The evolution of display backplane technologies has been driven by the relentless pursuit of higher form factor and superior performance coupled with lower power consumption.Current state-of-the-art backplane technolo...The evolution of display backplane technologies has been driven by the relentless pursuit of higher form factor and superior performance coupled with lower power consumption.Current state-of-the-art backplane technologies based on amorphous Si,poly Si,and IGZO,face challenges in meeting the requirements of next-generation displays,including larger dimensions,higher refresh rates,increased pixel density,greater brightness,and reduced power consumption.In this context,2D chalcogenides have emerged as promising candidates for thin-film transistors(TFTs)in display backplanes,offering advantages such as high mobility,low leakage current,mechanical robustness,and transparency.This comprehensive review explores the significance of 2D chalcogenides as materials for TFTs in next-generation display backplanes.We delve into the structural characteristics,electronic properties,and synthesis methods of 2D chalcogenides,emphasizing scalable growth strategies that are relevant to large-area display backplanes.Additionally,we discuss mechanical flexibility and strain engineering,crucial for the development of flexible displays.Performance enhancement strategies for 2D chalcogenide TFTs have been explored encompassing techniques in device engineering and geometry optimization,while considering scaling over a large area.Active-matrix implementation of 2D TFTs in various applications is also explored,benchmarking device performance on a large scale which is a necessary aspect of TFTs used in display backplanes.Furthermore,the latest development on the integration of 2D chalcogenide TFTs with different display technologies,such as OLED,quantum dot,and MicroLED displays has been reviewed in detail.Finally,challenges and opportunities in the field are discussed with a brief insight into emerging trends and research directions.展开更多
BACKGROUND Mesenchymal stem cells(MSCs)are promising candidates for regenerative therapy due to their self-renewal capability,multilineage differentiation potential,and immunomodulatory effects.The molecular character...BACKGROUND Mesenchymal stem cells(MSCs)are promising candidates for regenerative therapy due to their self-renewal capability,multilineage differentiation potential,and immunomodulatory effects.The molecular characteristics of MSCs are influenced by their location.Recently,epidural fat(EF)and EF-derived MSCs(EF-MSCs)have garnered attention due to their potential benefits to the spinal microenvironment and their high expression of neural SC markers.However,their clinical applications are limited due to cell senescence and limited accessibility of EF.Although many studies have attempted to establish an immortalized,stable SC line,the characteristics of immortalized EF-MSCs remain to be clarified.AIM To establish and analyze stable immortalized EF-MSCs.METHODS The phenotypes of EF-MSCs were analyzed using optical microscopy.Cell immortalization was performed using lentiviral vectors.The biomolecular characteristics of the cells were analyzed by immunoblotting,quantitative PCR,and proteomics.RESULTS The immortalized EF-MSCs demonstrated a significantly extended lifespan compared to the control group,with well-preserved adipogenic potential and SC surface marker expression.Introduction of human telomerase reverse transcriptase genes markedly increased the lifespan of EF-MSCs.Proteomics analysis revealed substantial increase in the expression of DNA replication pathway components in immortalized EF-MSCs.CONCLUSION Immortalized EF-MSCs exhibited significantly enhanced proliferative capacity,retained adipogenic potential,and upregulated the expression of DNA replication pathway components.展开更多
Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar f...Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar fuels.A surface-modified Ag@Ru-P25 photocatalyst with H_(2)O_(2) treatment was designed in this study to convert CO_(2) and H_(2)O vapor into highly selective CH4.Ru doping followed by Ag nanoparticles(NPs)cocatalyst deposition on P25(TiO_(2))enhances visible light absorption and charge separation,whereas H_(2)O_(2) treatment modifies the surface of the photocatalyst with hydroxyl(–OH)groups and promotes CO_(2) adsorption.High-resonance transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray absorption near-edge structure,and extended X-ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst,while thermogravimetric analysis,CO_(2) adsorption isotherm,and temperature programmed desorption study were performed to examine the significance of H_(2)O_(2) treatment in increasing CO_(2) reduction activity.The optimized Ag1.0@Ru1.0-P25 photocatalyst performed excellent CO_(2) reduction activity into CO,CH4,and C2H6 with a~95%selectivity of CH4,where the activity was~135 times higher than that of pristine TiO_(2)(P25).For the first time,this work explored the effect of H_(2)O_(2) treatment on the photocatalyst that dramatically increases CO_(2) reduction activity.展开更多
