Stress-induced expression of the sweetpotato gene <i>IbLEA14</i> in poplar confers enhanced tolerance to multiple abiotic stresses

Ke, Qingbo,Park, Sung-Chul,Ji, Chang Yoon,Kim, Ho Soo,Wang, Zhi,Wang, Shiwen,Li, Hongbing,Xu, Bingcheng,Deng, Xiping,Kwak, Sang-Soo Elsevier 2018 Environmental and experimental botany Vol.156 No.-

<P><B>Abstract</B></P> <P>Late embryogenesis abundant (LEA) proteins are small, highly hydrophilic proteins that act as protectors of macromolecules and increase abiotic stress tolerance in plants. We previously reported that overexpressing sweetpotato <I>IbLEA14</I> under the control of the <I>CaMV 35S</I> promoter increased osmotic and salt stress tolerance in transgenic sweetpotato calli. In this study, we generated transgenic poplar plants (<I>Populus alba × P. glandulosa</I>) expressing <I>IbLEA14</I> under the control of the oxidative stress-inducible <I>SWPA2</I> promoter (referred to as SL plants). Among the 15 SL plants obtained, three lines (SL2, SL7, and SL12) were established based on <I>IbLEA14</I> transcript levels, tolerance to salt stress and Southern blot analysis. The SL plants exhibited less damage in response to methyl viologen-mediated oxidative stress than non-transgenic (NT) plants. SL plants also showed enhanced tolerance to drought, salt, and heat stress, which was associated with higher photosystem II efficiency and lower malondialdehyde levels compared with NT plants. Furthermore, SL plants had higher levels of monolignol biosynthesis-related gene transcripts under drought stress compared with NT plants. Finally, SL plants exhibited increased tolerance to heat stress, which is associated with the high thermostability of IbLEA14 protein. SL plants might be useful for reforestation on global marginal lands, including desertification and reclaimed areas.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>IbLEA14</I> gene was transformed into poplar plants. </LI> <LI> Transgenic poplars exhibit increased tolerance to MV-mediated oxidative, drought, salt and heat stress. </LI> <LI> Overproduction of IbLEA14 affects lignification and thermostability of transgenic poplars. </LI> </UL> </P>

Overexpression of the potato StEPF2 gene confers enhanced drought tolerance in Arabidopsis

Yanli Wang,Tian Xie,Chunli Zhang,Juanjuan Li,Zhi Wang,Hongbing Li,Xiping Liu,Li-Na Yin,Shi-Wen Wang,Sui-Qi Zhang,Xiping Deng,Qingbo Ke 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.4

Epidermal patterning factor 2 (EPF2) is a negative regulator of stomatal development, and is essential for plant growth, development, and environmental stress responses. However, the role of EPF2 in potato (Solanum tuberosum) has not been investigated to date. Here, we cloned and characterized the potato EPF2-like gene (StEPF2). StEPF2 is predominantly intercellular space localized and its transcripts were rhythmically expressed, and showed the highest expression in apical unexpanded leaves. Expression of StEPF2 was markedly down-regulated in response to abscisic acid and sodium chloride treatments; however, upon the application of polyethylene glycol, the expression of StEPF2 peaked at 4 h and then decreased gradually. Overexpression of StEPF2 in Arabidopsis (OE) substantially reduced stomatal density and photosynthetic rate, but had little effects on plant growth. Under drought stress, OE lines maintained higher photosynthetic rates, photosystem II efficiency, and instantaneous water use efficiency than wild-type (WT) plants. Moreover, OE lines showed less water loss and hydrogen peroxide accumulation in detached leaves compared with WT plants. Thus, our results suggest that StEPF2 acts as a negative regulator of stomatal development in potato, indicating that the role of EPF2 is conserved across plant species. Overall, StEPF2 represents an important target for the development of drought-tolerant potato cultivars via genetic engineering.

Policy Iteration Algorithm Based Fault Tolerant Tracking Control: An Implementation on Reconfigurable Manipulators

Li, Yuanchun,Xia, Hongbing,Zhao, Bo The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.4

This paper proposes a novel fault tolerant tracking control (FTTC) scheme for a class of nonlinear systems with actuator failures based on the policy iteration (PI) algorithm and the adaptive fault observer. The estimated actuator failure from an adaptive fault observer is utilized to construct an improved performance index function that reflects the failure, regulation and control simultaneously. With the help of the proper performance index function, the FTTC problem can be transformed into an optimal control problem. The fault tolerant tracking controller is composed of the desired controller and the approximated optimal feedback one. The desired controller is developed to maintain the desired tracking performance at the steady-state, and the approximated optimal feedback controller is designed to stabilize the tracking error dynamics in an optimal manner. By establishing a critic neural network, the PI algorithm is utilized to solve the Hamilton-Jacobi-Bellman equation, and then the approximated optimal feedback controller can be derived. Based on Lyapunov technique, the uniform ultimate boundedness of the closed-loop system is proven. The proposed FTTC scheme is applied to reconfigurable manipulators with two degree of freedoms in order to test the effectiveness via numerical simulation.

