The tolerance of rice to drought and saline stress is crucial for maintaining yields and promoting widespread cultivation.From an ethyl methanesulfonate(EMS)-mutagenized mutant library,we identified a mutant that is s...The tolerance of rice to drought and saline stress is crucial for maintaining yields and promoting widespread cultivation.From an ethyl methanesulfonate(EMS)-mutagenized mutant library,we identified a mutant that is susceptible to osmotic stress,named Osmotic Stress Sensitivity 1(Oss1).Using MutMap sequencing,we characterized the role of a choline transporter-related family gene,CTR4(Choline Transporter-Related 4),in rice’s tolerance to drought and salt stress.CTR4 plays a critical role in regulating membrane lipid synthesis.In knockout mutants,the total membrane lipid content,especially unsaturated fatty acids,was significantly reduced.Compared with the wild type,knockout mutants exhibited decreased membrane lipid stability under drought and salt stress,faster water loss,higher relative electrolyte leakage,and lower levels of proline and soluble sugars,leading to impaired tolerance to drought and salt stress.In contrast,the overexpression of CTR4 enhanced seedling tolerance to drought and saline stress.The overexpression lines displayed lower malondialdehyde levels,reduced relative electrolyte leakage,and slower rates of leaf water loss under stress conditions,thereby improving seedling survival rates during stress.Moreover,lipid synthesis gene expression was down-regulated in CTR4 mutants,potentially exacerbating membrane permeability defects and further compromising stress resistance.These findings suggest that CTR4 mediates choline transport and influences cell membrane formation,thereby enhancing rice defenses against drought and salt stress by maintaining lipid homeostasis.展开更多
This paper has provided an effective method to utilize the flter residue. A Y zeolite-containing composite and a fuid catalytic cracking （FCC） catalyst had been successfully prepared by an in-situ crystallization te...This paper has provided an effective method to utilize the flter residue. A Y zeolite-containing composite and a fuid catalytic cracking （FCC） catalyst had been successfully prepared by an in-situ crystallization technology using flter residue and kaolin as raw materials. The samples were characterized by XRD, FT-IR, SEM, and N2 adsorption-desorption techniques and evaluated in a bench FCC unit. In comparison to the reference samples synthesized from single kaolin, the silica/alumina molar ratio, the external surface area, and the total pore volume of the composite increased by 16.2%, 14.5%, and 16.2%, respectively. The catalyst possessed more meso- and macro-pores and more acid sites than the reference catalyst, and exhibited better coke selectivity. The prepared catalyst had the optimum isomerization and aromatization performance. The olefn content in the cracked gasoline obtained over this catalyst was reduced by 5.05 percentage points with the research octane number of gasoline increased by 0.5 units.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2021YFD1200500)STI 2030-Major Projects,China(Grant No.2022ZD04017)Sichuan Department of Science and Technology,China(Grant No.2022JDRC0111).
文摘The tolerance of rice to drought and saline stress is crucial for maintaining yields and promoting widespread cultivation.From an ethyl methanesulfonate(EMS)-mutagenized mutant library,we identified a mutant that is susceptible to osmotic stress,named Osmotic Stress Sensitivity 1(Oss1).Using MutMap sequencing,we characterized the role of a choline transporter-related family gene,CTR4(Choline Transporter-Related 4),in rice’s tolerance to drought and salt stress.CTR4 plays a critical role in regulating membrane lipid synthesis.In knockout mutants,the total membrane lipid content,especially unsaturated fatty acids,was significantly reduced.Compared with the wild type,knockout mutants exhibited decreased membrane lipid stability under drought and salt stress,faster water loss,higher relative electrolyte leakage,and lower levels of proline and soluble sugars,leading to impaired tolerance to drought and salt stress.In contrast,the overexpression of CTR4 enhanced seedling tolerance to drought and saline stress.The overexpression lines displayed lower malondialdehyde levels,reduced relative electrolyte leakage,and slower rates of leaf water loss under stress conditions,thereby improving seedling survival rates during stress.Moreover,lipid synthesis gene expression was down-regulated in CTR4 mutants,potentially exacerbating membrane permeability defects and further compromising stress resistance.These findings suggest that CTR4 mediates choline transport and influences cell membrane formation,thereby enhancing rice defenses against drought and salt stress by maintaining lipid homeostasis.
基金financially supported by the National Natural Science Foundation of China (No.21371055)the Hunan Provincial Colleges and Universities Innovation Platform Open Fund Project (No.15K049)
文摘This paper has provided an effective method to utilize the flter residue. A Y zeolite-containing composite and a fuid catalytic cracking （FCC） catalyst had been successfully prepared by an in-situ crystallization technology using flter residue and kaolin as raw materials. The samples were characterized by XRD, FT-IR, SEM, and N2 adsorption-desorption techniques and evaluated in a bench FCC unit. In comparison to the reference samples synthesized from single kaolin, the silica/alumina molar ratio, the external surface area, and the total pore volume of the composite increased by 16.2%, 14.5%, and 16.2%, respectively. The catalyst possessed more meso- and macro-pores and more acid sites than the reference catalyst, and exhibited better coke selectivity. The prepared catalyst had the optimum isomerization and aromatization performance. The olefn content in the cracked gasoline obtained over this catalyst was reduced by 5.05 percentage points with the research octane number of gasoline increased by 0.5 units.