We recently read the study by Kayano et al on intracorporeal anastomosis(IA)for colon cancer,which assessed bacterial contamination and medium-term onco-logical outcomes and affirmed that IA is analogous to extracorpo...We recently read the study by Kayano et al on intracorporeal anastomosis(IA)for colon cancer,which assessed bacterial contamination and medium-term onco-logical outcomes and affirmed that IA is analogous to extracorporeal anastomosis in reducing intraperitoneal bacterial risk and achieving similar oncological results.Our commentary addresses gaps,particularly concerning bowel preparation and surgical site infections(SSIs),and highlights the need for comprehensive details on the bowel preparation methods that are currently employed,including mecha-nical bowel preparation,oral antibiotics(OA),their combination,and specific OA types.We emphasize the necessity for further analyses that investigate these me-thods and their correlation with SSI rates,to enhance clinical protocol guidance and optimize surgical outcomes.Such meticulous analyses are essential for refi-ning strategies to effectively mitigate SSI risk in colorectal surgeries.展开更多
Fe alloy composites reinforced with in-situ titanium carbide （TIC） particles were fabricated by reactive sintering using different reactant C/Ti ratios of 0.8, 0.9, 1 and 1.1 to investigate the microstructure and me...Fe alloy composites reinforced with in-situ titanium carbide （TIC） particles were fabricated by reactive sintering using different reactant C/Ti ratios of 0.8, 0.9, 1 and 1.1 to investigate the microstructure and mechanical properties ofin-situ TiC/Fe alloy composites. The microstructure showed that the in-situ syn- thesized TiC particles were spherical with a size of 1-3 }~m, irrespective of C/Ti ratio. The stoichiometry of in-situ TiC increased from 0.85 to 0.88 with increasing C/Ti ratio from 0.8 to 0.9, but remained almost unchanged for C/Ti ratios between 0.9 and 1.1 due to the same driving force for carbon diffusion in TiCx at the common sintering temperature. The in-situ TiC/Fe alloy composite with C[Ti ~ 0.9 showed improved mechanical properties compared with other C/Ti ratios because the presence of excess carbon （C/Ti = 1 and 1.1） resulted in unreacted carbon within the Fe alloy matrix, while insufficient carbon （C/Ti = 0.8） caused the depletion of carbon from the Fe alloy matrix, leading to a significant decrease in hardness. This study presents that the maximized hardness and superior strength of in-situ TiC/Fe alloy composites can be achieved by microstructure control and stoichiometric analysis of the in-situ synthesized TiC par- ticles, while maintaining the ductility of the composites, compared to those of the unreinforced Fe alloy. Therefore, we anticipate that the in-situ synthesized TiC/Fe alloy composites with enhanced mechanical properties have great potential in cutting tool, mold and roller material applications.展开更多
Plants possess both types of endosymbiotic organelles, chloroplasts and mitochondria. Transit peptides and presequences function as signal sequences for specific import into chloroplasts and mitochondria, respectively...Plants possess both types of endosymbiotic organelles, chloroplasts and mitochondria. Transit peptides and presequences function as signal sequences for specific import into chloroplasts and mitochondria, respectively. However, how these highly similar signal sequences confer the protein import specificity remains elusive. Here, we show that mitochondrial- or chloroplast-specific import involves two distinct steps, specificity determination and translocation across envelopes, which are mediated by the N-terminal regions and functionally interchangeable C-terminal regions, respectively, of transit peptides and presequences. A domain harboring multiple-arginine and hydrophobic sequence motifs in the N-terminal regions of presequences was identified as the mitochondrial specificity factor. The presence of this domain and the absence of arginine residues in the N-terminal regions of otherwise common targeting signals confers specificity of protein import into mitochondria and chloroplasts, respectively. AtToc159, a chloroplast import receptor, also contributes to determining chloroplast import specificity. We propose that common ancestral sequences were functionalized into mitochondrial- and chloroplast-specific signal sequences by the presence and absence, respectively, of multiple-arginine and hydrophobic sequence motifs in the N-terminal region.展开更多
