Isolation and characterisation of laccase cDNAs from meristematic and stem tissues of ryegrass (Lolium perenne)
Isolation and characterisation of laccase cDNAs from meristematic and stem tissues of ryegrass (Lolium perenne)
复制标题
DOI：
10.1016/s0168-9452(02)00035-3
复制
发表时间：
2002-06-01
期刊：
影响因子：
5.2
通讯作者：
Rasmussen, SK
中科院分区：
文献类型：
--
作者：
Gavnholt, B;Larsen, K;Rasmussen, SK
植物漆酶被认为参与木质素的分解聚合。本文报道了单子叶植物漆酶的首次克隆。五个不同的漆酶编码的cDNA序列被确定从黑麦草（多年生黑麦草），四个从茎和一个分生组织。三个cDNA含有完整的编码序列; LpLAC 5 -4和LpLAC 5 -6来自茎，LpLAC 2 -1来自分生组织。LpLAC 5 -4编码610个氨基酸的多肽，具有14个潜在的N-糖基化位点，计算的pI值为5.0。在LpLAC 5 -4中缺乏N-末端信号肽表明成熟蛋白位于细胞内。已分离到一个基因组克隆gLpLAC 5 -4，它代表了植物漆酶基因的第一个外显子-内含子结构和启动子序列。LpLAC 5 -6 cDNA编码579个氨基酸的蛋白质，具有分泌蛋白质的N-末端信号肽特征，13个潜在的N-糖基化位点，pI值为9.0。LpLAC 2 -1是在分生组织文库中发现的唯一漆酶。该cDNA编码578个氨基酸的蛋白质，预测的pI为5.8，9个推定的N-糖基化位点，和一个N-末端信号肽。黑麦草漆酶的差异表达和严格的转录控制下。序列分析表明，黑麦草基因组编码超过25个不同的漆酶基因。植物漆酶分布在不同的类群中，而不是种内密切相关。漆酶的高度异质性表明，在种子植物分化为裸子植物、单子叶植物和双子叶植物之前和之后，基因重复事件不断发生。(C)2002爱思唯尔科学爱尔兰有限公司保留所有权利。
Plant laccases are believed to be involved in dehydrogenative polymerisation of lignin. We report here the first cloning of monocot laccases. Five different laccase-encoding cDNA sequences were identified from ryegrass (Lolium perenne); four from stem and one from meristematic tissue. Three cDNA's contained entire coding sequences; LpLAC5-4 and LpLAC5-6 from stem, and LpLAC2-1 from meristem. LpLAC5-4 encodes a polypeptide of 610 amino acids with 14 potential N-glycosylation sites, and a calculated pI value of 5.0. Lack of an N-terminal signal peptide in LpLAC5-4 suggests that the mature protein is located intracellularly. A genomic clone, gLpLAC5-4, has been isolated and represents the first exon-intron structure and promoter sequence of a plant laccase gene. LpLAC5-6 cDNA encodes a protein of 579 amino acids with an N-terminal signal peptide characteristic of secreted proteins, 13 potential N-glycosylation sites, and a pI value of 9.0. LpLAC2-1 was the only laccase found in a meristematic library. The cDNA encodes a protein of 578 amino acids with a predicted pI of 5.8, 9 putative N-glycosylation sites, and an N-terminal signal peptide. Ryegrass laccases are differentially expressed and are under tight transcriptional control. Sequence analyses have shown that the ryegrass genome encodes more than 25 different laccase genes. Plant laccases are distributed in different groups rather than being closely intraspecies related. High heterogeneity of plant laccases indicates that gene duplication events have occurred continuously before and after divergence of seedplants into gymnosperms, monocots, and dicots. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.