The progressive destruction of condylar cartilage is a hallmark of the temporomandibular joint(TMJ) osteoarthritis(OA);however, its mechanism is incompletely understood. Here, we show that Kindlin-2, a key focal adhes...The progressive destruction of condylar cartilage is a hallmark of the temporomandibular joint(TMJ) osteoarthritis(OA);however, its mechanism is incompletely understood. Here, we show that Kindlin-2, a key focal adhesion protein, is strongly detected in cells of mandibular condylar cartilage in mice. We find that genetic ablation of Kindlin-2 in aggrecan-expressing condylar chondrocytes induces multiple spontaneous osteoarthritic lesions, including progressive cartilage loss and deformation, surface fissures, and ectopic cartilage and bone formation in TMJ. Kindlin-2 loss significantly downregulates the expression of aggrecan, Col2a1 and Proteoglycan 4(Prg4), all anabolic extracellular matrix proteins, and promotes catabolic metabolism in TMJ cartilage by inducing expression of Runx2and Mmp13 in condylar chondrocytes. Kindlin-2 loss decreases TMJ chondrocyte proliferation in condylar cartilages. Furthermore,Kindlin-2 loss promotes the release of cytochrome c as well as caspase 3 activation, and accelerates chondrocyte apoptosis in vitro and TMJ. Collectively, these findings reveal a crucial role of Kindlin-2 in condylar chondrocytes to maintain TMJ homeostasis.展开更多
Osteoarthritis(OA)is a chronic degenerative joint disorder that leads to disability and affects more than 500 million population worldwide.OA was believed to be caused by the wearing and tearing of articular cartilage...Osteoarthritis(OA)is a chronic degenerative joint disorder that leads to disability and affects more than 500 million population worldwide.OA was believed to be caused by the wearing and tearing of articular cartilage,but it is now more commonly referred to as a chronic whole-joint disorder that is initiated with biochemical and cellular alterations in the synovial joint tissues,which leads to the histological and structural changes of the joint and ends up with the whole tissue dysfunction.Currently,there is no cure for OA,partly due to a lack of comprehensive understanding of the pathological mechanism of the initiation and progression of the disease.Therefore,a better understanding of pathological signaling pathways and key molecules involved in OA pathogenesis is crucial for therapeutic target design and drug development.In this review,we first summarize the epidemiology of OA,including its prevalence,incidence and burdens,and OA risk factors.We then focus on the roles and regulation of the pathological signaling pathways,such as Wnt/β-catenin,NF-κB,focal adhesion,HIFs,TGFβ/ΒΜP and FGF signaling pathways,and key regulators AMPK,mTOR,and RUNX2 in the onset and development of OA.In addition,the roles of factors associated with OA,including MMPs,ADAMTS/ADAMs,and PRG4,are discussed in detail.Finally,we provide updates on the current clinical therapies and clinical trials of biological treatments and drugs for OA.Research advances in basic knowledge of articular cartilage biology and OA pathogenesis will have a significant impact and translational value in developing OA therapeutic strategies.展开更多
Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many pla...Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes.Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture.However,whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive.Here,we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene,HIGH TILLERING AND DWARF 1/DWARF17(HTD1/D17),which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7(CCD7),increases tiller number and improves grain yield in rice.We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1(SD1),both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s.Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.展开更多
Drought stress is a major environmental factor that limits the growth, development, and yield of rice(Oryza sativa L.). Histone deacetylases(HDACs) are involved in the regulation of drought stress responses. HDA704 is...Drought stress is a major environmental factor that limits the growth, development, and yield of rice(Oryza sativa L.). Histone deacetylases(HDACs) are involved in the regulation of drought stress responses. HDA704 is an RPD3/HDA1 class HDAC that mediates the deacetylation of H4K8(lysine 8of histone H4) for drought tolerance in rice. In this study, we show that plants overexpressing HDA704(HDA704-OE) are resistant to drought stress and sensitive to abscisic acid(ABA), whereas HDA704 knockout mutant(hda704) plants displayed decreased drought tolerance and ABA sensitivity.Transcriptome analysis revealed that HDA704 regulates the expression of ABA-related genes in response to drought stress. Moreover, HDA704 was recruited by a drought-resistant transcription factor,WAX SYNTHESIS REGULATORY 2(Os WR2), and co-regulated the expression of the ABA biosynthesis genes NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3(NCED3), NCED4, and NCED5 under drought stress. HDA704 also repressed the expression of ABA-INSENSITIVE 5(Os ABI5) and DWARF AND SMALL SEED 1(Os DSS1) by regulating H4K8ac levels in the promoter regions in response to polyethylene glycol 6000 treatment. In agreement, the loss of Os ABI5 function increased resistance to dehydration stress in rice. Our results demonstrate that HDA704 is a positive regulator of the drought stress response and offers avenues for improving drought resistance in rice.展开更多
