通过卡那霉素选择体系再生可育小麦转基因植株

使用卡那霉素作为选择剂建立起一套有效的小麦转化体系,预培养3d的未成熟胚在基因枪轰击前后进行高渗处理,轰击后于26℃、黑暗条件培养2周,然后用150mg/L硫酸卡那霉素选择培养2周,再转至含150mg/L硫酸卡那霉素的再生培养基进行光照培养。再生植株在温室中长出2～3片新叶后用2.5％硫酸卡那霉素水溶液喷洒;4周内,非转化体完全白化并枯萎,而转基因植株生长正常,用水稻Actinl启动子控制nptⅡ基因,卡那霉素选择体系的平均转化频率达到2.6％,高渗处理明显促进瞬间表达效果和稳定转化频率。目前已得到23个转基因小麦株系,大多数已经产生种子。Southern分析表明这些转基因株系均整合有不同拷贝的nptⅡ基因。

Synthesis of kanamycin A derivatives by regioselective masking drug resistant enzymes targeting hydroxyl groups

The 3＇-OH, 4＇-OH and 2＂-OH of kanamycin A were modified in search of new aminoglycosides to overcome resistant enzymes, ANTs and APHs. The key intermediate was a dibenzylidene-protected derivative of kanamycin A. The aimed sites were masked by benzyl, methyl and allyl groups. Multi-step reactions gave the desired aminoglycoside derivatives but showed less antibiotic activity than kanamycin A.