A high sensitive long period fiber grating（LPFG） sensor for the detection of nitrite is proposed, which is realized by coating multiple poly（sodium 4-styrensulfonate）（PSS） and poly（diallyldimethylammonium） chl...A high sensitive long period fiber grating（LPFG） sensor for the detection of nitrite is proposed, which is realized by coating multiple poly（sodium 4-styrensulfonate）（PSS） and poly（diallyldimethylammonium） chloride （PDDA） layers on the fiber grating surface. The sensitivity of this LPFG sensor is maximum when the number of assembled layers is 70. Under this condition, a nitrite concentration of 3×10^-3 mol/L, which is lower than the National Food Additive Standard, 4.2×10^-3 mol/L, can be distinguished. The sensitivity is further increased by 30% when nitrite was determined in the sucrose solution with a concentration of 65%, which provides a new solution for the best refraction index approaching matched index of the fiber cladding. Compared with chemical methods, this nitrite detection technology offers some advantages, such as high accuracy, non toxicity, high speed, low cost, without chemical reagent, and is suitable for foodstuff security detection.展开更多
Transcription activator-like effector （TALE） nucleases （TALENs） are increasingly used as a powerful tool for genome edit- ing in a variety of organisms. We have previously cloned the TALE-coding gene avrXa23 from ...Transcription activator-like effector （TALE） nucleases （TALENs） are increasingly used as a powerful tool for genome edit- ing in a variety of organisms. We have previously cloned the TALE-coding gene avrXa23 from Xanthomonas oryzae pv. oryzae and developed an AvrXa23-based assembly system for designer TALEs or TALENs. Here, we exploit TALENs to induce mutagenesis of the rice ethylene response factor （ERF） transcription factor OsERF922 for testing the gene-editing efficiency of AvrXa23-based TALENs system. A pair of TALENs （T-KJ9/KJ 10） was assembled and their nuclease activities were first confirmed in rice protoplast transient assay. The TALENs-expressing construct pT-KJ9/KJ10 was then used for rice transformation. We observed targeting somatic mutagenesis frequency of 15.0% in positive transgenic rice calli and obtained two mutant plants with nucleotide deletion or insertion at the designer target region. Our work demonstrates that the AvrXa23-based TALENs system can be used for site-specific genome editing in rice.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.60707016 and 60807030)
文摘A high sensitive long period fiber grating（LPFG） sensor for the detection of nitrite is proposed, which is realized by coating multiple poly（sodium 4-styrensulfonate）（PSS） and poly（diallyldimethylammonium） chloride （PDDA） layers on the fiber grating surface. The sensitivity of this LPFG sensor is maximum when the number of assembled layers is 70. Under this condition, a nitrite concentration of 3×10^-3 mol/L, which is lower than the National Food Additive Standard, 4.2×10^-3 mol/L, can be distinguished. The sensitivity is further increased by 30% when nitrite was determined in the sucrose solution with a concentration of 65%, which provides a new solution for the best refraction index approaching matched index of the fiber cladding. Compared with chemical methods, this nitrite detection technology offers some advantages, such as high accuracy, non toxicity, high speed, low cost, without chemical reagent, and is suitable for foodstuff security detection.
基金supported by the grant from the Major Science and Technology Project to Create New Crop Cultivars Using Gene Transfer Technology of China (2014ZX0801001B)the National Natural Science Foundation of China (31171812)
文摘Transcription activator-like effector （TALE） nucleases （TALENs） are increasingly used as a powerful tool for genome edit- ing in a variety of organisms. We have previously cloned the TALE-coding gene avrXa23 from Xanthomonas oryzae pv. oryzae and developed an AvrXa23-based assembly system for designer TALEs or TALENs. Here, we exploit TALENs to induce mutagenesis of the rice ethylene response factor （ERF） transcription factor OsERF922 for testing the gene-editing efficiency of AvrXa23-based TALENs system. A pair of TALENs （T-KJ9/KJ 10） was assembled and their nuclease activities were first confirmed in rice protoplast transient assay. The TALENs-expressing construct pT-KJ9/KJ10 was then used for rice transformation. We observed targeting somatic mutagenesis frequency of 15.0% in positive transgenic rice calli and obtained two mutant plants with nucleotide deletion or insertion at the designer target region. Our work demonstrates that the AvrXa23-based TALENs system can be used for site-specific genome editing in rice.
