GRP1.8-反义pt4CL1基因对巨尾桉木质素含量的影响

桉树是桃金娘科桉树属(Eucalyptus）植物的统称，是制浆造纸的主要原料之一，但是桉树中含有大量木质素，木质素的存在会严重影响纸浆的质量。4-香豆酸颐辅酶A 连接酶(4CL）是木质素单体生物合成的关键酶之一，抑制4CL 基因的表达，可以有效降低植物中木质素的含量。通过根癌农杆菌介导的叶盘转化法，将形成层定位启动子GRP1.8 融合的杨树反义4-香豆酸:辅酶A 连接酶基因导入巨尾桉，经卡那霉素筛选和PCR 鉴定，获得9 株转基因阳性植株。通过4CL 酶活性测定和木质素、纤维素含量的分析，发现转基因组培苗的4CL 酶活性比对照植株下降了44%，温室转基因幼苗中硫酸木质素含量下降了16%。

GRP1.8-antisense pt4CL1 changes the content of lignintransformed Eucalyptus grandis E. ophylla

Eucalyptus is one of the main raw material for pulp. 4-coumarate: coenzyme A ligase is one of the keyenzymes in the biosynthesis of lignin monomer. Inhibited the expression of 4CL gene can effectively reduce the content ofthe lignin in plants. The plant expression binary vector with glycine rich protein (GRP1.8) fused antisense 4-coumarate:CoA ligase (4CL1) gene from Populus tomentosa was transformed to Eucalyptus grandisE. ophylla. Nine transgenic plantswere obtained by kanamyic resistant selection and PCR amplification selection. The 4CL1 enzyme activity of transgenicplants in tissue culture decreased up to 44% compared with wild-type plants. The klason lignin content of regeneratedEucalyptus seedlings in greenhouse decreased up to 16%.