Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morpho...Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morphological features of PCD have been found in the developing starchy endosperm cells, e.g. nucleus deformation, chromatin condensation, nuclear envelope disruption, and nuclear matrix leakage. DNA ladder displayed a smear of large DNA fragments from nucleus and evident bands of small DNA fragments (140-180 bp) from both nucleus and cytoplasm. In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, amyloplast, and mitochondrion, maintained their metabolic functions for a longer time. Seed reserves were continually synthesized and accumulated in the starchy endosperm cells despite the nucleus degradation during the PCD process. These results suggest that starchy endosperm cells remain active during reserve material synthesis and accumulation in the PCD process. The specific relationships between nucleus and cytoplasm in the developing endosperm cells and the morphological changes of nucleus in the endosperm PCD process were also discussed.展开更多
Morphological variations of the nucleus in starchy endosperm cell were observed by theelectron-transmisson microscope during endosperm development in rice. Along with thedevelopment of the starchy endosperm, the nucle...Morphological variations of the nucleus in starchy endosperm cell were observed by theelectron-transmisson microscope during endosperm development in rice. Along with thedevelopment of the starchy endosperm, the nuclei of the cells showed chromatin condensation,the typical feature of programmed cell death (PCD). The nuclei also showed nucleusdeformation, disruption of nuclear envelope, nucleoplasm leaking into the cytoplasm andnucleus disintegration resulting in nuclear residue formation. From the nucleus deformationto the nucleus disintegration, the morphological changes of the nucleus were orderlyprogressive. This indicated that the cell death of starchy endosperm in rice wasprogrammed cell death. Evans Blue staining observation showed that the cell death wasinitially detected in the central part of starchy endosperm in rice, then expandedoutward. The activities of superoxide dismutase (SOD) and catalase (CAT) in rice starchyendosperm both descended continuously as development progressed. The analysis of DNA ofrice starchy endosperm did not show the presence of DNA laddering. The above resultsshowed that the cell death of starchy endosperm in rice was a special form of PCD.展开更多
Nonalcoholic fatty liver disease(NAFLD)is a high-incidence lipid disorder that affects more than a quarter of the population worldwide,and dietary intervention is the recognized treatment.Starch is the main component ...Nonalcoholic fatty liver disease(NAFLD)is a high-incidence lipid disorder that affects more than a quarter of the population worldwide,and dietary intervention is the recognized treatment.Starch is the main component of staple foods that are consumed daily,and the effects,metabolic pathway,and molecular mechanism of starch in the context of NAFLD remain unclear.Our study showed that a high-starch carbohydrate diet(HCD)led to the occurrence and exacerbation of NAFLD in mice.Transcriptomics and metabonomic analyses showed that the increased fatty acid influx mediated by NADPH oxidase 2(NOX2)exacerbated NAFLD.Knocking down NOX2 specifically alleviated HCD-induced NAFLD in vivo and in vitro.Moreover,the large amounts of ROS produced by NOX2 further exacerbated insulin resistance and increased lipolysis in perirenal white adipose tissue(periWAT),thereby providing fatty acids for hepatic lipid synthesis.In addition,the interaction between AMPKα1 and p47phox was the pathway that mediated the high expression of NOX2 induced by a HCD.Our study systematically demonstrated the effect of a HCD on NAFLD.Elevated fatty acid influx is a unique molecular regulatory pathway that mediates HCD-induced NAFLD exacerbation,which is different from the effect of simple sugars.Additionally,NOX2 was suggested to be a specific and effective drug target for NAFLD.展开更多
Mushrooms contain multiple bioactive compounds of which dietary fibre is a representative type.Fortification of extracted or naturally derived dietary fibre in staple starchy foods constitutes a strategy to increase f...Mushrooms contain multiple bioactive compounds of which dietary fibre is a representative type.Fortification of extracted or naturally derived dietary fibre in staple starchy foods constitutes a strategy to increase fibre intake in terms of cardiovascular disease and other metabolic diseases.Food matrix is viewed as a physical domain containing nutrients in which interactions and behaviours are different from those in isolation or free state.The nutritional effect of mushrooms'addition in the starchy food matrix is reviewed together with the alterations of cooking properties.Prospective studies include nutrients bioaccessibility due to the interfere of dietary fibres in consideration of their types and quality.The future approach to shaping microbial colonisation in the digestive tract through metabolites such as short-chain fatty acids from dietary fibres is required to sustain host physiology and health.展开更多