Color Image Segmentation Algorithms based on Granular Computing Clustering

Hongbing Liu,Lei Li,Chang-an Wu 보안공학연구지원센터(IJSIP) 2014 International Journal of Signal Processing, Image Vol.7 No.1

Space-Time Quantization and Motion-Aligned Reconstruction for Block-Based Compressive Video Sensing

( Ran Li ),( Hongbing Liu ),( Wei He ),( Xingpo Ma ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.1

The Compressive Video Sensing (CVS) is a useful technology for wireless systems requiring simple encoders but handling more complex decoders, and its rate-distortion performance is highly affected by the quantization of measurements and reconstruction of video frame, which motivates us to presents the Space-Time Quantization (ST-Q) and Motion-Aligned Reconstruction (MA-R) in this paper to both improve the performance of CVS system. The ST-Q removes the space-time redundancy in the measurement vector to reduce the amount of bits required to encode the video frame, and it also guarantees a low quantization error due to the fact that the high frequency of small values close to zero in the predictive residuals limits the intensity of quantizing noise. The MA-R constructs the Multi-Hypothesis (MH) matrix by selecting the temporal neighbors along the motion trajectory of current to-be-reconstructed block to improve the accuracy of prediction, and besides it reduces the computational complexity of motion estimation by the extraction of static area and 3-D Recursive Search (3DRS). Extensive experiments validate that the significant improvements is achieved by ST-Q in the rate-distortion as compared with the existing quantization methods, and the MA-R improves both the objective and the subjective quality of the reconstructed video frame. Combined with ST-Q and MA-R, the CVS system obtains a significant rate-distortion performance gain when compared with the existing CS-based video codecs.

Policy Iteration Algorithm Based Fault Tolerant Tracking Control

Yuanchun Li,Hongbing Xia,Bo Zhao 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.4

This paper proposes a novel fault tolerant tracking control (FTTC) scheme for a class of nonlinear systems with actuator failures based on the policy iteration (PI) algorithm and the adaptive fault observer. The estimated actuator failure from an adaptive fault observer is utilized to construct an improved performance index function that reflects the failure, regulation and control simultaneously. With the help of the proper performance index function, the FTTC problem can be transformed into an optimal control problem. The fault tolerant tracking controller is composed of the desired controller and the approximated optimal feedback one. The desired controller is developed to maintain the desired tracking performance at the steady-state, and the approximated optimal feedback controller is designed to stabilize the tracking error dynamics in an optimal manner. By establishing a critic neural network, the PI algorithm is utilized to solve the Hamilton-Jacobi-Bellman equation, and then the approximated optimal feedback controller can be derived. Based on Lyapunov technique, the uniform ultimate boundedness of the closed-loop system is proven. The proposed FTTC scheme is applied to reconfigurable manipulators with two degree of freedoms in order to test the effectiveness via numerical simulation.

CO2-responsive Pickering emulsion stablized by modified silica nanoparticles: A dissipative particle dynamics simulation study

Yan Wang,Hongbing Wang,Chunling Li,Shuangqing Sun,Songqing Hu 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.97 No.-

Dissipative particle dynamics (DPD) simulations were applied to investigate the effect of SiO2nanoparticles (SNPs) modified with different tertiary amine chain length and concentration on O/Wemulsion properties, the influence mechanism was also revealed from the molecular level. On this basis,the influence of the modified SNPs volume fraction in the emulsion system was studied. The resultsshowed that with the increase number of tertiary amine chain alkyl carbon, the stability of the originalemulsion system wasfirst enhanced and then weakened while the responsiveness of the protonatedemulsion system wasfirst weakened and then slightly enhanced, the number of tertiary amine chainsmodified on SNPs has the same influence rule on emulsion performance, which was determined by thehydrophobicity of modified SNPs. In addition, with the increase of the modified SNPs volume fraction inthe emulsion system, the stability of the emulsion is gradually enhanced. However, when the volumefraction of SiO2 exceeds 3%, the amplitude of stability enhancement decreases. The increase in theinteraction energy between oil droplets in the equilibrium process is caused by emulsion fusion, which inturn is affected by SNPs. The repulsive force between oil and water is greater than that between two oildrops, which is the reason for the oil drop fusion. The presence of SNPs can reduce the repulsive forcebetween oil and water to different degrees, thus slowing down the fusion of emulsion.

