Early legume responses to inoculation with Rhizobium sp. NGR234.
Interactions between legumes and rhizobia are controlled by the sequential exchange of symbiotic signals. Two different techniques, 2D-PAGE electrophoresis and differential display were used to study the effects of rhizobial signals on legume development. Application of variously substituted lipo-oligo-saccharidic Nod-factors to roots of Vigna unguiculata resulted in changes in the phosphorylation patterns of microsomal proteins. Reliable amino-acid sequences were obtained for one Nod-factor enhanced protein which was highly homologous to the 57-kDa subunit from Arabidopsis thaliana vacuolar membrane H(+)-ATPase. Immuno-blotting techniques demonstrated that Nod-factors cause rapid and massive increases of this enzyme in treated roots, suggesting that H(+)-ATPases play symbiotic roles. Concomitantly, we used differential display (DD) techniques on mRNA isolated from root-hairs to analyse early root responses to NGR234. Significant matches of several DD clones to known sequences were found. Clone D2.62 was homologous to a multitude of receptor kinases including S receptor-like kinases of A. thaliana and clone D4.1 showed similarities to Lotus japonicus phosphatidylinositol transfer-like protein III and late nodulin 16. Independent confirmatory analyses of these differentially expressed clones indicated expression at very low levels.
Boukli
N M
NM
LBMPS, Université de Genève, Sciences III, 30 quai Ernest-Ansermet, 1211 Genève 4, Switzerland.
Sunderasan
E
E
Bartsev
A
A
Hochstrasser
D
D
Perret
X
X
Bjourson
A J
AJ
Krause
A
A
Broughton
W J
WJ
D002458:Cell Fractionation / Q000379:methods; D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D015180:Electrophoresis, Gel, Two-Dimensional; D007887:Fabaceae / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D020869:Gene Expression Profiling; D015151:Immunoblotting; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D040901:Proteomics; D012333:RNA, Messenger / Q000378:metabolism; D012231:Rhizobium / Q000502:physiology*; D020539:Sequence Analysis, Protein; D017423:Sequence Analysis, RNA; D015398:Signal Transduction; D013559:Symbiosis
D012333:RNA, Messenger