Accurate crop detection is the prerequisite for the operation of intelligent agricultural machinery.Image recognition usually lacks accurate orientation information,and Lidar point clouds are not easy to distinguish d...Accurate crop detection is the prerequisite for the operation of intelligent agricultural machinery.Image recognition usually lacks accurate orientation information,and Lidar point clouds are not easy to distinguish different objects.Fortunately,the fusion of images and Lidar points can complement each other.This research aimed to detect maize(Zea mays L.)seedlings by fusing Lidar data with images.By applying coordinate transformation and time stamps,the images and Lidar points were realized homogeneous in spatial as well as temporal dimensions.Deep learning was used to develop a maize seedling recognition model,then the model recognized maize seedlings by labeling them with bounding boxes.Meanwhile,Lidar points were mapped to the bounding boxes.Only one-third of points that fell into the right middle of bounding boxes were selected for clustering operation,the calculated center of the cluster provided spatial information for target maize seedlings.This study modified the classical single shot multi-box detector(SSD)by merely linking the last feature map to the final output layer,owing to the higher feature maps having the unique advantages of detecting relatively larger objects.In images,maize seedlings were just the largest objects owing to be shot on purpose.This modification enabled the recognition model to finish recognizing an image by only consuming around 60 ms,which saved about 10 ms/image compared with the classical SSD model.The experiment was conducted in a maize field,and the maize was during the elongation stage.Experimental results demonstrated that the standard deviations for maximum distance error and maximum angle error were 1.4 cm and 1.1°,respectively,which can be tolerated under current technical requirements.Since agricultural fields are subject to staple crop-orientated and changeable ambient environment,the fusion of images and Lidar points can derive more precision information,and make agricultural machinery smarter.This study can act as an upstream technology for other researches on intelligent agricultural machinery.展开更多
Self-propelled maize harvesters are prone to overturning when operating on sloping ground.Solving this problem presents a major technical challenge for researchers.Existing undercarriage leveling technologies are most...Self-propelled maize harvesters are prone to overturning when operating on sloping ground.Solving this problem presents a major technical challenge for researchers.Existing undercarriage leveling technologies are mostly single leveling mechanisms and have a small adjustable angle.A chassis attitude adjustment device has been developed to increase the flexibility of the harvester to slope terrain.The device is made up of a double leveling mechanism and a leveling control system,and it is used to regulate the lateral and longitudinal attitude of the harvester while it is operating.To maintain the attitude of the fuselage within the desired range,the leveling control system regulates the amount of hydraulic cylinder expansion and contraction.The kinematic analysis of the leveling mechanism was done using the vector approach,and the device can be adjusted for lateral and longitudinal inclination between-10°and 17°,and-43.1°and 43.1°,respectively.According to the findings of the static tests,the chassis attitude adjustment device can level the fuselage in four tilt attitudes-10°uphill,17°downhill,25°sideways slope forward,and 25°sideways slope return-with a maximum leveling error of 0.37°and the fastest leveling rate of 0.233 s/(°).For the purpose of evaluating the chassis attitude adjustment performance in the field tests,the tilt inclination of the fuselage was selected as an assessment indicator.The body tilt of the harvester ranged from 0.13°to 1.81°at a harvester speed of 2.5 km/h,with an average body tilt angle of 0.78°,showing that the undercarriage attitude adjustment system was capable of actively leveling the maize harvester attitude.This study enabled the dynamic equilibrium for the maize harvester,which can act as an upstream technology for the design of slope travel devices.展开更多
基金supported, in part, by the National Key Research and Development Program of China Grants (2019YFA0906004)the National Natural Science Foundation of China Grants (81991513, 81870532, 82172375)+1 种基金the Guangdong Provincial Science and Technology Innovation Council Grant (2017B030301018)the Shenzhen Municipal Science and Technology Innovation Council Grant (20200925150409001)。
文摘The progressive destruction of condylar cartilage is a hallmark of the temporomandibular joint(TMJ) osteoarthritis(OA);however, its mechanism is incompletely understood. Here, we show that Kindlin-2, a key focal adhesion protein, is strongly detected in cells of mandibular condylar cartilage in mice. We find that genetic ablation of Kindlin-2 in aggrecan-expressing condylar chondrocytes induces multiple spontaneous osteoarthritic lesions, including progressive cartilage loss and deformation, surface fissures, and ectopic cartilage and bone formation in TMJ. Kindlin-2 loss significantly downregulates the expression of aggrecan, Col2a1 and Proteoglycan 4(Prg4), all anabolic extracellular matrix proteins, and promotes catabolic metabolism in TMJ cartilage by inducing expression of Runx2and Mmp13 in condylar chondrocytes. Kindlin-2 loss decreases TMJ chondrocyte proliferation in condylar cartilages. Furthermore,Kindlin-2 loss promotes the release of cytochrome c as well as caspase 3 activation, and accelerates chondrocyte apoptosis in vitro and TMJ. Collectively, these findings reveal a crucial role of Kindlin-2 in condylar chondrocytes to maintain TMJ homeostasis.