Changes in plant anthocyanin levels in response to abiotic stresses: a meta-analysis

Yan Wenjie,Li Juanjuan,Lin Xinyue,Wang Lina,Yang Xiaoxiao,Xia Xiangyu,Zhang Yuxin,Yang Shaoyu,Li Hongbing,Deng Xiping,Ke Qingbo 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.5

Anthocyanins are small molecule antioxidants that play important roles in plant response and resistance to abiotic stresses. Their levels increase when plants are exposed to abiotic stress. However, the general response patterns and magnitude of anthocyanin increase, and how they confer resistance to abiotic stresses, are difficult to evaluate because of the influence of experimental variables. In this study, changes in plant anthocyanin content under different abiotic stresses and the effect of anthocyanin overproduction on various physiological indicators were investigated through meta-analysis derived from 1039 datasets of 102 studies. Results showed that among the different stress types, heavy metals, especially copper (Cu) and mercury (Hg), induced the most significant synthesis of anthocyanins. Among the different types of drought treatments, mannitol caused anthocyanin content in plants to increase by 2.4-fold, which was more significant than that of polyethylene glycol and natural drought. Furthermore, UV stress led plant anthocyanins to increase 1.3-fold in C4 plants, which was higher than that in C3 plants. In addition, anthocyanins increased the most when the applied stresses were low and moderate, and of short duration. Moreover, plants overexpressing genes encoding MYB transcription factors increased anthocyanin content by 5.8-fold and significantly improved plant stress tolerance. Among the 21 physiological indicators, glutathione and proline levels increased the most in transgenic plants overproducing anthocyanins when exposed to abiotic stress. Taken together, this meta-analysis indicates that anthocyanins enhance stress tolerance by improving the antioxidant, metal-chelating, and osmoregulatory abilities of the plant. The results presented here can help guide future applications of anthocyanins as plant growth regulators in dryland agriculture and breeding for plant stress tolerance.

A Novel Passivity-Based Resonant Instability Suppression Method for Grid-Connected VSC

Jiancheng Zhao,Kai Li,Xiaodong Wang,Chuan Xie,Hongbing Xu 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.1

The interaction between the three-phase voltage source converters (VSCs) and the power grid may cause high-frequency resonant instable problems. Studies have indicated that the non-passivity of VSCs is the main reason that leads to the resonances. The above-mentioned passive means that the equivalent output admittance of the VSC has a positive real part. In this paper, a novel damped Smith predictor is proposed to suppress the resonant instability problem that caused by time delay. The research proved that the proposed Smith predictor can signifi cantly improve the passivity of the VSC by reducing the width of the negative real part at the high-frequencies. Simulation and experimental results demonstrate that the proposed Smith predictor can distinctly improve the robustness of the VSC.

Tunable stability of oil-containing foam systems with different concentrations of SDS and hydrophobic silica nanoparticles

Shuangqing Sun,Yan Wang,Congtai Yuan,Hongbing Wang,Wendong Wang,Jianhui Luo,Chunling Li,Songqing Hu 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.82 No.-

Experiment and molecular dynamics simulation were carried out to study the tunable stability of oilcontainingSDS-stabilized Nitrogen-in-water foam. The experimental results show that the foam stabilitycould be tuned by the concentrations of SDS and modified SiO2 nanoparticles. In the foam systems with alow SDS concentration (0.2 wt.%), the foams show poor stability and the foam stability was almost notaffected by the addition of modified SiO2 nanoparticles. The foam stability was greatly improved atmoderate SDS concentration (0.5 wt.%), it enhancedfirst and then weakened with the increase ofmodified SiO2 concentration, and the half-life time achieved a maximum value of 1292 s at 0.05 wt.%modified SiO2. However, at high SDS concentration (0.8 wt.%), the foam stability was pretty good exceptfor when the modified SiO2 concentration is too high (>0.2 wt.%). The microscopic mechanism wasobtained by investigating the structural and dynamic properties of the foamfilm. The simulation workshowed consistent results of foam stability with the experimental results. Moreover, it also revealed thatthe concentration and configuration of SDS will affect its interaction with SiO2 and oil molecule, which iscritical to foam stability.