Dear Editor, The LATERAL ORGAN BOUNDARIES DOMAIN （LBD）/ ASYMMETRICLEAVES2-LIKE （ASL） genes （hereafter referred to as LBD） encode proteins containing a conserved plant-specific LOB domain and play roles in later...Dear Editor, The LATERAL ORGAN BOUNDARIES DOMAIN （LBD）/ ASYMMETRICLEAVES2-LIKE （ASL） genes （hereafter referred to as LBD） encode proteins containing a conserved plant-specific LOB domain and play roles in lateral organ development （Iwakawa et al., 2002; Shuai et al., 2002; Majer and Hochholdinger, 2011）. The LOB domain is approximately 100 amino acids in length and contains a conserved four-Cys motif （CX2CX6CX3C）, the Gly-Ala-Ser block （GAS）, and the leucine-zipper-like coiled-coil motif （LX6LX3LX6L） （Shuai et al., 2002）. The leucine-zipper-like coiled-coil motif in the LOB domain is predicted to function in protein dimerization. LOB, AS2, and LBD4 preferentially bind unique DNA sequences in electrophoretic mobility shift assays （EMSAs） （Husbands et al., 2007）. The LOB domain of AS2 cannot be functionally replaced by those of other members of the LOB family,展开更多
Subcellular organelles in eukaryotes are surrounded by lipid membranes.In an endomembrane system,vesicle trafficking is the primary mechanism for the delivery of organellar proteins to specific organelles.However,orga...Subcellular organelles in eukaryotes are surrounded by lipid membranes.In an endomembrane system,vesicle trafficking is the primary mechanism for the delivery of organellar proteins to specific organelles.However,organellar proteins for chloroplasts,mitochondria,the nucleus,and peroxisomes that are translated in the cytosol are directly imported into their target organelles.Chloroplasts are a plant-specific organelle with outer and inner envelope membranes,a dual-membrane structure that is similar to mitochondria.Interior chloroplast proteins translated by cytosolic ribosomes are thus translocated through TOC and TIC complexes(translocons in the outer and inner envelope of chloroplasts,respectively),with stromal ATPase motor proteins playing a critical role in pulling pre-proteins through these import channels.Over the last three decades,the identity and function of TOC/TIC components and stromal motor proteins have been actively investigated,which has shed light on the action mechanisms at a molecular level.However,there remains some disagreement over the exact composition of TIC complexes and genuine stromal motor proteins.In this review,we discuss recent findings on the mechanisms by which proteins are translocated through TOC/TIC complexes and discuss future prospects for this field of research.展开更多
Virus-induced gene silencing （VIGS） is a powerful genetic tool for rapid assessment of plant gene functions in the post-genomic era. Here, we successfully implemented a Tobacco Rattle Virus （TRV）-based VlGS system...Virus-induced gene silencing （VIGS） is a powerful genetic tool for rapid assessment of plant gene functions in the post-genomic era. Here, we successfully implemented a Tobacco Rattle Virus （TRV）-based VlGS system to study functions of genes involved in either primary or secondary cell wall formation in Nicotiana benthamiana plants. A 3-week post- VIGS time frame is sufficient to observe phenotypic alterations in the anatomical structure of stems and chemical composition of the primary and secondary cell walls. We used cell wall glycan-directed monoclonal antibodies to demonstrate that alteration of cell wall polymer synthesis during the secondary growth phase of VIGS plants has profound effects on the extractability of components from woody stem cell walls. Therefore, TRV-based VlGS together with cell wall component profiling methods provide a high-throughput gene discovery platform for studying plant cell wall formation from a bioenergy perspective.展开更多
The aerial parts of land plants are covered with cuticu- lar waxes that limit non-stomatal water loss and gaseous exchanges, and protect plants from ultraviolet radiation and pathogen attacks. They are composed of ver...The aerial parts of land plants are covered with cuticu- lar waxes that limit non-stomatal water loss and gaseous exchanges, and protect plants from ultraviolet radiation and pathogen attacks. They are composed of very-long-chain fatty acids （VLCFAs; C20 to C34） in addition to their deriva-tives, aldehydes, alkanes, primary and secondary alcohols, and wax esters. Due to their physical properties, such as solid-ity at room temperature and a translucency ranging from transparent to opaque, plant waxes have been used as raw materials in the production of cosmetics, detergents, plas-tics, soaps, paints, drugs, lubricants, and high-value renew-able fuels. Many genes involved in cuticular wax biosynthesis and export have been characterized by forward and reverse genetic approaches as well as by stem epidermis transcrip-tome analysis. The regulatory mechanisms of cuticular wax biosynthesis have been reported at the transcriptional, post- transcriptional, and translational levels. Recent advances in cuticular wax biosynthesis and its regulation are reviewed in this paper.展开更多
