细菌mtl-D朌基因的克隆及在转基因八里庄杨中的表达

运用ＰＣＲ方法克隆了大肠杆菌１－磷酸甘露醇脱氢酶（ｍｔｌ－Ｄ）基因，序列分析表明与已发表序列相比，除第 ４１６位密码子由 ＡＡＡ代替 ＣＡＴ、相应的氨基酸由 Ｌｙｓ代替 Ｈｉｓ外，其他部分均相同。该基因插入植物双元载体中，经土壤农杆菌介导导入八里庄杨［１］，经卡那霉素筛选后再经盐胁迫筛选获得一批较高耐盐性的转化植株，在附加 ０.６％ＮａＣｌ的培养基中生长良好，而对照在附加 ０．４％ ＮａＣｌ的培养基中不能存活。对转化植株进行的 ＰＣＲ检测、Ｎｏｒｔｈｅｒｎ杂交，说明外源基因已整合到染色体上并且有转录。

Cloning of E. Coli mtl-D Gene and Its Expression in Transgenic Balizhuangyang (Populus)

E. coli 1-phosphate mannitol dehydrogenase gene (mtl-D) was cloned using PCR method. Sequence analysis showed that the gene was the same as the published one except that codon CAT at position 416 was replaced by AAA and resulted in a Lys residue instead of His. This gene (mtl-D) was inserted in a binary vector and transformed into populas via agrobacteria. Several transgenic plants grow very well in 0.6% NaCl while controls can not survive even in 0.4% NaCl. PCR analysis and Northern blotting indicated that foreign gene was integrated into the genome of transgenic plant and transcribed successfully.