MESSENGER-RNA FROM DIVERSE CLASSES OF ALFALFA LEGHEMOGLOBIN GENES SHOW A SIMILAR PATTERN OF SPATIAL EXPRESSION IN SYMBIOTIC ROOT-NODULES

The spatial expression of specific classes of leghemoglobin mRNA corre sponding to divergent classes of alfalfa leghemoglobin (Lb) isomers wa s analyzed by in situ hybridization of oligonucleotide probes to root nodule cryosections. The aim of this study was to determine whether st ructural changes in the nodule may contribute to the shift in Lb prote in isomer expression observed during root nodule development. The co-l ocalization of the diverse Lb mRNAs suggests that this is unlikely to be the case.