In recent years,multiple advances have been made in understanding the photosynthetic machinery in model organisms.Knowledge transfer to horticultural important fruit crops is challenging and time-consuming due to rest...In recent years,multiple advances have been made in understanding the photosynthetic machinery in model organisms.Knowledge transfer to horticultural important fruit crops is challenging and time-consuming due to restrictions in gene editing tools and prolonged life cycles.Here,we characterize a gene encoding a PetM domain-containing protein in tomato.The CRISPR/Cas9 knockout lines of the PetM showed impairment in the chloroplastic electron transport rate(ETR),reduced CO_(2) assimilation,and reduction of carotenoids and chlorophylls(Chl)under several light conditions.Further,growth-condition-dependent elevation or repression of Chl a/b ratios and de-epoxidation states were identified,underlining possible impairment compensation mechanisms.However,under low light and glasshouse conditions,there were basal levels in CO_(2) assimilation and ETR,indicating a potential role of the PetM domain in stabilizing the cytochrome b6f complex(Cb6f)under higher light irradiance and increasing its quantum efficiency.This suggests a potential evolutionary role in which this domain might stabilize the site of the Cb6f regulating ratios of cyclic and linear electron transport and its potential importance during the conquest of terrestrial ecosystems during which plants were exposed to higher irradiance.Finally,the results are discussed with regard to metabolism and their implication to photosynthesis from an agronomic perspective.展开更多
While it is estimated that global food production needs to double by 2050 to keep pace with demand, current crop production cannot meet this demand, and the situation is even more perilous given the stress burden plac...While it is estimated that global food production needs to double by 2050 to keep pace with demand, current crop production cannot meet this demand, and the situation is even more perilous given the stress burden placed on our agricultural systems by climate change (Wheeler and von Braun, 2013). Indeed, it is anticipated that a 2℃ rise during the growing season would result in yield losses of 3%–13% (Zhao et al., 2017). Thus, it is urgently needed to realign breeding strategies and rapidly develop climate-resilient crops that can achieve stable yields under both normal and heat stress conditions. One route toward improving yields, and to a lesser extent yield stability, has been achieved through considerable research effort optimizing internal nutrient allocation (Fernie et al., 2020). In this regard, plant organs are often classified as “source” or “sink,” with the former being net producers of photoassimilates, whereas the latter are net importers that either store or utilize photoassimilates, and sucrose is a crucial yield determinant (Ruan et al., 2012). Sucrose is transported from source to sink tissues via the phloem and supports growth of various sink organs, including roots, flowers, fruits, seeds, cotton fibers, and other storage organs (Lou et al., 2025). In the storage organs, sucrose is predominantly degraded into either glucose and fructose by invertases or UDP-glucose and fructose via the action of sucrose synthases (Ruan et al., 2012). Of these enzymes, cell wall invertases have been found to play a pivotal role;for example, in tomato this gene was mapped to a major quantitative trait locus for agronomic yield (Fridman et al., 2004). It has, furthermore, been demonstrated that cell wall invertases have been selected during the domestication of major crops, including tomato and rice (Wang et al., 2008;Tieman et al., 2017). That said, heat stress has been demonstrated to repress carbon partitioning to source organs, causing selective abortion of grains and ovaries and resulting in considerable yield losses (Ruan et al., 2012). While early efforts to mitigate this effect revolved around the overexpression of cell wall invertases, these were typically associated with severe yield penalties (von Schaewen et al., 1990). To circumvent this “strategic abandonment” in a recent study, Lou et al. (2025) developed a clever approach that adopted contemporary prime editing tools to rationally manipulate the expression of cell wall invertase in both fruit and cereal crops, resulting in considerably reduced yield losses following heat stress.展开更多
