Plant L10 Ribosomal Proteins Have Different Roles during Development and Translation under Ultraviolet-B Stress

MA LORENA FALCONE FERREYRA; ALEJANDRO PEZZA; JORDANE BIARC; ALMA L. BURLINGAME; PAULA CASATI

PLANT PHYSIOLOGY.

AMER SOC PLANT BIOLOGISTS

Año: 2010 vol. 153 p. 1878 - 1894

0032-0889

Ribosomal protein L10 (RPL10) proteins are ubiquitous in the plant kingdom. Arabidopsis (Arabidopsis thaliana) has threeRPL10 genes encoding RPL10A to RPL10C proteins, while two genes are present in the maize (Zea mays) genome (rpl10-1 andrpl10-2). Maize and Arabidopsis RPL10s are tissue-specific and developmentally regulated, showing high levels of expressionin tissues with active cell division. Coimmunoprecipitation experiments indicate that RPL10s in Arabidopsis associate withtranslation proteins, demonstrating that it is a component of the 80S ribosome. Previously, ultraviolet-B (UV-B) exposure wasshown to increase the expression of a number of maize ribosomal protein genes, including rpl10. In this work, we demonstratethat maize rpl10 genes are induced by UV-B while Arabidopsis RPL10s are differentially regulated by this radiation: RPL10A isnot UV-B regulated, RPL10B is down-regulated, while RPL10C is up-regulated by UV-B in all organs studied. Characterizationof Arabidopsis T-DNA insertional mutants indicates that RPL10 genes are not functionally equivalent. rpl10A and rpl10Bmutant plants show different phenotypes: knockout rpl10A mutants are lethal, rpl10A heterozygous plants are deficient intranslation under UV-B conditions, and knockdown homozygous rpl10B mutants show abnormal growth. Based on the resultsdescribed here, RPL10 genes are not redundant and participate in development and translation under UV-B stress.