Accumulation of Transcripts Encoding a Lipid Transfer-Like Protein During Deformation of Nodulation-Competent Vigna unguiculata Root Hairs. Andrea Krause, L.B.M.P.S., Universite de Geneve, 1, ch. de I'lmperatrice, 1292 Chambesy/Geneva, Switzerland. Christian J. A. Sigrist(1), Irmtraut Denning(1), Hans Sommer(2), and William J. Broughton(1). (1)L.B.M.P.S., Universite de Geneve, 1, ch. de I'lmperatrice, 1292 Chambesy/Geneva, Switzerland, and (2) Max-Planck-lnstitute for Plant Breeding, Carl-von-Linne-Weg, 50829 Cologne, Germany. MPMI 7:411-418. Accepted 11 March 1994. Copyright 1994 The American Phytopathological Society.

A cDNA library was constructed from RNA of Vigna unguiculata root hairs harvested 1 day and 4 days after inoculation with Rhizobium sp. NGR234. A heterologous probe was used to identify a cDNA clone, the predicted 99-amino-acid sequence of which shares homology with a nonspecific lipid transfer protein (LTP) of Hordeum vul-gare. Other characteristics, including an estimated molecular weight of 10.4 kD, an isoelectric point of 8.6, and a signal peptide with a hydrophobic region at the amino-terminal end, are shared by most LTPs. A transcript of 630 nt was found in all tissues tested, except nodules. Levels of mRNA increased in root hairs 24 hr after treatment with Rhizobium sp. NGR234, with different hormones, or with Nod factors. Amounts of transcripts were dependent on the concentration of Nod factors. Accumulation of transcripts during nodule development correlated with root hair deformation, the first visible step in the RhizobiuniAcgume symbiosis.