CEFOBI   05405
CENTRO DE ESTUDIOS FOTOSINTETICOS Y BIOQUIMICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
ANALYSIS OF THE REGULATION OF NEW PUTATIVE P1 TARGETS IN LEAVES OF HIGH ALTITUDE MAIZE LANDRACES UNDER UV-B CONDITIONS.
Autor/es:
JULIA EMILIANI; SEBASTIÁN P. RIUS; ERICH GROTEWOLD; PAULA CASATI
Lugar:
Puerto Madryn
Reunión:
Congreso; 46 Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2010
Institución organizadora:
Sociedad Argentina de Bioquímica y Biología Vegetal
Resumen:
P1 is
a R2R3-MYB transcription factor that regulates the accumulation of a specific
group of flavonoids in maize floral tissues; among them the flavones and phlobaphenes. At present, only a few genes that
encode for enzymes in the last steps of flavonoid biosynthesis have been
demonstrated to be P1 targets. Recently, RNA-Seq have identified 777 genes
significantly higher in
red maize pericarps expressing the P1-rr
allele, than in white P1-ww
pericarps. This list includes all known P1
regulated genes, as well as other new putative targets. In this list, a number of transcription
factors, enzymes of the cell wall biosynthesis and other pathways were
identified. In this work, we have analyzed the transcriptional regulation of
these genes by UV-B in leaf tissues of different maize high
altitude landraces that express different P1 alleles that are expressed
in leaves and are also UV-B regulated, and in a low
altitude line (W23 b, pl) as a control. Our results show an induction of
almost all the analyzed genes in the different lines by UV-B. Also, in the high
altitude landraces, some transcripts have already higher levels in the absence
of UV-B than in the W23 line (e.g. RHS1, PAL3, JAC1). In
conclusion, P1 is probably involved in an overall adaptive response to UV-B radiation
in maize leaves, regulating the expression different targets besides the well
characterized flavonoid pathway.