Formation of secondary wall requires coordinated transcrip- tional regulation of the genes involved in the biosynthesis of major secondary wall components （e.g. cellulose, hemicellu- lose, and lignin）. Even though m...Formation of secondary wall requires coordinated transcrip- tional regulation of the genes involved in the biosynthesis of major secondary wall components （e.g. cellulose, hemicellu- lose, and lignin）. Even though many aspects of plant biology have been extensively elucidated using various model spe- cies, our current understanding of secondary wall formation is limited.展开更多
Membrane-localized leucine-rich repeat receptor kinases(LRR-RKs)sense diverse extracellular signals,and coordinate and specify cellular functions in plants.However,functional understanding and identification of the ce...Membrane-localized leucine-rich repeat receptor kinases(LRR-RKs)sense diverse extracellular signals,and coordinate and specify cellular functions in plants.However,functional understanding and identification of the cellular signaling of most LRR-RKs remain a major challenge owing to their genetic redundancy,the lack of ligand information,and subtle phenotypes of LRR-RK overexpression.Here,we report an engineered rapamycin-inducible dimerization(RiD)receptor system that triggers a receptor-specific LRR-RK signaling independent of their cognate ligands or endogenous receptors.Using the RiD-receptors,we demonstrated that the rapamycin-mediated association of chimeric cytosolic kinase domains from the BRI1/BAK1 receptor/co-receptor,but not the BRI1/BRI1 or BAK1/BAK1 homodimer,is sufficient to activate downstream brassinosteroid signaling and physiological responses.Furthermore,we showed that the engineered RiD-FLS2/BAK1 could activate flagellin-22-mediated immune signaling and responses.Using the RiD system,we also identified the potential function of an unkmown orphan receptor in immune signaling and revealed the differential activities of SERK co-receptors of LRR-RKs.Our results indicate that the RiD method can serve as a synthetic biology tool for precise temporal manipulation of LRR-RK signaling and for understanding LRR-RK biology.展开更多
Dwindling supply and unpredictable price fluctuations of fossil fuels have necessitated a renewed worldwide search for alter- native fuels. Plant cell walls, rich in cellulose and hemicellulose, are actively pursued f...Dwindling supply and unpredictable price fluctuations of fossil fuels have necessitated a renewed worldwide search for alter- native fuels. Plant cell walls, rich in cellulose and hemicellulose, are actively pursued for their use in production of second-gen- eration biofuels. It has been envisioned that degradation of these carbohydrate polymers to their sugar monomer subu- nits （saccharification） will provide necessary substrates for their yeast-mediated fermentation to ethanol.展开更多
The chloroplast is a unique organelle in that it possesses an intra-organellar membrane-enclosed structure called thylakoid,which is central to photosynthesis.Thus,the timely expression and correct localization of thy...The chloroplast is a unique organelle in that it possesses an intra-organellar membrane-enclosed structure called thylakoid,which is central to photosynthesis.Thus,the timely expression and correct localization of thylakoid proteins are of utmost importance to plant growth and development(Lee et al.,2017;New et al.,2018).Biogenesis of thylakoid proteins is highly complex;they are encoded by two different genomes,nuclear and chloroplast genomes,and translated in the cytosol and chloroplasts,respectively.Nuclear-encoded thylakoid proteins are first imported into the stroma of chloroplasts before they are targeted to thylakoids.In the stroma,multiple sorting mechanisms exist to ensure import or insertion of thylakoid luminal or membrane proteins,respectively(Lee et al.,2017).Approximately 50%of thylakoid luminal proteins are imported through the cpTAT(chloroplast twin-arginine translocation)pathway,which is also present in bacteria and plant mitochondria(Cline,2015;Schafer et al.f 2020).展开更多