基金We apologize to the authors whose relevant studies have not been included in this review article. This work was supported, in part, by the National Key Research and Development Program of China Grants (2019YFA0906004)the National Natural Science Foundation of China Grants (82230081, 82250710175, 82172375, 81991513, and 82261160395)+3 种基金the Shenzhen Stable Support Plan Program for Higher Education Institutions (20200925150409001)the Shenzhen Fundamental Research Program (JCYJ20220818100617036)the Shenzhen Key Laboratory of Cell Microenvironment Grant (ZDSYS20140509142721429)the Guangdong Provincial Science and Technology Innovation Council Grant (2017B030301018).
文摘Osteoarthritis(OA)is a chronic degenerative joint disorder that leads to disability and affects more than 500 million population worldwide.OA was believed to be caused by the wearing and tearing of articular cartilage,but it is now more commonly referred to as a chronic whole-joint disorder that is initiated with biochemical and cellular alterations in the synovial joint tissues,which leads to the histological and structural changes of the joint and ends up with the whole tissue dysfunction.Currently,there is no cure for OA,partly due to a lack of comprehensive understanding of the pathological mechanism of the initiation and progression of the disease.Therefore,a better understanding of pathological signaling pathways and key molecules involved in OA pathogenesis is crucial for therapeutic target design and drug development.In this review,we first summarize the epidemiology of OA,including its prevalence,incidence and burdens,and OA risk factors.We then focus on the roles and regulation of the pathological signaling pathways,such as Wnt/β-catenin,NF-κB,focal adhesion,HIFs,TGFβ/ΒΜP and FGF signaling pathways,and key regulators AMPK,mTOR,and RUNX2 in the onset and development of OA.In addition,the roles of factors associated with OA,including MMPs,ADAMTS/ADAMs,and PRG4,are discussed in detail.Finally,we provide updates on the current clinical therapies and clinical trials of biological treatments and drugs for OA.Research advances in basic knowledge of articular cartilage biology and OA pathogenesis will have a significant impact and translational value in developing OA therapeutic strategies.
基金This work was supported by the National Key Research and Development Program of China(grant no.2016YFpO101801)National Natural Science Foundation of China(grant nos.91735304,31971921,31601285)+1 种基金Natural Science Foundation of Zhejiang Province(grant no.LR20C130001)Shenzhen Peacock Plan(grant no.KQTD2016113010482651)。
文摘Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes.Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture.However,whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive.Here,we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene,HIGH TILLERING AND DWARF 1/DWARF17(HTD1/D17),which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7(CCD7),increases tiller number and improves grain yield in rice.We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1(SD1),both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s.Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.
