Gene for a protein capable of enhancing lateral root formation

Analysis of genes preferentially expressed in hairy roots caused by infecti on with Agrobacterium rhizogenes has provided insights into the regulation of lateral root formation. A hairy root preferential cDNA, HR7, has been cl oned from hairy roots of Hyoscyamus niger. HR7 encodes a novel protein part ially homologous to a metallocarboxypeptidase inhibitor and is expressed ex clusively in the primordium and base of lateral roots in hairy roots. Overe xpression of HR7 in transgenic roots of H. niger dramatically enhances the frequency of lateral root formation. The results of this study indicate tha t expression of HR7 plays a critical role in initiating lateral root format ion. (C) 1999 Federation of European Biochemical Societies.