremely low temperatures coincide with high solar irradiation during early spring. This phenomenon deviates from the general finding that photosynthetic organisms evolve O2upon illumination. By using different electron transport chain inhibitors, we showed that O2consumption occurred around photosystem (PS) I and correlated with higher abundance of flavodiiron (Flv) A protein in ES thylakoid membranes. Furthermore, by measuring P700 absorption changes, we separated different alternative electron flow pathways and demonstrated that electron scavenging from the acceptor-side of PSI via O2photoreduction is a major alternative pathway in ES. This photoprotection mechanism in vascular plants indicates that conifers have developed an adaptative evolution trajectory for growing in harsh environments.

The original version of this Article contained an error in Fig. 1g, h and l, in which the y axes were labelled ‘NPQ (1-Fm'/Fm)’. They should have been labelled ‘NPQ (Fm/Fm'-1)’. This has been corrected in the PDF and HTML versions of the Article.

Evergreen conifers in boreal forests can survive extremely cold (freezing) temperatures during long dark winter and fully recover during summer. A phenomenon called “sustained quenching” putatively provides photoprotection and enables their survival, but its precise molecular and physiological mechanisms are not understood. To unveil them, here we have analyzed seasonal adjustment of the photosynthetic machinery of Scots pine (Pinus sylvestris) trees by monitoring multi-year changes in weather, chlorophyll fluorescence, chloroplast ultrastructure, and changes in pigment-protein composition. Analysis of Photosystem II and Photosystem I performance parameters indicate that highly dynamic structural and functional seasonal rearrangements of the photosynthetic apparatus occur. Although several mechanisms might contribute to ‘sustained quenching’ of winter/early spring pine needles, time-resolved fluorescence analysis shows that extreme down-regulation of photosystem II activity along with direct energy transfer from photosystem II to photosystem I play a major role. This mechanism is enabled by extensive thylakoid destacking allowing for the mixing of PSII with PSI complexes. These two linked phenomena play crucial roles in winter acclimation and protection., Evergreen conifers rely on ‘sustained quenching’ to protect their photosynthetic machinery during long, cold winters. Here, Bag et al. show that direct energy transfer (spillover) from photosystem II to photosystem I triggered by loss of grana stacking in chloroplast is the major component of sustained quenching in Scots pine.

Evergreen conifers in boreal forests can survive extremely cold (freezing) temperatures during the long dark winter and fully recover during the summer. A phenomenon called ‘sustained quenching’ putatively provides photoprotection and enables their survival, but its precise molecular and physiological mechanisms are not understood. To unveil them, we have analyzed the seasonal adaptation of the photosynthetic machinery of Scots pine (Pinus sylvestris) trees by monitoring multi-year changes in weather, chlorophyll fluorescence, chloroplast ultrastructure, and changes in pigment-protein composition. Recorded Photosystem II and Photosystem I performance parameters indicate that highly dynamic structural and functional seasonal rearrangements of the photosynthetic apparatus occur. Although several mechanisms might contribute to ‘sustained quenching’ of winter/early spring pine needles, time-resolved fluorescence analysis shows that extreme down-regulation of photosystem II activity along with direct energy transfer from photosystem II to photosystem I plays a major role. This mechanism is enabled by extensive thylakoid destacking allowing for mixing of PSII with PSI complexes. These two linked phenomena play crucial roles in winter acclimation and protection.Graphical abstract

