为进一步研究成花素(FLOWERING LOCUS T,FT)基因对植物营养生长的影响,通过结合qRT-PCR和生理学实验的方式对FT过表达及突变体植株进行比对分析.研究发现,FT过表达植株与野生型相比,其根毛短且稀疏,且具有分叉型、膨大型、波浪型等极性...为进一步研究成花素(FLOWERING LOCUS T,FT)基因对植物营养生长的影响,通过结合qRT-PCR和生理学实验的方式对FT过表达及突变体植株进行比对分析.研究发现,FT过表达植株与野生型相比,其根毛短且稀疏,且具有分叉型、膨大型、波浪型等极性生长缺陷表型;相反,突变体ft-10的根毛相对长且密集,略优于野生型,无极性生长缺陷表型.通过实时定量PCR分析与根毛起始伸长过程相关基因KOAJK、SCN1、RHD2、LRL3、RSL4、RHD6的表达量,FT过表达植株显著低于野生型,而突变体ft-10略高于野生型.结果表明,FT基因在根毛起始伸长过程中起负调控作用,影响根毛的极性生长及数量分布.本研究增加了对FT基因在营养生长过程中功能的认识,同时也为深入研究根系发育的分子机理奠定了基础.展开更多
Although some indica rice varieties have already been transformed by Agrobacterium,there is still great demand of developing transformation system for economically important indica varieties.Here,a fast and efficient ...Although some indica rice varieties have already been transformed by Agrobacterium,there is still great demand of developing transformation system for economically important indica varieties.Here,a fast and efficient method of Agrobacterium-mediated transformation for indica rice was developed,and an NcGDH transgenic genic male-sterile(GMS)indica rice 628S was generated using this method.The regenerated transgenic plantlets can be obtained within three months,and the transformation efficiency achieved about 17%.NcGDH transgenic 628S exhibited an enhanced capacity of ammonium assimilation and more effective panicles under low nitrogen conditions.Moreover the hybrid rice lines generated by NcGDH transgenic 628S showed 8%-27%yield advantage than those by the non-transgenic 628S.Taken together,these results provide an efficient transfbnnation method for indica rice and an opportunity to improve nitrogen use efficiency(NUE)and the heterosis of hybrid rice.展开更多
The expression of FOAl （F-box overexpressed/oppressed ABA signaling） in different organs of Arabidopsis, and in response to ABA and NaCI, was analyzed. The expression level of FOAl is higher in the root and is lower...The expression of FOAl （F-box overexpressed/oppressed ABA signaling） in different organs of Arabidopsis, and in response to ABA and NaCI, was analyzed. The expression level of FOAl is higher in the root and is lower in the stem, and is induced rapidly by ABA and NaC1. The phenotypes of T-DNA insertion mutant foal and FOAl overexpression lines FOAloxl and FOAlox2 were analyzed. The foal mutant exhibited a lower germination rate, shorter root length, more stomatal opening, in- creased proline accumulation and hypersensitivity to ABA compared with the wild type. In contrast, the overexpression lines showed lower sensitivity to ABA than the wild type. The expression levels of several ABA and stress-responsive transcription factors and genes were altered in the foal mutant in response to ABA. Compared with the wild type, the expression levels of ABA-responsive transcription factors were higher, but ABA and stress-responsive genes were lower in foal mutant. This study demonstrates that FOAl is an ABA signaling-related gene, and may play a negative role in ABA signaling.展开更多
Modified magnetic starch nanoparticles (FA-StNP@Fe2O3) were synthesized by conjugating folic acid (FA-PEG-NH2) onto the surface of magnetic starch nanoparticles (StNP@Fe2O3) prepared by reverse microemulsion method. T...Modified magnetic starch nanoparticles (FA-StNP@Fe2O3) were synthesized by conjugating folic acid (FA-PEG-NH2) onto the surface of magnetic starch nanoparticles (StNP@Fe2O3) prepared by reverse microemulsion method. The synthesized FA-StNP@Fe2O3 was investigated by transmission electron microscopy and zeta potential analysis. The average size of its well dispersed particles was 250 nm. The iron concentration of 2 mg/g was detected by phenanthroline method. Placing FA-StNP@Fe2O3 nanoparticles in the alternating magnetic field for 30 min resulted in an increase in the suspension temperature from ambient temperature (37℃) to a value between 42℃ and 43℃. Co-cultured nanoparticles and Hela cell line or normal HUEC-12 cell line, and the biological effects at the cellular level were investigated in the alternating magnetic field using MTT assay, Hochest-PI double staining and flow cytometry analysis. Experimental results showed that FA-StNP@Fe2O3 within acertain concentration range has no obvious effect on cell proliferation. When treated in the magnetic field, apoptosis rate on Hela induced by FA-StNP@Fe2O3 was 13.4%. Prussian blue staining analysis confirmed that the nanoparticles modified with folic acid had improved ability in tumor cell-targeting, and therefore, potential applications in biomedical and magnetocaloric areas. It is expected be applied in tumor targeting therapy in the near future.展开更多