基金supported by the Nature Science Foundation of China (31961143015 To G.X.)Hainan Yazhou Bay Laboratory (B21HJ0215 To J.H)。
文摘Drought stress is a major environmental factor that limits the growth, development, and yield of rice(Oryza sativa L.). Histone deacetylases(HDACs) are involved in the regulation of drought stress responses. HDA704 is an RPD3/HDA1 class HDAC that mediates the deacetylation of H4K8(lysine 8of histone H4) for drought tolerance in rice. In this study, we show that plants overexpressing HDA704(HDA704-OE) are resistant to drought stress and sensitive to abscisic acid(ABA), whereas HDA704 knockout mutant(hda704) plants displayed decreased drought tolerance and ABA sensitivity.Transcriptome analysis revealed that HDA704 regulates the expression of ABA-related genes in response to drought stress. Moreover, HDA704 was recruited by a drought-resistant transcription factor,WAX SYNTHESIS REGULATORY 2(Os WR2), and co-regulated the expression of the ABA biosynthesis genes NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3(NCED3), NCED4, and NCED5 under drought stress. HDA704 also repressed the expression of ABA-INSENSITIVE 5(Os ABI5) and DWARF AND SMALL SEED 1(Os DSS1) by regulating H4K8ac levels in the promoter regions in response to polyethylene glycol 6000 treatment. In agreement, the loss of Os ABI5 function increased resistance to dehydration stress in rice. Our results demonstrate that HDA704 is a positive regulator of the drought stress response and offers avenues for improving drought resistance in rice.
基金financially supported by the National Natural Science Foundation of China(Grant No.31901408)the Science and Technology Development Plan of Jilin Province(Grant No.20200201206JC).
文摘Accurate crop detection is the prerequisite for the operation of intelligent agricultural machinery.Image recognition usually lacks accurate orientation information,and Lidar point clouds are not easy to distinguish different objects.Fortunately,the fusion of images and Lidar points can complement each other.This research aimed to detect maize(Zea mays L.)seedlings by fusing Lidar data with images.By applying coordinate transformation and time stamps,the images and Lidar points were realized homogeneous in spatial as well as temporal dimensions.Deep learning was used to develop a maize seedling recognition model,then the model recognized maize seedlings by labeling them with bounding boxes.Meanwhile,Lidar points were mapped to the bounding boxes.Only one-third of points that fell into the right middle of bounding boxes were selected for clustering operation,the calculated center of the cluster provided spatial information for target maize seedlings.This study modified the classical single shot multi-box detector(SSD)by merely linking the last feature map to the final output layer,owing to the higher feature maps having the unique advantages of detecting relatively larger objects.In images,maize seedlings were just the largest objects owing to be shot on purpose.This modification enabled the recognition model to finish recognizing an image by only consuming around 60 ms,which saved about 10 ms/image compared with the classical SSD model.The experiment was conducted in a maize field,and the maize was during the elongation stage.Experimental results demonstrated that the standard deviations for maximum distance error and maximum angle error were 1.4 cm and 1.1°,respectively,which can be tolerated under current technical requirements.Since agricultural fields are subject to staple crop-orientated and changeable ambient environment,the fusion of images and Lidar points can derive more precision information,and make agricultural machinery smarter.This study can act as an upstream technology for other researches on intelligent agricultural machinery.
基金financially supported by the National Key R&D Program of China(Grant No.2022YFD1500701)the Jilin Science and Technology Development Plan(Grant Nos.20210202019NC,20220203081SF).
文摘Self-propelled maize harvesters are prone to overturning when operating on sloping ground.Solving this problem presents a major technical challenge for researchers.Existing undercarriage leveling technologies are mostly single leveling mechanisms and have a small adjustable angle.A chassis attitude adjustment device has been developed to increase the flexibility of the harvester to slope terrain.The device is made up of a double leveling mechanism and a leveling control system,and it is used to regulate the lateral and longitudinal attitude of the harvester while it is operating.To maintain the attitude of the fuselage within the desired range,the leveling control system regulates the amount of hydraulic cylinder expansion and contraction.The kinematic analysis of the leveling mechanism was done using the vector approach,and the device can be adjusted for lateral and longitudinal inclination between-10°and 17°,and-43.1°and 43.1°,respectively.According to the findings of the static tests,the chassis attitude adjustment device can level the fuselage in four tilt attitudes-10°uphill,17°downhill,25°sideways slope forward,and 25°sideways slope return-with a maximum leveling error of 0.37°and the fastest leveling rate of 0.233 s/(°).For the purpose of evaluating the chassis attitude adjustment performance in the field tests,the tilt inclination of the fuselage was selected as an assessment indicator.The body tilt of the harvester ranged from 0.13°to 1.81°at a harvester speed of 2.5 km/h,with an average body tilt angle of 0.78°,showing that the undercarriage attitude adjustment system was capable of actively leveling the maize harvester attitude.This study enabled the dynamic equilibrium for the maize harvester,which can act as an upstream technology for the design of slope travel devices.
