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