生长素结合蛋白ABP1基因在棉纤维伸长中的功能

On functions of auxin binding protein ABP1 gene in cotton fiber elongation

以‘湘杂棉14’为材料,采用RT–PCR方法克隆了棉花ABP1基因全长cDNA序列。序列全长792 bp,与GenBank中陆地棉ABP1基因序列的同源性为99%。半定量分析表明,该基因在棉花叶、花及纤维中都有表达,其中叶中的表达量最高,花和纤维中的表达量稍低。ABP1基因在纤维快速伸长期表达水平较高,纤维发育的其他时期的表达水平较低。将ABP1基因cDNA构建成棉花ABP1过表达载体,并以NPT II作为选择标记,经农杆菌介导转化棉花,获得了6株Kan抗性植株,其中3株ABP1表达水平提高。ABP1过表达植株生长发育正常,但纤维长度变化不显著,说明ABP1棉纤维细胞中提高表达水平对其细胞伸长没有显著作用。

In this paper, using the ＇Xiangzamian 14＇ as materials, we have cloned the full-length cDNA sequence of ABP1 gene of cotton by RT-PCR method. The sequence is 792 bp in length and shares a 99% identity with the cDNA sequence ofABP1 gene of the Upland Cotton in GenBank. Semi quantitative analysis shows that, the gene is expressed in cotton leaves, flowers and fibers, the expression amount in leaves is the highest, those in flowers and fibers are a little lower ABP1 gene is highly expressed in the term of rapid elongation of cotton fiber while it is lower expressed in other terms of fiber development .By constructing the ABP1 gene cDNA into the carrier of the cotton ABP1 over expression vector and taking the NPT II as selection marker, by Agrobacterium mediated transformation of cotton, we have obtained 6 Kan resistant plants, including 3 plants whose ABP1 expression level has been raised. The plants with ABP1 overexpressing show normal growth and development, but the change of their fiber length is not significant, which indicates that the increase of the expression level in ABP1 cotton fiber cells has no significant effect on the cell elongation The results have shown that ABP1 gene may not be a key regulate factor in fiber elongation.