Rhizosphere acidification is essential for iron （Fe） uptake into plant roots. Plasma membrane （PM） H＊-ATPases play key roles in rhizosphere acidification. However, it is not fully understood how PM H＋-ATPase act...Rhizosphere acidification is essential for iron （Fe） uptake into plant roots. Plasma membrane （PM） H＊-ATPases play key roles in rhizosphere acidification. However, it is not fully understood how PM H＋-ATPase activity is regulated to enhance root Fe uptake under Fe-deficient conditions. Here, we present evidence that cytochrome b5 reductase 1 （CBR1） increases the levels of unsaturated fatty acids, which stimulate PM H＋-ATPase activity and thus lead to rhizosphere acidification. CBRl-overexpressing （CBRI-OX） Arabidopsis thaliana plants had higher levels of unsaturated fatty acids （18：2 and 18：3）, higher PM H＊-ATPase activity, and lower rhizosphere pH than wild-type plants. By contrast, cbrl loss-of-function mutant plants showed lower levels of unsaturated fatty acids and lower PM H＊-ATPase activity but higher rhizosphere pH. Reduced PM H＊-ATPase activity in cbrl could be restored in vitro by addition of unsatu- rated fatty acids. Transcript levels of CBR1, fatty acids desaturase 2 （FAD2）, and fatty acids desaturase 3 （FAD3） were increased under Fe-deficient conditions. We propose that CBR1 has a crucial role in increasing the levels of unsaturated fatty acids, which activate the PM H＊-ATPase and thus reduce rhizosphere pH. This reaction cascade ultimately promotes root Fe uptake.展开更多
Aquaporin （AQP） is a water channel protein found in various subcellular membranes of both prokaryotic and eukaryotic cells. The physiological functions of AQPs have been elucidated in many organisms. However, unders...Aquaporin （AQP） is a water channel protein found in various subcellular membranes of both prokaryotic and eukaryotic cells. The physiological functions of AQPs have been elucidated in many organisms. However, understanding their biogenesis remains elusive, particularly regarding how they assemble into tetramers. Here, we investigated the amino acid residues involved in the tetramer formation of the Arabidopsis plasma membrane AQP AtPIP2;1 using extensive amino acid substitution mutagenesis. The mutant proteins V41A/ E44A, F51A/L52A, F87A/191A, F92A/193A, V95A/Y96A, and H216A/L217A, harboring alanine substitutions in the transmembrane （TM） helices of AtPIP2;1 polymerized into multiple oligomeric complexes with a vari- able number of subunits greater than four. Moreover, these mutant proteins failed to traffic to the plasma membrane, instead of accumulating in the endoplasmic reticulum （ER）. Structure-based modeling revealed that these residues are largely involved in interactions between TM helices within monomers. These results suggest that inter-TM interactions occurring both within and between monomers play crucial roles in tetramer formation in the AtPIP2;1 complex. Moreover, the assembly of AtPIP2;1 tetramers is critical for their trafficking from the ER to the plasma membrane, as well as water permeability.展开更多
Protein biogenesis is a complex process,and complexity is greatly increased in eukaryotic cells through specific targeting of proteins to different organelles.To direct targeting,organellar proteins carry an organelle...Protein biogenesis is a complex process,and complexity is greatly increased in eukaryotic cells through specific targeting of proteins to different organelles.To direct targeting,organellar proteins carry an organelle-specific targeting signal for recognition by organelle-specific import machinery.However,the situation is confusing for transmembrane domain(TMD)-containing signalanchored(SA)proteins of various organelles because TMDs function as an endoplasmic reticulum(ER)targeting signal.Although ER targeting of SA proteins is well understood,how they are targeted to mitochondria and chloroplasts remains elusive.Here,we investigated how the targeting specificity of SA proteins is determined for specific targeting to mitochondria and chloroplasts.Mitochondrial targeting requires multiple motifs around and within TMDs:a basic residue and an arginine-rich region flanking the N-and C-termini of TMDs,respectively,and an aromatic residue in the C-terminal side of the TMD that specify mitochondrial targeting in an additive manner.These motifs play a role in slowing down the elongation speed during translation,thereby ensuring mitochondrial targeting in a cotranslational manner.By contrast,the absence of any of these motifs individually or together causes at varying degrees chloroplast targeting that occurs in a post-translational manner.展开更多
基金supported in part by the National Research Foundation of Korea Grant Number:RS-2024-00448809National Research Foundation of Korea Grant Number:RS-2025-00517255+1 种基金National Research Foundation of Korea Grant Number:No.2021M3H4A1A02056037supported by Basic Science Research Program through the National Research Foundation of Korean(NRF)funded by the Ministry of Education(2020R1A6A1A03040516).
