Laplaze Laurent, Gherbi Hassen, Duhoux Emile, Pawlowski Katharina, Auguy Florence, Guermache Fathia, Franche Claudine, Bogusz Didier
Department of Plant Sciences, University of Cambridge, UK.
Plant Mol Biol. 2002 May;49(1):81-92. doi: 10.1023/a:1014415003714.
A clone for a type 1 metallothionein (cgMT1) was isolated from a Casuarina glauca nodule cDNA library. The corresponding gene belongs to a small family and is highly expressed in roots and nitrogen-fixing nodules, whereas low expression was observed in aerial parts of the plant. The promoter region of cgMT1 was isolated and fused to the beta-glucuronidase (gus) gene. Transgenic Casuarinaceae plants showed that the cgMT1 promoter was most active in roots and in the oldest region of the shoot. In situ hybridization indicated that in nodules cgMT1 transcript is present in mature Frankia-infected cells and in the pericycle. Possible roles for cgMT1 in symbiotic and nonsymbiotic tissues are discussed.
从木麻黄根瘤cDNA文库中分离出一个1型金属硫蛋白（cgMT1）的克隆。相应的基因属于一个小家族，在根和固氮根瘤中高度表达，而在植物地上部分表达较低。分离出cgMT1的启动子区域并将其与β-葡萄糖醛酸酶（gus）基因融合。转基因木麻黄科植物表明，cgMT1启动子在根和茎的最老区域活性最高。原位杂交表明，在根瘤中，cgMT1转录本存在于成熟的被弗兰克氏菌感染的细胞和中柱鞘中。讨论了cgMT1在共生和非共生组织中的可能作用。