Sustaining the release of therapeutic nanoparticles in a cell-, tissue-, or disease-specific manner is a potentially powerful technology. A new drug carrier-dialdehyde starch nanoparticle (DASNP) that can sustain the ...Sustaining the release of therapeutic nanoparticles in a cell-, tissue-, or disease-specific manner is a potentially powerful technology. A new drug carrier-dialdehyde starch nanoparticle (DASNP) that can sustain the loading and release of 5-fluorouracil (5-Fu) antitumor drug is reported in this study. IR spectrophotometer and 1H NMR confirmed the formation of aldehyde groups, and scan electron microscope determinations showed that the dialdehyde starch nanoparticles obtained had an average diameter of 90 nm. 5-Fu, the model drug, was conjugated into nanoparticles by aldehyde groups. These 5-Fu-binding nanoparticles significantly enhanced breast cancer cell (MCF-7) inhibition in vitro compared with free 5-Fu. After subcutaneous 0 injection in the breast tumor-loaded rats, 5-Fu-DASNP exhibited remarkable tumor-inhibitory efficacy determined by measuring tumor weight in vivo. The tumor inhibition of 5-Fu-DASNP was 61%±6%, whereas that of free 5-Fu was only 42%±4%. Bcl-2/Bax immunohistochem-istry studies indicated that 5-Fu-DASNP remarkably induced tumor tissue necrosis. These results demonstrated that the DASNP prepared in this work is a potentially effective drug carrier.展开更多
Phytochromes are a family of plant photoreceptors that mediate physiological and developmental re- sponses to red and far-red light. According to the affymetrix ATH1 microarray, phytochrome A (phyA) and phytochrome B ...Phytochromes are a family of plant photoreceptors that mediate physiological and developmental re- sponses to red and far-red light. According to the affymetrix ATH1 microarray, phytochrome A (phyA) and phytochrome B (phyB) together play a key role in transducing the Rc signals to light-responsive genes. In order to select those red light-responsive genes associated with phyA or phyB, a proteomic approach based on two-dimensional gel electrophoresis (2-DE) was used to compare the protein ex- pression patterns of the phyAphyB double mutant and the wild type of Arabidopsis thaliana (col-4) which grew under constant red light conditions for 7 d. Thirty-two protein spots which exhibited dif- ferences in protein abundance were identified by matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. The expression of ten genes corresponding to ten protein spots was analyzed by a semiquantitative reverse transcription-polymerase chain reaction. Two of the ten genes were confirmed by quantitative PCR (Q-PCR). The results showed that phytochromes may exert their function by regulating mRNA or protein expressions. Proteomic analysis may provide a novel pathway for identifying phytochrome-dependent genes.展开更多
文摘为进一步研究成花素(FLOWERING LOCUS T,FT)基因对植物营养生长的影响,通过结合qRT-PCR和生理学实验的方式对FT过表达及突变体植株进行比对分析.研究发现,FT过表达植株与野生型相比,其根毛短且稀疏,且具有分叉型、膨大型、波浪型等极性生长缺陷表型;相反,突变体ft-10的根毛相对长且密集,略优于野生型,无极性生长缺陷表型.通过实时定量PCR分析与根毛起始伸长过程相关基因KOAJK、SCN1、RHD2、LRL3、RSL4、RHD6的表达量,FT过表达植株显著低于野生型,而突变体ft-10略高于野生型.结果表明,FT基因在根毛起始伸长过程中起负调控作用,影响根毛的极性生长及数量分布.本研究增加了对FT基因在营养生长过程中功能的认识,同时也为深入研究根系发育的分子机理奠定了基础.
基金supported by the National Science Foundation of China(Grant Nos.31571635 and 31871595)Hunan Provincial Important Science and Technology Specific Projects(Grant No.2018NK1010)+2 种基金Natural Science Foundation of Hunan Province,China(Grant No.2020JJ4004)Public Subject of State Key Laboratory of Hybrid Rice(Hunan Hybrid Rice Research Center)(Grant No.2019KF02)China Postdoctoral Science Foundation(Grant No.2020M682561).
文摘Although some indica rice varieties have already been transformed by Agrobacterium,there is still great demand of developing transformation system for economically important indica varieties.Here,a fast and efficient method of Agrobacterium-mediated transformation for indica rice was developed,and an NcGDH transgenic genic male-sterile(GMS)indica rice 628S was generated using this method.The regenerated transgenic plantlets can be obtained within three months,and the transformation efficiency achieved about 17%.NcGDH transgenic 628S exhibited an enhanced capacity of ammonium assimilation and more effective panicles under low nitrogen conditions.Moreover the hybrid rice lines generated by NcGDH transgenic 628S showed 8%-27%yield advantage than those by the non-transgenic 628S.Taken together,these results provide an efficient transfbnnation method for indica rice and an opportunity to improve nitrogen use efficiency(NUE)and the heterosis of hybrid rice.