文摘The evolution of display backplane technologies has been driven by the relentless pursuit of higher form factor and superior performance coupled with lower power consumption.Current state-of-the-art backplane technologies based on amorphous Si,poly Si,and IGZO,face challenges in meeting the requirements of next-generation displays,including larger dimensions,higher refresh rates,increased pixel density,greater brightness,and reduced power consumption.In this context,2D chalcogenides have emerged as promising candidates for thin-film transistors(TFTs)in display backplanes,offering advantages such as high mobility,low leakage current,mechanical robustness,and transparency.This comprehensive review explores the significance of 2D chalcogenides as materials for TFTs in next-generation display backplanes.We delve into the structural characteristics,electronic properties,and synthesis methods of 2D chalcogenides,emphasizing scalable growth strategies that are relevant to large-area display backplanes.Additionally,we discuss mechanical flexibility and strain engineering,crucial for the development of flexible displays.Performance enhancement strategies for 2D chalcogenide TFTs have been explored encompassing techniques in device engineering and geometry optimization,while considering scaling over a large area.Active-matrix implementation of 2D TFTs in various applications is also explored,benchmarking device performance on a large scale which is a necessary aspect of TFTs used in display backplanes.Furthermore,the latest development on the integration of 2D chalcogenide TFTs with different display technologies,such as OLED,quantum dot,and MicroLED displays has been reviewed in detail.Finally,challenges and opportunities in the field are discussed with a brief insight into emerging trends and research directions.
文摘BACKGROUND Mesenchymal stem cells(MSCs)are promising candidates for regenerative therapy due to their self-renewal capability,multilineage differentiation potential,and immunomodulatory effects.The molecular characteristics of MSCs are influenced by their location.Recently,epidural fat(EF)and EF-derived MSCs(EF-MSCs)have garnered attention due to their potential benefits to the spinal microenvironment and their high expression of neural SC markers.However,their clinical applications are limited due to cell senescence and limited accessibility of EF.Although many studies have attempted to establish an immortalized,stable SC line,the characteristics of immortalized EF-MSCs remain to be clarified.AIM To establish and analyze stable immortalized EF-MSCs.METHODS The phenotypes of EF-MSCs were analyzed using optical microscopy.Cell immortalization was performed using lentiviral vectors.The biomolecular characteristics of the cells were analyzed by immunoblotting,quantitative PCR,and proteomics.RESULTS The immortalized EF-MSCs demonstrated a significantly extended lifespan compared to the control group,with well-preserved adipogenic potential and SC surface marker expression.Introduction of human telomerase reverse transcriptase genes markedly increased the lifespan of EF-MSCs.Proteomics analysis revealed substantial increase in the expression of DNA replication pathway components in immortalized EF-MSCs.CONCLUSION Immortalized EF-MSCs exhibited significantly enhanced proliferative capacity,retained adipogenic potential,and upregulated the expression of DNA replication pathway components.
基金supported by the Ministry of Science and ICT in Korea(2021R1A2C2009459)X-ray absorption spectra were obtained from Pohang Accelerator Laboratory(PAL)10C beamlinesupported by the US Department of Energy,Office of Science,Office of Advanced Scientific Computing Research,and Scientific Discovery through Advanced Computing(SciDAC)program under Award Number DE-SC0022209.