Dear Editors,Global maize yields are stagnating,with over 50% of China's growing areas experiencing yield plateaus(Gerber et al.,2024).Climate change significantly contributes to this stagnation(Tigchelaar et al.,...Dear Editors,Global maize yields are stagnating,with over 50% of China's growing areas experiencing yield plateaus(Gerber et al.,2024).Climate change significantly contributes to this stagnation(Tigchelaar et al.,2018;Rizzo et al.,2022).展开更多
Protein complexes are important for almost all biological processes.Hence,to fully understand how cells work,it is also necessary to characterize protein complexes and their dynamics in response to various cellular cu...Protein complexes are important for almost all biological processes.Hence,to fully understand how cells work,it is also necessary to characterize protein complexes and their dynamics in response to various cellular cues.Moreover,the dynamics of protein interaction play crucial roles in regulating the(dis)association of protein complexes and,in turn,regulating biological processes such as metabolism.Here,mitochondrial protein complexes were investigated by blue native PAGE and size-exclusion chromatography under conditions of oxidative stress in order to monitor their dynamic(dis)associations.Rearrangements of enzyme interactions and changes in protein complex abundance were observed in response to oxidative stress induced by menadione treatment.These included changes in enzymatic protein complexes involving g-amino butyric acid transaminase(GABA-T),D-ornithine aminotransferase(D-OAT),or proline dehydrogenase 1(POX1)that are expected to affect proline metabolism.Menadione treatment also affected interactions between several enzymes of the tricarboxylic acid(TCA)cycle and the abundance of complexes of the oxidative phosphorylation pathway.In addition,we compared the mitochondrial complexes of roots and shoots.Considerable differences between the two tissues were observed in the mitochondrial import/export apparatus,the formation of super-complexes in the oxidative phosphorylation pathway,and specific interactions between enzymes of the TCA cycle that we postulate may be related to the metabolic/energetic requirements of roots and shoots.展开更多
基金We would like to thank Dr.Micha Wijesingha Ahchige for guiding and giving advice for the CRISPR/Cas9 vector generation and Dr.Mark A.Schoettler and Dr.Ryo Yokohama for the scientific advices and discussions.Also thanks to Dr.Karin Köhl,the greenhouse team of theMax Planck Institute of Molecular Plant Physiology,for transforming and handling the plants.M.B.appreciates the finan-cial support of the International Max Planck Research School for Molecular Plant Sciences(IMPRS-MolPlant).The research fellow-ship granted by Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq-Brazil)to A.N.-N.is gratefully acknowledged.A.R.F.and S.A.acknowledge the European Union’s Horizon 2020 research and innovation programme,project PlantaSYST(SGA-CSA No.739582 under FPA No.664620)the BG05M2OP001-1.003-001-C01 projectfinanced by the European Regional Devel-opment Fund through the Bulgarian’Science and Education for Smart Growth’Operational Programme.S.A.acknowledges the EU Horizon 2020,call HORIZON-WIDERA-2022-TALENTS-01,project NatGenCrop(grant agreement No.101087091).
文摘In recent years,multiple advances have been made in understanding the photosynthetic machinery in model organisms.Knowledge transfer to horticultural important fruit crops is challenging and time-consuming due to restrictions in gene editing tools and prolonged life cycles.Here,we characterize a gene encoding a PetM domain-containing protein in tomato.The CRISPR/Cas9 knockout lines of the PetM showed impairment in the chloroplastic electron transport rate(ETR),reduced CO_(2) assimilation,and reduction of carotenoids and chlorophylls(Chl)under several light conditions.Further,growth-condition-dependent elevation or repression of Chl a/b ratios and de-epoxidation states were identified,underlining possible impairment compensation mechanisms.However,under low light and glasshouse conditions,there were basal levels in CO_(2) assimilation and ETR,indicating a potential role of the PetM domain in stabilizing the cytochrome b6f complex(Cb6f)under higher light irradiance and increasing its quantum efficiency.This suggests a potential evolutionary role in which this domain might stabilize the site of the Cb6f regulating ratios of cyclic and linear electron transport and its potential importance during the conquest of terrestrial ecosystems during which plants were exposed to higher irradiance.Finally,the results are discussed with regard to metabolism and their implication to photosynthesis from an agronomic perspective.
