小麦根高亲和NO_3~-转运体全长基因(TaNRT2.1)的克隆和鉴定

 在前期获得的 pTaAF 的工作基础上,采用 RACE 方法进一步克隆和鉴定了小麦根 NO3 转运体全长基因-(TaNRT2.1)。将TaNRT2.1和已知的硝态氮转运体基因家族进行同源性比较,指出TaNRT2.1属于HATS中的NRT2家族。Southern　印迹揭示小麦基因组中有1个TaNRT2.1拷贝。Northern　分析示出硝态氮可瞬时诱导TaNRT2.1　mRNA积累,NO 处理 1 h　TaNRT2.1　mRNA很快增加,4　h 达到最大,24　h恢复至诱导前水平,具根专一表达特点。 - 3

Cloning and Characterization of a High-Affinity Nitrate Transporter Full-cDNA (TaNRT2.1) from Wheat Roots

A new nitrate transporter gene (TaNRT2.1) that is expressed in wheat roots was identified, and cloned. Based on the sequence of the pTaAF fragment, a full-length cDNA clone was obtained from wheat root RNA by using 5'- and 3'- RACE-PCR. Homologous analyses, using TaNRT2 and known HATS sequences of higher plants, indicated that this gene was amember of the NRT2 family in HATS. Southern blotting revealed that TaNRT2.1 is present as a single copy in the wheat genome. Northern analysis demonstrated that accumulation of TaNRT2.1 mRNA was transiently induced by nitrate, showing a rapid increase by 1h following NO3 treatment, reaching a maximum at 4 h after treatment, and then decreased to the original - level by 24 h. TaNRT2.1 mRNA accumulated in roots, but was not present in leaves.