The rate of textile waste generation worldwide has increased dramatically due to a rise in clothing consumption and production.Here,conversion of cotton-based,colored cotton-based,and blended cotton-polyethylene terep...The rate of textile waste generation worldwide has increased dramatically due to a rise in clothing consumption and production.Here,conversion of cotton-based,colored cotton-based,and blended cotton-polyethylene terephthalate(PET)textile waste materials into value-added chemicals(bioethanol,sorbitol,lactic acid,terephthalic acid(TPA),and ethylene glycol(EG))via enzymatic hydrolysis and fermentation was investigated.In order to enhance the efficiency of enzymatic saccharification,effective pretreatment methods for each type of textile waste were developed,respectively.A high glucose yield of 99.1%was obtained from white cotton-based textile waste after NaOH pretreatment.Furthermore,the digestibility of the cellulose in colored cotton-based textile wastes was increased 1.38e1.75 times because of the removal of dye materials by HPAC-NaOH pretreatment.The blended cottonPET samples showed good hydrolysis efficiency following PET removal via NaOHeethanol pretreatment,with a glucose yield of 92.49%.The sugar content produced via enzymatic hydrolysis was then converted into key platform chemicals(bioethanol,sorbitol,and lactic acid)via fermentation or hydrogenation.The maximum ethanol yield was achieved with the white T-shirt sample(537 mL/kg substrate),which was 3.2,2.1,and 2.6 times higher than those obtained with rice straw,pine wood,and oak wood,respectively.Glucose was selectively converted into sorbitol and LA at a yield of 70%and 83.67%,respectively.TPA and EG were produced from blended cottonPET via NaOHeethanol pretreatment.The integrated biorefinery process proposed here demonstrates significant potential for valorization of textile waste.展开更多
Two-component signal transduction is commonly used as a stimulus-response coupling mechanism to allow organisms such as eubacteria, archea, and a few eukaryotes to sense and respond to changes in many different enviro...Two-component signal transduction is commonly used as a stimulus-response coupling mechanism to allow organisms such as eubacteria, archea, and a few eukaryotes to sense and respond to changes in many different environmental conditions （Stock et al., 2000）. Typically, the histidine protein kinase senses extracellular stimuli by autophosphorylation and transfers a phosphoryl group to the response regu- lator, resulting in activation of downstream proteins that elicit a specific response. In Arabidopsis plants, a multi-step two-component system is well established as a key element of plant hormone cytokinin signaling （To and Kieber, 2008）.展开更多
文摘Dear Editor, The LATERAL ORGAN BOUNDARIES DOMAIN （LBD）/ ASYMMETRICLEAVES2-LIKE （ASL） genes （hereafter referred to as LBD） encode proteins containing a conserved plant-specific LOB domain and play roles in lateral organ development （Iwakawa et al., 2002; Shuai et al., 2002; Majer and Hochholdinger, 2011）. The LOB domain is approximately 100 amino acids in length and contains a conserved four-Cys motif （CX2CX6CX3C）, the Gly-Ala-Ser block （GAS）, and the leucine-zipper-like coiled-coil motif （LX6LX3LX6L） （Shuai et al., 2002）. The leucine-zipper-like coiled-coil motif in the LOB domain is predicted to function in protein dimerization. LOB, AS2, and LBD4 preferentially bind unique DNA sequences in electrophoretic mobility shift assays （EMSAs） （Husbands et al., 2007）. The LOB domain of AS2 cannot be functionally replaced by those of other members of the LOB family,
基金supported by an NRF grant funded by the MSIT(grant NRF-2020R1A2C4002294)supported by a National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2019R1A2B5B03099982)。
文摘Subcellular organelles in eukaryotes are surrounded by lipid membranes.In an endomembrane system,vesicle trafficking is the primary mechanism for the delivery of organellar proteins to specific organelles.However,organellar proteins for chloroplasts,mitochondria,the nucleus,and peroxisomes that are translated in the cytosol are directly imported into their target organelles.Chloroplasts are a plant-specific organelle with outer and inner envelope membranes,a dual-membrane structure that is similar to mitochondria.Interior chloroplast proteins translated by cytosolic ribosomes are thus translocated through TOC and TIC complexes(translocons in the outer and inner envelope of chloroplasts,respectively),with stromal ATPase motor proteins playing a critical role in pulling pre-proteins through these import channels.Over the last three decades,the identity and function of TOC/TIC components and stromal motor proteins have been actively investigated,which has shed light on the action mechanisms at a molecular level.However,there remains some disagreement over the exact composition of TIC complexes and genuine stromal motor proteins.In this review,we discuss recent findings on the mechanisms by which proteins are translocated through TOC/TIC complexes and discuss future prospects for this field of research.