Dear Editor,Traditionally,the consumption of milled rice(starchy endosperm) as a staple food mainly provides calories for human society,and the lack of many important nutrients in such processed grains has led to maln...Dear Editor,Traditionally,the consumption of milled rice(starchy endosperm) as a staple food mainly provides calories for human society,and the lack of many important nutrients in such processed grains has led to malnutrition in rice-consuming regions worldwide(United Nations System Standing Committee on Nutrition,2004).展开更多
Identifying and segmenting the vitreous and starchy endosperm of maize kernels is essential for texture analysis.However,the complex internal structure of maize kernels presents several challenges.In CT(computed tomog...Identifying and segmenting the vitreous and starchy endosperm of maize kernels is essential for texture analysis.However,the complex internal structure of maize kernels presents several challenges.In CT(computed tomog-raphy)images,the pixel intensity differences between the vitreous and starchy endosperm regions in maize kernel CT images are not distinct,potentially leading to low segmentation accuracy or oversegmentation.Moreover,the blurred edges between the vitreous and starchy endosperm make segmentation difficult,often resulting in jagged segmentation outcomes.We propose a deep learning-based CT image analysis pipeline to examine the internal structure of maize seeds.First,CT images are acquired using a multislice CT scanner.To improve the efficiency of maize kernel CT imaging,a batch scanning method is used.Individual kernels are accurately segmented from batch-scanned CT images using the Canny algorithm.Second,we modify the conventional architecture for high-quality segmentation of the vitreous and starchy endosperm in maize kernels.The conventional U-Net is modified by integrating the CBAM(convolutional block attention module)mechanism in the encoder and the SE(squeeze-and-excitation attention)mechanism in the decoder,as well as by using the focal-Tversky loss function instead of the Dice loss,and the boundary smoothing term is weighted as an additional loss term,named CSFTU-Net.The experimental results show that the CSFTU-Net model significantly improves the ability of segmenting vitreous and starchy endosperm.Finally,a segmented mask-based method is proposed to extract phenotype parameters of maize kernel texture,including the volume of the kernel(V),volume of the vitreous endosperm(VV),volume of starchy endosperm(SV),and ratios over their respective total kernel volumes(W/V and SV/V).The proposed pipeline facilitates the nondestructive quantification of the internal structure of maize kernels,offering valuable insights for maize breeding and processing.展开更多
文摘Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morphological features of PCD have been found in the developing starchy endosperm cells, e.g. nucleus deformation, chromatin condensation, nuclear envelope disruption, and nuclear matrix leakage. DNA ladder displayed a smear of large DNA fragments from nucleus and evident bands of small DNA fragments (140-180 bp) from both nucleus and cytoplasm. In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, amyloplast, and mitochondrion, maintained their metabolic functions for a longer time. Seed reserves were continually synthesized and accumulated in the starchy endosperm cells despite the nucleus degradation during the PCD process. These results suggest that starchy endosperm cells remain active during reserve material synthesis and accumulation in the PCD process. The specific relationships between nucleus and cytoplasm in the developing endosperm cells and the morphological changes of nucleus in the endosperm PCD process were also discussed.
基金supported by the National Natural Science Foundation of China(30070363)the Foundation for Doctorate Research of Ministry of Education,China(200005041).
文摘Morphological variations of the nucleus in starchy endosperm cell were observed by theelectron-transmisson microscope during endosperm development in rice. Along with thedevelopment of the starchy endosperm, the nuclei of the cells showed chromatin condensation,the typical feature of programmed cell death (PCD). The nuclei also showed nucleusdeformation, disruption of nuclear envelope, nucleoplasm leaking into the cytoplasm andnucleus disintegration resulting in nuclear residue formation. From the nucleus deformationto the nucleus disintegration, the morphological changes of the nucleus were orderlyprogressive. This indicated that the cell death of starchy endosperm in rice wasprogrammed cell death. Evans Blue staining observation showed that the cell death wasinitially detected in the central part of starchy endosperm in rice, then expandedoutward. The activities of superoxide dismutase (SOD) and catalase (CAT) in rice starchyendosperm both descended continuously as development progressed. The analysis of DNA ofrice starchy endosperm did not show the presence of DNA laddering. The above resultsshowed that the cell death of starchy endosperm in rice was a special form of PCD.
基金financially supported by grants from the National Natural Science Foundation of China(8217087381871095)+1 种基金the National Key R&D Program of China(2018YFC2000304)the Tsinghua University Spring Breeze Fund(20211080005).