文摘Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar fuels.A surface-modified Ag@Ru-P25 photocatalyst with H_(2)O_(2) treatment was designed in this study to convert CO_(2) and H_(2)O vapor into highly selective CH4.Ru doping followed by Ag nanoparticles(NPs)cocatalyst deposition on P25(TiO_(2))enhances visible light absorption and charge separation,whereas H_(2)O_(2) treatment modifies the surface of the photocatalyst with hydroxyl(–OH)groups and promotes CO_(2) adsorption.High-resonance transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray absorption near-edge structure,and extended X-ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst,while thermogravimetric analysis,CO_(2) adsorption isotherm,and temperature programmed desorption study were performed to examine the significance of H_(2)O_(2) treatment in increasing CO_(2) reduction activity.The optimized Ag1.0@Ru1.0-P25 photocatalyst performed excellent CO_(2) reduction activity into CO,CH4,and C2H6 with a~95%selectivity of CH4,where the activity was~135 times higher than that of pristine TiO_(2)(P25).For the first time,this work explored the effect of H_(2)O_(2) treatment on the photocatalyst that dramatically increases CO_(2) reduction activity.
文摘We recently read the study by Kayano et al on intracorporeal anastomosis(IA)for colon cancer,which assessed bacterial contamination and medium-term onco-logical outcomes and affirmed that IA is analogous to extracorporeal anastomosis in reducing intraperitoneal bacterial risk and achieving similar oncological results.Our commentary addresses gaps,particularly concerning bowel preparation and surgical site infections(SSIs),and highlights the need for comprehensive details on the bowel preparation methods that are currently employed,including mecha-nical bowel preparation,oral antibiotics(OA),their combination,and specific OA types.We emphasize the necessity for further analyses that investigate these me-thods and their correlation with SSI rates,to enhance clinical protocol guidance and optimize surgical outcomes.Such meticulous analyses are essential for refi-ning strategies to effectively mitigate SSI risk in colorectal surgeries.
基金supported by the Ministry of Trade,Industry&Energy(MOTIE,Korea)under Industrial Technology Innovation Program.No.10046591,‘Development of TiC reinforced metal matrix composite fabricated by in-situ liquid forming for tool steel’
文摘Fe alloy composites reinforced with in-situ titanium carbide （TIC） particles were fabricated by reactive sintering using different reactant C/Ti ratios of 0.8, 0.9, 1 and 1.1 to investigate the microstructure and mechanical properties ofin-situ TiC/Fe alloy composites. The microstructure showed that the in-situ syn- thesized TiC particles were spherical with a size of 1-3 }~m, irrespective of C/Ti ratio. The stoichiometry of in-situ TiC increased from 0.85 to 0.88 with increasing C/Ti ratio from 0.8 to 0.9, but remained almost unchanged for C/Ti ratios between 0.9 and 1.1 due to the same driving force for carbon diffusion in TiCx at the common sintering temperature. The in-situ TiC/Fe alloy composite with C[Ti ~ 0.9 showed improved mechanical properties compared with other C/Ti ratios because the presence of excess carbon （C/Ti = 1 and 1.1） resulted in unreacted carbon within the Fe alloy matrix, while insufficient carbon （C/Ti = 0.8） caused the depletion of carbon from the Fe alloy matrix, leading to a significant decrease in hardness. This study presents that the maximized hardness and superior strength of in-situ TiC/Fe alloy composites can be achieved by microstructure control and stoichiometric analysis of the in-situ synthesized TiC par- ticles, while maintaining the ductility of the composites, compared to those of the unreinforced Fe alloy. Therefore, we anticipate that the in-situ synthesized TiC/Fe alloy composites with enhanced mechanical properties have great potential in cutting tool, mold and roller material applications.
文摘Plants possess both types of endosymbiotic organelles, chloroplasts and mitochondria. Transit peptides and presequences function as signal sequences for specific import into chloroplasts and mitochondria, respectively. However, how these highly similar signal sequences confer the protein import specificity remains elusive. Here, we show that mitochondrial- or chloroplast-specific import involves two distinct steps, specificity determination and translocation across envelopes, which are mediated by the N-terminal regions and functionally interchangeable C-terminal regions, respectively, of transit peptides and presequences. A domain harboring multiple-arginine and hydrophobic sequence motifs in the N-terminal regions of presequences was identified as the mitochondrial specificity factor. The presence of this domain and the absence of arginine residues in the N-terminal regions of otherwise common targeting signals confers specificity of protein import into mitochondria and chloroplasts, respectively. AtToc159, a chloroplast import receptor, also contributes to determining chloroplast import specificity. We propose that common ancestral sequences were functionalized into mitochondrial- and chloroplast-specific signal sequences by the presence and absence, respectively, of multiple-arginine and hydrophobic sequence motifs in the N-terminal region.