文摘Virus-induced gene silencing （VIGS） is a powerful genetic tool for rapid assessment of plant gene functions in the post-genomic era. Here, we successfully implemented a Tobacco Rattle Virus （TRV）-based VlGS system to study functions of genes involved in either primary or secondary cell wall formation in Nicotiana benthamiana plants. A 3-week post- VIGS time frame is sufficient to observe phenotypic alterations in the anatomical structure of stems and chemical composition of the primary and secondary cell walls. We used cell wall glycan-directed monoclonal antibodies to demonstrate that alteration of cell wall polymer synthesis during the secondary growth phase of VIGS plants has profound effects on the extractability of components from woody stem cell walls. Therefore, TRV-based VlGS together with cell wall component profiling methods provide a high-throughput gene discovery platform for studying plant cell wall formation from a bioenergy perspective.
文摘The aerial parts of land plants are covered with cuticu- lar waxes that limit non-stomatal water loss and gaseous exchanges, and protect plants from ultraviolet radiation and pathogen attacks. They are composed of very-long-chain fatty acids （VLCFAs; C20 to C34） in addition to their deriva-tives, aldehydes, alkanes, primary and secondary alcohols, and wax esters. Due to their physical properties, such as solid-ity at room temperature and a translucency ranging from transparent to opaque, plant waxes have been used as raw materials in the production of cosmetics, detergents, plas-tics, soaps, paints, drugs, lubricants, and high-value renew-able fuels. Many genes involved in cuticular wax biosynthesis and export have been characterized by forward and reverse genetic approaches as well as by stem epidermis transcrip-tome analysis. The regulatory mechanisms of cuticular wax biosynthesis have been reported at the transcriptional, post- transcriptional, and translational levels. Recent advances in cuticular wax biosynthesis and its regulation are reviewed in this paper.
文摘Formation of secondary wall requires coordinated transcrip- tional regulation of the genes involved in the biosynthesis of major secondary wall components （e.g. cellulose, hemicellu- lose, and lignin）. Even though many aspects of plant biology have been extensively elucidated using various model spe- cies, our current understanding of secondary wall formation is limited.
基金supported by grants from the Basic Research Lab Program(2020R1A4A2002901)Basic Science Research Program(2019R1A2C1003783)through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICTthe Next-Generation BioGreen 21 Program from Rural Development Administration,Republic of Korea(PJ01314801 and PJ013220),and Korea University.
文摘Membrane-localized leucine-rich repeat receptor kinases(LRR-RKs)sense diverse extracellular signals,and coordinate and specify cellular functions in plants.However,functional understanding and identification of the cellular signaling of most LRR-RKs remain a major challenge owing to their genetic redundancy,the lack of ligand information,and subtle phenotypes of LRR-RK overexpression.Here,we report an engineered rapamycin-inducible dimerization(RiD)receptor system that triggers a receptor-specific LRR-RK signaling independent of their cognate ligands or endogenous receptors.Using the RiD-receptors,we demonstrated that the rapamycin-mediated association of chimeric cytosolic kinase domains from the BRI1/BAK1 receptor/co-receptor,but not the BRI1/BRI1 or BAK1/BAK1 homodimer,is sufficient to activate downstream brassinosteroid signaling and physiological responses.Furthermore,we showed that the engineered RiD-FLS2/BAK1 could activate flagellin-22-mediated immune signaling and responses.Using the RiD system,we also identified the potential function of an unkmown orphan receptor in immune signaling and revealed the differential activities of SERK co-receptors of LRR-RKs.Our results indicate that the RiD method can serve as a synthetic biology tool for precise temporal manipulation of LRR-RK signaling and for understanding LRR-RK biology.