文摘Nonalcoholic fatty liver disease(NAFLD)is a high-incidence lipid disorder that affects more than a quarter of the population worldwide,and dietary intervention is the recognized treatment.Starch is the main component of staple foods that are consumed daily,and the effects,metabolic pathway,and molecular mechanism of starch in the context of NAFLD remain unclear.Our study showed that a high-starch carbohydrate diet(HCD)led to the occurrence and exacerbation of NAFLD in mice.Transcriptomics and metabonomic analyses showed that the increased fatty acid influx mediated by NADPH oxidase 2(NOX2)exacerbated NAFLD.Knocking down NOX2 specifically alleviated HCD-induced NAFLD in vivo and in vitro.Moreover,the large amounts of ROS produced by NOX2 further exacerbated insulin resistance and increased lipolysis in perirenal white adipose tissue(periWAT),thereby providing fatty acids for hepatic lipid synthesis.In addition,the interaction between AMPKα1 and p47phox was the pathway that mediated the high expression of NOX2 induced by a HCD.Our study systematically demonstrated the effect of a HCD on NAFLD.Elevated fatty acid influx is a unique molecular regulatory pathway that mediates HCD-induced NAFLD exacerbation,which is different from the effect of simple sugars.Additionally,NOX2 was suggested to be a specific and effective drug target for NAFLD.
基金Authors are grateful to the Hebei Agricultural University of China for the financial support of this work(3118094).
文摘Mushrooms contain multiple bioactive compounds of which dietary fibre is a representative type.Fortification of extracted or naturally derived dietary fibre in staple starchy foods constitutes a strategy to increase fibre intake in terms of cardiovascular disease and other metabolic diseases.Food matrix is viewed as a physical domain containing nutrients in which interactions and behaviours are different from those in isolation or free state.The nutritional effect of mushrooms'addition in the starchy food matrix is reviewed together with the alterations of cooking properties.Prospective studies include nutrients bioaccessibility due to the interfere of dietary fibres in consideration of their types and quality.The future approach to shaping microbial colonisation in the digestive tract through metabolites such as short-chain fatty acids from dietary fibres is required to sustain host physiology and health.
基金supported by the National Key R&D Program of China (2024YFF1000600)the National Natural Science Foundation of China (31821005,32261143466)+3 种基金the Hubei Fund to Support High Quality Development of Seed Industry (HBZY2023B001-08)the Science and Technology Major Program of Hubei Province (2021ABA011)the Hubei Provincial Natural Science Foundation of China (2023AFA043)the Earmarked Fund for China Agriculture Research System (CARS-01)。
文摘Dear Editor,Traditionally,the consumption of milled rice(starchy endosperm) as a staple food mainly provides calories for human society,and the lack of many important nutrients in such processed grains has led to malnutrition in rice-consuming regions worldwide(United Nations System Standing Committee on Nutrition,2004).
基金supported by the National Key Research and Development Program(2021YFD1200705)the Collaborative Innovation Center of the Beijing Academy of Agricultural and Forestry Sciences(KJCX20240406)the Science and Technology Innovation Special Construction Funded Program of the Beijing Academy of Agriculture and Forestry Sciences(KJCX20220401).
文摘Identifying and segmenting the vitreous and starchy endosperm of maize kernels is essential for texture analysis.However,the complex internal structure of maize kernels presents several challenges.In CT(computed tomog-raphy)images,the pixel intensity differences between the vitreous and starchy endosperm regions in maize kernel CT images are not distinct,potentially leading to low segmentation accuracy or oversegmentation.Moreover,the blurred edges between the vitreous and starchy endosperm make segmentation difficult,often resulting in jagged segmentation outcomes.We propose a deep learning-based CT image analysis pipeline to examine the internal structure of maize seeds.First,CT images are acquired using a multislice CT scanner.To improve the efficiency of maize kernel CT imaging,a batch scanning method is used.Individual kernels are accurately segmented from batch-scanned CT images using the Canny algorithm.Second,we modify the conventional architecture for high-quality segmentation of the vitreous and starchy endosperm in maize kernels.The conventional U-Net is modified by integrating the CBAM(convolutional block attention module)mechanism in the encoder and the SE(squeeze-and-excitation attention)mechanism in the decoder,as well as by using the focal-Tversky loss function instead of the Dice loss,and the boundary smoothing term is weighted as an additional loss term,named CSFTU-Net.The experimental results show that the CSFTU-Net model significantly improves the ability of segmenting vitreous and starchy endosperm.Finally,a segmented mask-based method is proposed to extract phenotype parameters of maize kernel texture,including the volume of the kernel(V),volume of the vitreous endosperm(VV),volume of starchy endosperm(SV),and ratios over their respective total kernel volumes(W/V and SV/V).The proposed pipeline facilitates the nondestructive quantification of the internal structure of maize kernels,offering valuable insights for maize breeding and processing.