文摘Rhizosphere acidification is essential for iron （Fe） uptake into plant roots. Plasma membrane （PM） H＊-ATPases play key roles in rhizosphere acidification. However, it is not fully understood how PM H＋-ATPase activity is regulated to enhance root Fe uptake under Fe-deficient conditions. Here, we present evidence that cytochrome b5 reductase 1 （CBR1） increases the levels of unsaturated fatty acids, which stimulate PM H＋-ATPase activity and thus lead to rhizosphere acidification. CBRl-overexpressing （CBRI-OX） Arabidopsis thaliana plants had higher levels of unsaturated fatty acids （18：2 and 18：3）, higher PM H＊-ATPase activity, and lower rhizosphere pH than wild-type plants. By contrast, cbrl loss-of-function mutant plants showed lower levels of unsaturated fatty acids and lower PM H＊-ATPase activity but higher rhizosphere pH. Reduced PM H＊-ATPase activity in cbrl could be restored in vitro by addition of unsatu- rated fatty acids. Transcript levels of CBR1, fatty acids desaturase 2 （FAD2）, and fatty acids desaturase 3 （FAD3） were increased under Fe-deficient conditions. We propose that CBR1 has a crucial role in increasing the levels of unsaturated fatty acids, which activate the PM H＊-ATPase and thus reduce rhizosphere pH. This reaction cascade ultimately promotes root Fe uptake.
文摘Aquaporin （AQP） is a water channel protein found in various subcellular membranes of both prokaryotic and eukaryotic cells. The physiological functions of AQPs have been elucidated in many organisms. However, understanding their biogenesis remains elusive, particularly regarding how they assemble into tetramers. Here, we investigated the amino acid residues involved in the tetramer formation of the Arabidopsis plasma membrane AQP AtPIP2;1 using extensive amino acid substitution mutagenesis. The mutant proteins V41A/ E44A, F51A/L52A, F87A/191A, F92A/193A, V95A/Y96A, and H216A/L217A, harboring alanine substitutions in the transmembrane （TM） helices of AtPIP2;1 polymerized into multiple oligomeric complexes with a vari- able number of subunits greater than four. Moreover, these mutant proteins failed to traffic to the plasma membrane, instead of accumulating in the endoplasmic reticulum （ER）. Structure-based modeling revealed that these residues are largely involved in interactions between TM helices within monomers. These results suggest that inter-TM interactions occurring both within and between monomers play crucial roles in tetramer formation in the AtPIP2;1 complex. Moreover, the assembly of AtPIP2;1 tetramers is critical for their trafficking from the ER to the plasma membrane, as well as water permeability.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022R1A2C1091844)。
文摘Protein biogenesis is a complex process,and complexity is greatly increased in eukaryotic cells through specific targeting of proteins to different organelles.To direct targeting,organellar proteins carry an organelle-specific targeting signal for recognition by organelle-specific import machinery.However,the situation is confusing for transmembrane domain(TMD)-containing signalanchored(SA)proteins of various organelles because TMDs function as an endoplasmic reticulum(ER)targeting signal.Although ER targeting of SA proteins is well understood,how they are targeted to mitochondria and chloroplasts remains elusive.Here,we investigated how the targeting specificity of SA proteins is determined for specific targeting to mitochondria and chloroplasts.Mitochondrial targeting requires multiple motifs around and within TMDs:a basic residue and an arginine-rich region flanking the N-and C-termini of TMDs,respectively,and an aromatic residue in the C-terminal side of the TMD that specify mitochondrial targeting in an additive manner.These motifs play a role in slowing down the elongation speed during translation,thereby ensuring mitochondrial targeting in a cotranslational manner.By contrast,the absence of any of these motifs individually or together causes at varying degrees chloroplast targeting that occurs in a post-translational manner.
