STRUCTURE AND EXPRESSION OF THE LIGNIN O-METHYLTRANSFERASE GENE FROM ZEA-MAYS L
STRUCTURE AND EXPRESSION OF THE LIGNIN O-METHYLTRANSFERASE GENE FROM ZEA-MAYS L
复制标题
DOI：
10.1007/bf00027157
复制
发表时间：
1992-12-01
影响因子：
5.1
通讯作者：
RIGAU, J
中科院分区：
文献类型：
--
作者：
COLLAZO, P;MONTOLIU, L;RIGAU, J
报道了玉米木质素O-甲基转移酶（OMT）cDNA和同源基因组克隆的分离和鉴定。通过对玉米根cDNA文库的差异筛选，获得了该cDNA克隆。Southem分析表明，该蛋白质由一个基因编码。该基因组序列含有一个916 bp的内含子。从DNA推导的蛋白质序列与最近报道的苜蓿和白杨的木质素-双特异性咖啡酸/5-羟基阿魏酸OMT具有显著的同源性。它还与牛松果体的OMT和紫色非硫光合细菌具有同源性。该基因的mRNA以不同水平存在于植物的不同器官中，在根的伸长区中检测到最高的积累。来自含有玉米OMT cDNA的克隆的细菌提取物显示出与植物提取物中存在的活性相当的咖啡酸甲基化为阿魏酸的活性。这些结果表明，所描述的基因编码咖啡酸3-O-甲基转移酶（COMT）参与玉米的木质素生物合成。
The isolation and characterization of cDNA and homologous genomic clones encoding the lignin O-methyltransferase (OMT) from maize is reported. The cDNA clone has been isolated by differential screening of maize root cDNA library. Southem analysis indicates that a single gene codes for this protein. The genomic sequence contains a single 916 bp intron. The deduced protein sequence from DNA shares significant homology with the recently reported lignin-bispecific caffeic acid/5-hydroxyferulic OMTs from alfalfa and aspen. It also shares homology with OMTs from bovine pineal glands and a purple non-sulfur photosynthetic bacterium. The mRNA of this gene is present at different levels in distinct organs of the plant with the highest accumulation detected in the elongation zone of roots. Bacterial extracts from clones containing the maize OMT cDNA show an activity in methylation of caffeic acid to ferulic acid comparable to that existing in the plant extracts. These results indicate that the described gene encodes the caffeic acid 3-O-methyltransferase (COMT) involved in the lignin biosynthesis of maize.