New evidences for differential roles of L10 ribosomal proteins from Arabidopsis thaliana

MA LORENA FALCONE FERREYRA; ROMINA CASADEVALL; MARIANELA LUCIANI D´OTTAVIO; ALEJANDRO PEZZA; PAULA CASATI

PLANT PHYSIOLOGY.

AMER SOC PLANT BIOLOGISTS

Lugar: Rockville; Año: 2013 p. 378 - 391

0032-0889

The ribosomal protein L10 (RPL10) is an integral component of the eukaryoticribosome large subunit. Besides being a constituent of ribosomes and participating inprotein translation, additional extra-ribosomal functions in the nucleus have beendescribed for RPL10 in different organisms. Previously, we demonstrated thatArabidopsis thaliana RPL10 genes are involved in development and translation underUV-B stress. In this work, transgenic plants expressing ProRPL10:GUS fusions show that,while AtRPL10A and AtRPL10B are expressed both in the female and male reproductiveorgans, AtRPL10C expression is only restricted to pollen grains. Moreover, thecharacterization of double rpl10 mutants indicates that the three AtRPL10 differentiallycontribute to the total RPL10 activity in the male gametophyte. All three AtRPL10proteins mainly accumulate in the cytosol but also in the nucleus suggesting extraribosomalfunctions. After a UV-B treatment, only AtRPL10B localization increases inthe nuclei. We also here demonstrate that the three AtRPL10 genes can complement ayeast RPL10 mutant. Finally, the involvement of RPL10B and RPL10C in UV-B responses was analyzed by 2D gels followed by mass spectrometry. Overall, our data provide new evidences about the non redundant roles of RPL10 proteins in Arabidopsis.