Barnett M J, Long S R
Department of Biological Sciences, Stanford University, California 94305-5020.
J Bacteriol. 1990 Jul;172(7):3695-700. doi: 10.1128/jb.172.7.3695-3700.1990.
Rhizobium meliloti nodulation (nod) genes are expressed when activated by trans-acting proteins in the NodD family. The nodD1 and nodD2 gene products activate nod promoters when cells are exposed to plant-synthesized signal molecules. Alternatively, the same nod promoters are activated by the nodD3 gene when nodD3 is carried in trans along with a closely linked global regulatory locus, syrM (symbiotic regulator) (J. T. Mulligan and S. R. Long, Genetics 122:7-18, 1989). In this article we report the nucleotide sequence of a 2.6-kilobase SphI fragment from R. meliloti SU47 containing syrM. Expression from this locus was confirmed by using in vitro transcription-translation assays. The open reading frame encoded a protein of either 33 or 36 kilodaltons whose sequence shows similarity to NodD regulatory proteins.
当被根瘤菌属苜蓿中华根瘤菌(Rhizobium meliloti)结瘤(nod)基因家族中的反式作用蛋白激活时,这些基因会表达。当细胞暴露于植物合成的信号分子时,nodD1和nodD2基因产物会激活nod启动子。另外,当nodD3与紧密连锁的全局调控基因座syrM(共生调节因子)一起反式携带时,相同的nod启动子会被nodD3基因激活(J. T. Mulligan和S. R. Long,遗传学122:7 - 18,1989)。在本文中,我们报告了来自苜蓿中华根瘤菌SU47的一个包含syrM的2.6千碱基SphI片段的核苷酸序列。通过体外转录 - 翻译分析证实了该基因座的表达。开放阅读框编码了一种33或36千道尔顿的蛋白质,其序列与NodD调节蛋白具有相似性。