Genetic complementation of rhizobial nod mutants with Frankia DNA: artifact or reality?-猫眼课题宝

根瘤菌点头突变体与 Frankia DNA 的遗传互补：人工制品还是现实？

DOI：

10.1007/s004380050877

发表时间：

1998

期刊：

Molecular and General Genetics MGG

影响因子：

通讯作者：

中科院分区：

文献类型：

作者：

H. Cérémonie;B. Cournoyer;F. Maillet;P. Normand;M. Fernandez

摘要关于根瘤菌nod突变体利用Frankia DNA进行遗传互补，已有两篇不同的报道。1991年有报道称，假设的Frankia cosmid文库克隆恢复了豆科根瘤菌生物变种viciaenodD::Tn5的正常结瘤特性，但没有发表支持的序列数据。1992年，另一组报告说，没有发现任何证据表明各种根瘤菌结突变体与法兰克菌DNA （nodA、nodB和nodC）具有功能性互补。9个Nod−R的互补测试。leguminosarum bv。因此，使用pLAFR3中的Frankia基因文库对牛痘或meliloti Sinorhizobium Tn5突变体（nodA−,nodB−,nodC−,nodD−,nodF−,nodL−,nodH−）进行了分析，以澄清这一情况。对三亲本杂交获得的根瘤菌转接合体进行了筛选，以恢复其寄主植物紫薇（Vicia sativa）的结瘤表型。黑草或苜蓿。用豆科苜蓿的转接合体接种植株，观察到结瘤现象。viciaenodC:: Tn5突变。对Nod+根瘤菌转接合物进行了分离和分析。这些转接合子的Nod+表型被发现是由于Tn5切除/转位。没有发现任何使用的突变体的功能互补，这表明nod突变体与Frankia DNA的根瘤菌互补不太可能发生。

Abstract Two divergent reports have been published on the genetic complementation of rhizobial nod mutants using Frankia DNA. In 1991 putative Frankia cosmid library clones were reported to restore normal nodulation properties to Rhizobium leguminosarum biovar viciaenodD::Tn5, but no supporting sequence data were published. In 1992 a second group reported a failure to find any evidence of functional complementation of various rhizobial nod mutants by Frankia DNA (nodA, nodB and nodC). Complementation tests of nine Nod−R. leguminosarum bv. viciae or Sinorhizobium meliloti Tn5 mutants (nodA−, nodB−, nodC−, nodD−, nodF −, nodL−, nodH−) were thus performed using a Frankia gene library in pLAFR3 to clarify this situation. Rhizobial transconjugants obtained by tri-parental matings were screened for restoration of the nodulation phenotype on their host plants, Vicia sativa subsp. nigra or Medicago sativa. Nodulation was observed on plants inoculated with transconjugants of the R. leguminosarum bv. viciaenodC::Tn5 mutant. The Nod+ rhizobial transconjugants were isolated and analysed. The Nod+ phenotype of these transconjugants was found to be due to Tn5 excision/transposition. No functional complementation was found with any of the mutants used, suggesting that rhizobial complementation of nod mutants with Frankia DNA is unlikely to occur.

Homologs of the Xenopus developmental gene DG42 are present in zebrafish and mouse and are involved in the synthesis of Nod-like chitin oligosaccharides during early embryogenesis.