Введение. Дополнительное образование обладает высоким потенциалом влияния на музыкально-творческое развитие детей. Одной из интегративных форм образовательной деятельности является школьный театр, в рамках которого актуализируются разносторонние творческие способности обучающихся: музыкальные (вокальные, инструментальные), танцевальные, пластические, актерские, словесно-драматические и др. Цель – рассмотреть теоретико-методические основания развития музыкально-творческих способностей детей младшего школьного возраста в процессе театрализованной деятельности, осуществляемой в условиях дополнительного образования. Материал и методы. Для выявления состояния проблемы музыкально-творческого развития детей в условиях дополнительного образования и ее решения использовался метод анализа психолого-педагогической и методической литературы, позволивший разработать творческие задания для участников музыкально-театрального кружка. Результаты и обсуждение. В ходе исследования уточнены содержательные и структурные компоненты понятия «музыкально-творческие способности», включающие в себя общемузыкальные, специальные музыкальные (познавательные, исполнительские, творческие) и индивидуально-творческие способности детей (эмпатийность, артистизм, эмоциональность, образный характер мышления и др.). Подчеркивается, что музыкально-творческие способности – это комплекс личностных особенностей (мотивационной, эмоциональной, волевой, интеллектуальной и креативно-творческой сфер) и специальных способностей, необходимых для занятий искусством музыки. Методические рекомендации для педагогов описывают поэтапную организацию занятий в школьном театре (мотивационный, содержательный и процессуальный компоненты), наиболее эффективные методы музыкально-творческого развития обучающихся, исходя из возрастных и индивидуальных особенностей младших школьников, а также согласуясь с синтетической природой музыкально-театрального жанра и коллективной формой сотворчества педагога и учащихся. Заключение. Развитие музыкально-творческих способностей у учащихся начальных классов средствами школьного театра зависит от организации учебного процесса, основанной на комплексном применении творческих заданий, направленных на формирование отдельно каждой структурной составляющей данных способностей, а также на их синтез. Эффективной формой проведения занятий в школьном театре в условиях дополнительного образования детей являются репетиции музыкально-театрализованных представлений, в ходе которых происходит не только музыкально-творческое, но и общекультурное развитие личности обучающихся, становление коллектива единомышленников.Introduction. Additional education has a high potential to influence the musical and creative development of children. One of the integrative forms of educational activity is the school theater, in which the versatile creative abilities of students are updated: musical (vocal, instrumental), dance, plastic, acting, verbal and dramatic, etc. The purpose of the article is to consider the theoretical and methodological grounds for the development of musical and creative abilities of children of primary school age in the process of theatrical activities carried out in the conditions of additional education. Material and methods. To identify the status of the problem of musical-creative development of children in terms of further education and its solution used the method of analysis of psycho-pedagogical and methodological literature and empirical methods, allowing to develop and test creative task for the participants of the musical-theatre group. Results and discussion. The study clarifies the content and structural components of the concept of “musical and creative abilities”, including General musical, special musical (cognitive, performing, creative) and individual creative abilities of children (empathy, artistry, emotionality, imaginative nature of thinking, etc.). Methodical recommendations for teachers describe the phased organization of classes in the school theater (motivational, content and procedural components), the most effective methods of musical and creative development of students, based on the age and individual characteristics of younger students, as well as consistent with the synthetic nature of the musical theater genre and the collective form of co-creation of the teacher and students. Conclusion. The development of musical and creative abilities of primary school students by means of school theater depends on the organization of the educational process, based on the complex application of creative tasks aimed at the formation of each structural component of these abilities separately, as well as their synthesis. An effective form of instruction in school theater from the point of view of additional education of children is rehearsal of musical and theatrical performances, in which not only the musical, creative and cultural development of the personality of students takes place, the formation of a group of like-minded people.

The article introduces tolerance training in the ESL classroom as part of a broader paradigm of teaching culture and intercultural communication skills in the process of foreign language instruction. After a brief discussion of how tolerance is currently understood in Russia and in the world, the authors present tolerance as, firstly, one of the leading values in modern education and, secondly, as the basis of productive cross-cultural interaction. They conclude with an example of an ESL workshop that embodies the paradigm of culture-based language teaching and targets tolerance as its primary educational goal.

The PsbO protein is an essential extrinsic subunit of photosystem II, the pigment-protein complex responsible for light-driven water splitting. Water oxidation in photosystem II supplies electrons to the photosynthetic electron transfer chain and is accompanied by proton release and oxygen evolution. While the electron transfer steps in this process are well defined and characterized, the driving forces acting on the liberated protons, their dynamics and their destiny are all largely unknown. It was suggested that PsbO undergoes proton-induced conformational changes and forms hydrogen bond networks that ensure prompt proton removal from the catalytic site of water oxidation, i.e. the Mn

In oxygenic photosynthesis, light energy is stored in the form of chemical energy by converting CO2 and water into carbohydrates. The light-driven oxidation of water that provides the electrons and protons for the subsequent CO2 fixation takes place in photosystem II (PSII). Recent studies show that in higher plants, HCO3 – increases PSII activity by acting as a mobile acceptor of the protons produced by PSII. In the green alga Chlamydomonas reinhardtii, a luminal carbonic anhydrase, CrCAH3, was suggested to improve proton removal from PSII, possibly by rapid reformation of HCO3 – from CO2. In this study, we investigated the interplay between PSII and CrCAH3 by membrane inlet mass spectrometry and x-ray crystallography. Membrane inlet mass spectrometry measurements showed that CrCAH3 was most active at the slightly acidic pH values prevalent in the thylakoid lumen under illumination. Two crystal structures of CrCAH3 in complex with either acetazolamide or phosphate ions were determined at 2.6- and 2.7-Å resolution, respectively. CrCAH3 is a dimer at pH 4.1 that is stabilized by swapping of the N-terminal arms, a feature not previously observed in α-type carbonic anhydrases. The structure contains a disulfide bond, and redox titration of CrCAH3 function with dithiothreitol suggested a possible redox regulation of the enzyme. The stimulating effect of CrCAH3 and CO2/HCO3 – on PSII activity was demonstrated by comparing the flash-induced oxygen evolution pattern of wild-type and CrCAH3-less PSII preparations. We showed that CrCAH3 has unique structural features that allow this enzyme to maximize PSII activity at low pH and CO2 concentration., This work was supported by Solar Fuels at Umeå University, the Artificial Leaf Project Umeå (Knut and Alice Wallenberg’s Foundation), the Kempe Foundation, the Swedish Research Council (to J.M., G.S., and A.E.S.-E.), Energimyndigheten (to J.M.), and Stiftelsen Olle Engkvist Byggmästare (to A.E.S.-E.).