基金supported by the National Natural Science Foundation of China(Grant No.31171176)Research Fund for the Doctoral Program of Higher Education of China(Grant No.755228001)+1 种基金Natural Science Foundation of Hunan Province(Grant No.11JJA002)the National Key Laboratory of Plant Molecular Genetics(Grant No.Y109Z711T1)
文摘The expression of FOAl （F-box overexpressed/oppressed ABA signaling） in different organs of Arabidopsis, and in response to ABA and NaCI, was analyzed. The expression level of FOAl is higher in the root and is lower in the stem, and is induced rapidly by ABA and NaC1. The phenotypes of T-DNA insertion mutant foal and FOAl overexpression lines FOAloxl and FOAlox2 were analyzed. The foal mutant exhibited a lower germination rate, shorter root length, more stomatal opening, in- creased proline accumulation and hypersensitivity to ABA compared with the wild type. In contrast, the overexpression lines showed lower sensitivity to ABA than the wild type. The expression levels of several ABA and stress-responsive transcription factors and genes were altered in the foal mutant in response to ABA. Compared with the wild type, the expression levels of ABA-responsive transcription factors were higher, but ABA and stress-responsive genes were lower in foal mutant. This study demonstrates that FOAl is an ABA signaling-related gene, and may play a negative role in ABA signaling.
基金Supported by the Key Program for Science and Technology of Hunan Province (Grant No. 03NKY1001) Key Construction Program of the National "985" Project
文摘Modified magnetic starch nanoparticles (FA-StNP@Fe2O3) were synthesized by conjugating folic acid (FA-PEG-NH2) onto the surface of magnetic starch nanoparticles (StNP@Fe2O3) prepared by reverse microemulsion method. The synthesized FA-StNP@Fe2O3 was investigated by transmission electron microscopy and zeta potential analysis. The average size of its well dispersed particles was 250 nm. The iron concentration of 2 mg/g was detected by phenanthroline method. Placing FA-StNP@Fe2O3 nanoparticles in the alternating magnetic field for 30 min resulted in an increase in the suspension temperature from ambient temperature (37℃) to a value between 42℃ and 43℃. Co-cultured nanoparticles and Hela cell line or normal HUEC-12 cell line, and the biological effects at the cellular level were investigated in the alternating magnetic field using MTT assay, Hochest-PI double staining and flow cytometry analysis. Experimental results showed that FA-StNP@Fe2O3 within acertain concentration range has no obvious effect on cell proliferation. When treated in the magnetic field, apoptosis rate on Hela induced by FA-StNP@Fe2O3 was 13.4%. Prussian blue staining analysis confirmed that the nanoparticles modified with folic acid had improved ability in tumor cell-targeting, and therefore, potential applications in biomedical and magnetocaloric areas. It is expected be applied in tumor targeting therapy in the near future.
基金supported by the National Natural Science Foundation of China (31100433)
文摘Sustaining the release of therapeutic nanoparticles in a cell-, tissue-, or disease-specific manner is a potentially powerful technology. A new drug carrier-dialdehyde starch nanoparticle (DASNP) that can sustain the loading and release of 5-fluorouracil (5-Fu) antitumor drug is reported in this study. IR spectrophotometer and 1H NMR confirmed the formation of aldehyde groups, and scan electron microscope determinations showed that the dialdehyde starch nanoparticles obtained had an average diameter of 90 nm. 5-Fu, the model drug, was conjugated into nanoparticles by aldehyde groups. These 5-Fu-binding nanoparticles significantly enhanced breast cancer cell (MCF-7) inhibition in vitro compared with free 5-Fu. After subcutaneous 0 injection in the breast tumor-loaded rats, 5-Fu-DASNP exhibited remarkable tumor-inhibitory efficacy determined by measuring tumor weight in vivo. The tumor inhibition of 5-Fu-DASNP was 61%±6%, whereas that of free 5-Fu was only 42%±4%. Bcl-2/Bax immunohistochem-istry studies indicated that 5-Fu-DASNP remarkably induced tumor tissue necrosis. These results demonstrated that the DASNP prepared in this work is a potentially effective drug carrier.
基金Supported by the Grants from the "985" Program of China (Grant No. 200501)Hunan Province Science Technology Program Fund (Grant No. 06FJ315208FJ4211)+1 种基金Scientific Research Fund of the Hunan Provincial Education Department (Grant No.08B049)National Natural Science Foundation of China (Grant Nos. 30600368, 30770200 and 30871325).
文摘Phytochromes are a family of plant photoreceptors that mediate physiological and developmental re- sponses to red and far-red light. According to the affymetrix ATH1 microarray, phytochrome A (phyA) and phytochrome B (phyB) together play a key role in transducing the Rc signals to light-responsive genes. In order to select those red light-responsive genes associated with phyA or phyB, a proteomic approach based on two-dimensional gel electrophoresis (2-DE) was used to compare the protein ex- pression patterns of the phyAphyB double mutant and the wild type of Arabidopsis thaliana (col-4) which grew under constant red light conditions for 7 d. Thirty-two protein spots which exhibited dif- ferences in protein abundance were identified by matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. The expression of ten genes corresponding to ten protein spots was analyzed by a semiquantitative reverse transcription-polymerase chain reaction. Two of the ten genes were confirmed by quantitative PCR (Q-PCR). The results showed that phytochromes may exert their function by regulating mRNA or protein expressions. Proteomic analysis may provide a novel pathway for identifying phytochrome-dependent genes.