文摘Dwindling supply and unpredictable price fluctuations of fossil fuels have necessitated a renewed worldwide search for alter- native fuels. Plant cell walls, rich in cellulose and hemicellulose, are actively pursued for their use in production of second-gen- eration biofuels. It has been envisioned that degradation of these carbohydrate polymers to their sugar monomer subu- nits （saccharification） will provide necessary substrates for their yeast-mediated fermentation to ethanol.
基金a grant from the National Research Foundation(NRF)of Korea funded by the Ministry of Science and Information Technology(MSIT),Korea(no.2019R1A2B5B03099982)D.W.L.was supported by an NRF grant funded by the MSIT(grant NRF-2020R1A2C4002294)a grant from the Next-Generation BioGreen 21 Program(System and Synthetic Agrobiotech Center),Rural Development Administration,Republic of Korea(grant PJ01335801).
文摘The chloroplast is a unique organelle in that it possesses an intra-organellar membrane-enclosed structure called thylakoid,which is central to photosynthesis.Thus,the timely expression and correct localization of thylakoid proteins are of utmost importance to plant growth and development(Lee et al.,2017;New et al.,2018).Biogenesis of thylakoid proteins is highly complex;they are encoded by two different genomes,nuclear and chloroplast genomes,and translated in the cytosol and chloroplasts,respectively.Nuclear-encoded thylakoid proteins are first imported into the stroma of chloroplasts before they are targeted to thylakoids.In the stroma,multiple sorting mechanisms exist to ensure import or insertion of thylakoid luminal or membrane proteins,respectively(Lee et al.,2017).Approximately 50%of thylakoid luminal proteins are imported through the cpTAT(chloroplast twin-arginine translocation)pathway,which is also present in bacteria and plant mitochondria(Cline,2015;Schafer et al.f 2020).
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education NRF-2022R1A2C10028591140982119420101 and 2020R1I1A 1A01061751)supported by the IBCT project(2021-0083)funded by the Tan Tao Group(TTG),Vietnam.
文摘The rate of textile waste generation worldwide has increased dramatically due to a rise in clothing consumption and production.Here,conversion of cotton-based,colored cotton-based,and blended cotton-polyethylene terephthalate(PET)textile waste materials into value-added chemicals(bioethanol,sorbitol,lactic acid,terephthalic acid(TPA),and ethylene glycol(EG))via enzymatic hydrolysis and fermentation was investigated.In order to enhance the efficiency of enzymatic saccharification,effective pretreatment methods for each type of textile waste were developed,respectively.A high glucose yield of 99.1%was obtained from white cotton-based textile waste after NaOH pretreatment.Furthermore,the digestibility of the cellulose in colored cotton-based textile wastes was increased 1.38e1.75 times because of the removal of dye materials by HPAC-NaOH pretreatment.The blended cottonPET samples showed good hydrolysis efficiency following PET removal via NaOHeethanol pretreatment,with a glucose yield of 92.49%.The sugar content produced via enzymatic hydrolysis was then converted into key platform chemicals(bioethanol,sorbitol,and lactic acid)via fermentation or hydrogenation.The maximum ethanol yield was achieved with the white T-shirt sample(537 mL/kg substrate),which was 3.2,2.1,and 2.6 times higher than those obtained with rice straw,pine wood,and oak wood,respectively.Glucose was selectively converted into sorbitol and LA at a yield of 70%and 83.67%,respectively.TPA and EG were produced from blended cottonPET via NaOHeethanol pretreatment.The integrated biorefinery process proposed here demonstrates significant potential for valorization of textile waste.
文摘Two-component signal transduction is commonly used as a stimulus-response coupling mechanism to allow organisms such as eubacteria, archea, and a few eukaryotes to sense and respond to changes in many different environmental conditions （Stock et al., 2000）. Typically, the histidine protein kinase senses extracellular stimuli by autophosphorylation and transfers a phosphoryl group to the response regu- lator, resulting in activation of downstream proteins that elicit a specific response. In Arabidopsis plants, a multi-step two-component system is well established as a key element of plant hormone cytokinin signaling （To and Kieber, 2008）.
