Analysis of rpl10 genes in Arabidopsis thaliana: Roles in development, translation, and UV-B response

MA LORENA FALCONE FERREYRA; ALEJANDRO PEZZA; PAULA CASATI

Tucumán

Congreso; XLV Reunión Annual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2009

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:21.0cm 841.95pt; margin:70.9pt 278.85pt 70.9pt 92.15pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> UV-B exposure was shown to increase expression of a number of maize ribosomal protein genes, including the single copy gene rpl10. The Arabidopsis genome contains three rpl10 genes encoding RPL10A-C. A. thalianaRPL10s are expressed with tissue and developmental stage specificity, showing high levels of expression in tissues with active cell division. RPL10C shows increased levels after UV-B, RPL10A expression is not UV-B regulated; and RPL10B is down-regulated by UV-B in all organs studied. Co-immunoprecipitation studies indicated that RPL10s in Arabidopsis associates with translation proteins, demonstrating it is a component of 80S ribosome; the presence of nuclear proteins suggest that at least one of the isoforms may have an extra-ribosomal role. Characterization of T-DNA insertional mutants indicates that rpl10 genes are not functionally equivalent. rpl10A and rpl10B mutant plants have developmental phenotypes: knockout rpl10A mutants are lethal, rpl10A heterozygous plants are particularly deficient in translation under UV-B conditions, and knockdown homozygous rpl10B mutants show abnormal growth. The results demonstrate rpl10 genes have different functions in A. thaliana, being involved in plant development, translation and UV-B response.