INSTITUTO DE BIOTECNOLOGIA Y BIOLOGIA MOLECULAR
Unidad Ejecutora - UE
congresos y reuniones científicas
SIN-1, A GRAS PROTEIN THAT BINDS THE C SUBUNIT OF THE NF-Y TRANSCRIPTION FACTOR, IS REQUIRED FOR PROPER NODULE DEVELOPMENT IN COMMON BEAN
CAROLINA RIPODAS ; MARINA BATTAGLIA ; JOAQUÍN CLUA ; MAEL BAUDIN ; MARIO O. AGUILAR ; ANDREAS NIEBEL ; MARÍA E. ZANETTI ; FLAVIO A. BLANCO
Providence, Rhode Island
Congreso; Plant Biology 2013; 2013
The study of molecular mechanisms involved in the specific recognition of the more efficient strains of rhizobia is crucial to understand the efficiency of the symbiotic process. A C subunit of the heterotrimeric nuclear factor Y (NF-Y), which is required for nodule organogenesis and bacterial infection, was shown to play a role in the selection of Rhizobium etli strains that colonize nodules in Phaseolus vulgaris (common bean). To further characterize this signaling pathway, we identified a GRAS protein, called SIN-1, which interacts with NF-YC in the yeast two hybrid system. This interaction was confirmed in planta by bimolecular fluorescence complementation. Phylogenetic analysis indicated that SIN-1 belongs to the PAT1 subfamily of the GRAS transcription factors. qRT-PCR experiments revealed that Sin1 is expressed in leaf and stem, with higher accumulation levels in roots and 14 day-old nodules. Post-transcriptional gene silencing using RNAi specifically reduced Sin1 mRNA levels in 90%. The length of the lateral roots was affected by silencing of Sin1, indicating that the product of this gene could be involved in lateral root elongation. On the other hand, root architecture, density of lateral roots, as well as the length of root hairs, were not affected. Silencing of Sin1 also led to a marked reduction of the number and size of nodules formed upon inoculation with R. etli and affects the progression of the infection thread to the nodule primordia. These data suggest that Sin1 plays a role in nodule formation and development in P. vulgaris roots.