Establishment of a highly efficient regeneration system for the mature embryo of wheat will provide a convenient tool for wheat tissue culture and transformation, thereby facilitating the transformation of foreign gen...Establishment of a highly efficient regeneration system for the mature embryo of wheat will provide a convenient tool for wheat tissue culture and transformation, thereby facilitating the transformation of foreign genes into wheat. By using the mature embryos derived from 20 different wheat lines including Shi 4185, Yumai 66, Lunxuan 987, CB037, Yangmai 6, Xinchun 9, Bobwhite, Han 6172, Zheng 9023, Jimai 20, Ningchun 4, and Jing 411, the effects of some factors including inoculation methods, initiating culture media, organic additives, antioxidants, and auxins on the regeneration from the explants were evaluated. The results indicated that the scraping embryo culture was better than the whole embryo culture, the Aa medium was better than the SD2 medium and dicamba was better than 2,4-D in increasing the regeneration frequency. An Adi medium was established in this study by adding silver nitrate, cysteine, ascorbic acid, dicamba, glutamine into the Aa medium at the concentration of 4,40, 100, 2, and 5 mg L^-1, respectively. By using the Adi medium and the scraping technique, the regeneration frequencies of the mature embryos of CB037, Lunxuan 987, Hart 6172, Yangmai 6, Bobwhite, Zheng 9023, Shi 4 185, and Jimai 20 became 85.6, 60,1, 46.0, 42.1,42.0, 34.0, 33.0, and 32.0%, respectively, which were about 5-8 times higher than that obtained from the conventional culture mediums and techniques. This novel regeneration system could be helpful in wheat transformation.展开更多
Fructan is not only a carbon source for storage but also plays an important role as anti-stress agents in many plant species. Complex fructans having both β-(2,1)- and β-(2,6)-linked fructosyl units accumulate i...Fructan is not only a carbon source for storage but also plays an important role as anti-stress agents in many plant species. Complex fructans having both β-(2,1)- and β-(2,6)-linked fructosyl units accumulate in Triticeae plants commonly. Three enzymes (sucrose: sucrose 1-fructosyltransferase, 1-SST, EC: 2.4.1.99; sucrose: fructan 6-fructosyltransferase, 6- SFT, EC: 2.4.1.10; and fructan: fructan 1-fructosyltransferase, 1-FFT, EC: 2.4.1.100) were involved in fructan biosynthesis in Triticeae plant species. We successfully isolated these genes from tetraploid wheat (Triticum turgidum, genotype: AABB), common wheat (Triticum aestivum L., genotype: AABBDD) and three wild relatives of common wheat, Triticum urartu Thum. (the origin of the AA genome), Aegilops speltoides (Tausch) Gren. (the putative source of the SS genome) and Aegilops tauschii Coss. (the source of the DD genome). Sequence analysis revealed that all the FBEs (fructan biosynthetic enzymes) had three highly conserved functional motifs except 1-SST (EU981912) from tetraploid wheat species only with conserved DPNG. Low pI (isoelectric point) and potential N-glycosylation sites were predicted, which were crucial for protein compartmentation and post-translational process. Analysis on subcelluar localization signals showed that only 6-SFT had vacuolar-directed signal. Sequences alignment result showed that 1-SST and 1-FFT were more conservative and had closer relationship each other, while 6-SFT was more active during the evolution processing. According to the syntenic relationship between wheat and rice genome, FBEs were predicated to be located on the homeologous group 6 and group 2 chromosomes. Expression profile confirmed that expression of all the three FBEs were drought-stress induced. This study can assist to establish a useful theoretical platform for cold- or drought-tolerant improvement of wheat by modulating FBEs expression.展开更多
基金funded by the National Natural Science Foundation of China (30971776)the National Transgenic Organism Research Program of China(2008ZX08010-004)
文摘Establishment of a highly efficient regeneration system for the mature embryo of wheat will provide a convenient tool for wheat tissue culture and transformation, thereby facilitating the transformation of foreign genes into wheat. By using the mature embryos derived from 20 different wheat lines including Shi 4185, Yumai 66, Lunxuan 987, CB037, Yangmai 6, Xinchun 9, Bobwhite, Han 6172, Zheng 9023, Jimai 20, Ningchun 4, and Jing 411, the effects of some factors including inoculation methods, initiating culture media, organic additives, antioxidants, and auxins on the regeneration from the explants were evaluated. The results indicated that the scraping embryo culture was better than the whole embryo culture, the Aa medium was better than the SD2 medium and dicamba was better than 2,4-D in increasing the regeneration frequency. An Adi medium was established in this study by adding silver nitrate, cysteine, ascorbic acid, dicamba, glutamine into the Aa medium at the concentration of 4,40, 100, 2, and 5 mg L^-1, respectively. By using the Adi medium and the scraping technique, the regeneration frequencies of the mature embryos of CB037, Lunxuan 987, Hart 6172, Yangmai 6, Bobwhite, Zheng 9023, Shi 4 185, and Jimai 20 became 85.6, 60,1, 46.0, 42.1,42.0, 34.0, 33.0, and 32.0%, respectively, which were about 5-8 times higher than that obtained from the conventional culture mediums and techniques. This novel regeneration system could be helpful in wheat transformation.
基金funded by the National High-Tech R&D Program of China (863 Program of China,2007AA10Z129)
文摘Fructan is not only a carbon source for storage but also plays an important role as anti-stress agents in many plant species. Complex fructans having both β-(2,1)- and β-(2,6)-linked fructosyl units accumulate in Triticeae plants commonly. Three enzymes (sucrose: sucrose 1-fructosyltransferase, 1-SST, EC: 2.4.1.99; sucrose: fructan 6-fructosyltransferase, 6- SFT, EC: 2.4.1.10; and fructan: fructan 1-fructosyltransferase, 1-FFT, EC: 2.4.1.100) were involved in fructan biosynthesis in Triticeae plant species. We successfully isolated these genes from tetraploid wheat (Triticum turgidum, genotype: AABB), common wheat (Triticum aestivum L., genotype: AABBDD) and three wild relatives of common wheat, Triticum urartu Thum. (the origin of the AA genome), Aegilops speltoides (Tausch) Gren. (the putative source of the SS genome) and Aegilops tauschii Coss. (the source of the DD genome). Sequence analysis revealed that all the FBEs (fructan biosynthetic enzymes) had three highly conserved functional motifs except 1-SST (EU981912) from tetraploid wheat species only with conserved DPNG. Low pI (isoelectric point) and potential N-glycosylation sites were predicted, which were crucial for protein compartmentation and post-translational process. Analysis on subcelluar localization signals showed that only 6-SFT had vacuolar-directed signal. Sequences alignment result showed that 1-SST and 1-FFT were more conservative and had closer relationship each other, while 6-SFT was more active during the evolution processing. According to the syntenic relationship between wheat and rice genome, FBEs were predicated to be located on the homeologous group 6 and group 2 chromosomes. Expression profile confirmed that expression of all the three FBEs were drought-stress induced. This study can assist to establish a useful theoretical platform for cold- or drought-tolerant improvement of wheat by modulating FBEs expression.