棉花漆酶基因在转基因新疆杨中的表达及其对木质素合成的影响

以新疆杨叶柄为外植体,利用农杆菌法将棉花漆酶基因GaLAC1导入新疆杨.PCR,Soutllern杂交证明外源基因已经整合到杨树基因组中.漆酶活性分析表明转基因植株中漆酶活性较非转基因对照显著提高.与对照植株相比,转基因新疆杨茎段中总木质素的含量有不同程度的增加,最高达21.5%.木质素的组织化学染色进一步证实了GaLAC1的过量表达能够导致转基因植株中总木质素含量的增加.实验结果表明GaLAC1参与了植物体内木质素的合成,这是首次成功利用转基因植物证实植物漆酶基因参与木质素合成的报道.

COTTON LACCASE GENE OVEREXPRESSION IN TRANSGENIC Populus alba var. pyramidalis AND ITS EFFECTS ON THE LIGNIN BIOSYNTHESIS IN TRANSGENIC PLANTS

Using petioles as explants, a cotton laccase cDNA (GaLA C1) was introduced into Populus alba var. pyramidalis by A. tumefaciens-mediated transformation. PCR and Southern blot analysis indicated that transgene was stably integrated into the genome of transformants. Enzyme assay showed that laccase activity was obviously increased in transformants. As compared with untransformed control, total lignin content in all tested transgenic lines was elevated in varying degrees (as highest as 21.5%). Histochemical staining of lignin further confirmed that overexpressing GaLA C1 could result in increased lignin content in transformants. Together, our data strongly suggested that GaLA C1 may participate in lignin synthesis and this is the first direct transgenic evidence for the involvement of plant laccases in lignification.