文摘While it is estimated that global food production needs to double by 2050 to keep pace with demand, current crop production cannot meet this demand, and the situation is even more perilous given the stress burden placed on our agricultural systems by climate change (Wheeler and von Braun, 2013). Indeed, it is anticipated that a 2℃ rise during the growing season would result in yield losses of 3%–13% (Zhao et al., 2017). Thus, it is urgently needed to realign breeding strategies and rapidly develop climate-resilient crops that can achieve stable yields under both normal and heat stress conditions. One route toward improving yields, and to a lesser extent yield stability, has been achieved through considerable research effort optimizing internal nutrient allocation (Fernie et al., 2020). In this regard, plant organs are often classified as “source” or “sink,” with the former being net producers of photoassimilates, whereas the latter are net importers that either store or utilize photoassimilates, and sucrose is a crucial yield determinant (Ruan et al., 2012). Sucrose is transported from source to sink tissues via the phloem and supports growth of various sink organs, including roots, flowers, fruits, seeds, cotton fibers, and other storage organs (Lou et al., 2025). In the storage organs, sucrose is predominantly degraded into either glucose and fructose by invertases or UDP-glucose and fructose via the action of sucrose synthases (Ruan et al., 2012). Of these enzymes, cell wall invertases have been found to play a pivotal role;for example, in tomato this gene was mapped to a major quantitative trait locus for agronomic yield (Fridman et al., 2004). It has, furthermore, been demonstrated that cell wall invertases have been selected during the domestication of major crops, including tomato and rice (Wang et al., 2008;Tieman et al., 2017). That said, heat stress has been demonstrated to repress carbon partitioning to source organs, causing selective abortion of grains and ovaries and resulting in considerable yield losses (Ruan et al., 2012). While early efforts to mitigate this effect revolved around the overexpression of cell wall invertases, these were typically associated with severe yield penalties (von Schaewen et al., 1990). To circumvent this “strategic abandonment” in a recent study, Lou et al. (2025) developed a clever approach that adopted contemporary prime editing tools to rationally manipulate the expression of cell wall invertase in both fruit and cereal crops, resulting in considerably reduced yield losses following heat stress.
基金supported by the National Key R&D Program of China(2021YFD1201300)the Major Science and Technology Projects in Biological Breeding(2023ZD04067)the Fundamental Research Funds for the Central Universities(2662025JGPY003).
文摘Dear Editors,Global maize yields are stagnating,with over 50% of China's growing areas experiencing yield plateaus(Gerber et al.,2024).Climate change significantly contributes to this stagnation(Tigchelaar et al.,2018;Rizzo et al.,2022).
基金supported by funding from the Max Planck Society(S.M.J.,A.G.,A.R.F.,and Y.Z.)the European Union’s Horizon 2020 research and innovation program,project PlantaSYST(SGA-CSA no.739582 under FPA no.664620)for supporting their researchfinancial support from the IMPRS-PMPG program.
文摘Protein complexes are important for almost all biological processes.Hence,to fully understand how cells work,it is also necessary to characterize protein complexes and their dynamics in response to various cellular cues.Moreover,the dynamics of protein interaction play crucial roles in regulating the(dis)association of protein complexes and,in turn,regulating biological processes such as metabolism.Here,mitochondrial protein complexes were investigated by blue native PAGE and size-exclusion chromatography under conditions of oxidative stress in order to monitor their dynamic(dis)associations.Rearrangements of enzyme interactions and changes in protein complex abundance were observed in response to oxidative stress induced by menadione treatment.These included changes in enzymatic protein complexes involving g-amino butyric acid transaminase(GABA-T),D-ornithine aminotransferase(D-OAT),or proline dehydrogenase 1(POX1)that are expected to affect proline metabolism.Menadione treatment also affected interactions between several enzymes of the tricarboxylic acid(TCA)cycle and the abundance of complexes of the oxidative phosphorylation pathway.In addition,we compared the mitochondrial complexes of roots and shoots.Considerable differences between the two tissues were observed in the mitochondrial import/export apparatus,the formation of super-complexes in the oxidative phosphorylation pathway,and specific interactions between enzymes of the TCA cycle that we postulate may be related to the metabolic/energetic requirements of roots and shoots.
