CEFOBI   05405
CENTRO DE ESTUDIOS FOTOSINTETICOS Y BIOQUIMICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Regulation of ASF1 proteins by cell cycle progression and UV-B radiation in plants
Autor/es:
LUCIANA LARIO; ELENA RAMIREZ-PARRA; CRISANTO GUTIERREZ; CLAUDIA P. SPAMPINATO; PAULA CASATI
Reunión:
Congreso; XLVIII Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular; 2012
Resumen:
ASF1 is a key histone H3/H4 chaperone that participates in a variety of DNA and chromatin-related processes, including DNA repair, in which chromatin assembly and disassembly is of primary relevance. Information concerning the role of ASF1 proteins in post-UV response in higher plants is currently limited. An initial analysis of in vivo localization of ASF1A and ASF1B indicates that both proteins are mainly expressed in proliferative tissues. Analysis of promoter sequences identified ASF1A and ASF1B as targets of the E2F transcription factors. These observations were experimentally validated, in vitro and in vivo. These data suggest a regulation of ASF1A and ASF1B during cell cycle progression. In addition, we found that ASF1A and ASF1B are associated with the UV-B induced DNA damage response. Transcript levels of ASF1A and ASF1B were increased following a UV-B treatment and RNAi silenced plants of both genes showed increased sensitivity to UV-B compared to wild type plants. Finally, by coimmunoprecipitation analysis we found that ASF1, physically interacts with N- terminal acetylated histones H3 and H4, and with acetyltransferases of the HAM subfamily, which are known to be involved in cell cycle control and DNA repair, among other functions. Together, here we provide evidence that ASF1A and ASF1B are regulated by cell cycle progression and DNA repair after UV-B irradiation