A PROTEIN KINASE IS REQUIRED FOR PROPER NODULATION IN THE COMMON BEAN-Rhizobium etli SYMBIOSIS

CLÚA, JOAQUÍN; RÍPODAS, CAROLINA; BATTAGLIA, MARINA; ZANETTI, MARÍA EUGENIA; BLANCO, FLAVIO

Mar del Plata

Congreso; LI SAIB; 2015

SAIB

Phaseolus vulgaris is an agronomical important legume that establishes a nitrogen-fixing symbiosis with Rhizobium etli. In this interaction, bacteria infect the root to reach the nodule, a post-embryonic organ formed by division of cortical cells. A previous study from our laboratory showed that the C1 subunit of the plant nuclear factor NF-Y is a key regulator of infection and nodule organogenesis. In order to identify other factors involved in this signaling pathway, a yeast two hybrid screening was performed. One of the positives clones encodes a protein kinase with a transmembrane domain at the N-terminus. The interaction has been confirmed by both co-immunoprecipitation and bimolecular fluorescence complementation. The protein is distributed between the plasma membrane and the cytoplasm. Post-transcriptional silencing of the kinase by RNAi led to a reduction in the number and size of nodules and affected the infection thread formation in P. vulgaris roots. Interestingly, partner selection between high- and low- quality symbiotic partners was also affected in coinoculation experiments. Taken together, these results suggest that this gene is required for rhizobial infection, nodule organogenesis and the molecular mechanism underlying bacterial strain preference