Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification...Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification in modern plant biotechnology.However,the investigation of gene silencing and editing in radish remains limited.In this study,a bleaching phenotype was generated through the knockdown of RsPDS using tobacco rattle virus(TRV)-and turnip yellow mosaic virus(TYMV)-mediated gene silencing vectors.The TYMV-mediated gene silencing efficiency was higher than the TRV-based VIGS system in radish.The expression level of RsPDS was significantly inhibited using VIGS in'NAU-067'radish leaves.The rootless seedlings of‘NAU-067'were infected with Agrobacterium rhizogenes using the 2300GN-Ubi-RsPDS-Cas9 vector with two target sequences.Nine adventitious roots were blue with GUs staining,and four of these adventitious roots were edited at target sequence 1 of the RsPDS gene as indicated by Sanger sequencing.Furthermore,albino lines were generated with A.tumefaciens-mediated transformation of radish cotyledons.Five base substitutions and three base deletions occurred at target sequence 2 in Line 1,and three base insertions and three base substitutions occurred at target sequence 1 in Line 2.This study shows that VIGS and CRISPR/Cas9 techniques can be employed to precisely verify the biological functions of genes in radish,which will facilitate the genetic improvement of vital horticultural traits in radish breeding programs.展开更多
Theoretical simulations about manipulating vector solitons with super-sech pulse shapes are conducted based on an optical fiber system.By changing the temporal pulses’parameters when the orthogonally polarized pulses...Theoretical simulations about manipulating vector solitons with super-sech pulse shapes are conducted based on an optical fiber system.By changing the temporal pulses’parameters when the orthogonally polarized pulses have the same or different input central wavelengths,the output modes in orthogonal directions will demonstrate different properties.When the input orthogonal modes have the same central wavelength,the“2+2”pseudo-high-order vector soliton can be generated when the time delay is changed.While under the condition of different central wavelengths,orthogonal pulses with multiple peaks accompanied with two wavelengths can be achieved through varying the projection angle,time delay or phase difference.Our simulations are helpful to the study of optical soliton dynamics in optical fiber systems.展开更多
This paper investigates the impact of China's city size and urban population concentration on city productivity by developing a distinctive index based on global nighttime light data.Using the panel data of 280 pr...This paper investigates the impact of China's city size and urban population concentration on city productivity by developing a distinctive index based on global nighttime light data.Using the panel data of 280 prefecture cities from 2004 to 2013 and employing dynamic system generalized method of moments and panel threshold model regression techniques,our results show that city size has a positive impact on city productivity;therefore,cities in China still have the potential to expand.While moderate urban population concentration can benefit city productivity,excessively concentrated urban population distribution may impede the growth of city productivity.We also find that the level of labor income significantly affects the impacts of urban agglomeration on labor productivity.Therefore,our results imply that city development policies should focus more on how to appropriately allocate economic activities and adjust population distribution in urban areas according to different stages of economic development.展开更多
基金This work was supported by Jiangsu Seed Industry Revitalization Project,China[JBGS(2021)071]Fundamental Research Funds for the Central Universities,China(YDZX2023019)+3 种基金the National Natural Science Foundation of China(32172579)the earmarked fund for Jiangsu Agricultural Industry Technology System,China[JATS(2023)421]the Jiangsu Postgraduate Scientific Research Innovation Plan,China(KYCX21_0610-2021)the Project Founded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD).
文摘Virus-induced gene silencing(VIGS)and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)systems are effective technologies for rapid and accurate gene function verification in modern plant biotechnology.However,the investigation of gene silencing and editing in radish remains limited.In this study,a bleaching phenotype was generated through the knockdown of RsPDS using tobacco rattle virus(TRV)-and turnip yellow mosaic virus(TYMV)-mediated gene silencing vectors.The TYMV-mediated gene silencing efficiency was higher than the TRV-based VIGS system in radish.The expression level of RsPDS was significantly inhibited using VIGS in'NAU-067'radish leaves.The rootless seedlings of‘NAU-067'were infected with Agrobacterium rhizogenes using the 2300GN-Ubi-RsPDS-Cas9 vector with two target sequences.Nine adventitious roots were blue with GUs staining,and four of these adventitious roots were edited at target sequence 1 of the RsPDS gene as indicated by Sanger sequencing.Furthermore,albino lines were generated with A.tumefaciens-mediated transformation of radish cotyledons.Five base substitutions and three base deletions occurred at target sequence 2 in Line 1,and three base insertions and three base substitutions occurred at target sequence 1 in Line 2.This study shows that VIGS and CRISPR/Cas9 techniques can be employed to precisely verify the biological functions of genes in radish,which will facilitate the genetic improvement of vital horticultural traits in radish breeding programs.
基金Project supported by the National Key Research and Development Program of China(Grant No.2018YFB0504500)the National Natural Science Foundation of China(Grant Nos.62105208,51972317,and 61875052)+2 种基金Shanghai Sailing Program(Grant No.20YF1447500)Special Project for Industrialization of High-tech Science and Technology between Jilin Province and the Chinese Academy of Sciences(Grant No.2021SYHZ0029)Natural Science Foundation of Shanghai(Grant No.22ZR1470700)。
文摘Theoretical simulations about manipulating vector solitons with super-sech pulse shapes are conducted based on an optical fiber system.By changing the temporal pulses’parameters when the orthogonally polarized pulses have the same or different input central wavelengths,the output modes in orthogonal directions will demonstrate different properties.When the input orthogonal modes have the same central wavelength,the“2+2”pseudo-high-order vector soliton can be generated when the time delay is changed.While under the condition of different central wavelengths,orthogonal pulses with multiple peaks accompanied with two wavelengths can be achieved through varying the projection angle,time delay or phase difference.Our simulations are helpful to the study of optical soliton dynamics in optical fiber systems.
文摘This paper investigates the impact of China's city size and urban population concentration on city productivity by developing a distinctive index based on global nighttime light data.Using the panel data of 280 prefecture cities from 2004 to 2013 and employing dynamic system generalized method of moments and panel threshold model regression techniques,our results show that city size has a positive impact on city productivity;therefore,cities in China still have the potential to expand.While moderate urban population concentration can benefit city productivity,excessively concentrated urban population distribution may impede the growth of city productivity.We also find that the level of labor income significantly affects the impacts of urban agglomeration on labor productivity.Therefore,our results imply that city development policies should focus more on how to appropriately allocate economic activities and adjust population distribution in urban areas according to different stages of economic development.
