INVESTIGADORES
ARIEL Federico Damian
congresos y reuniones científicas
Título:
Functional and biochemical characterization of the transcription factor MTHB1 from M. truncatula
Autor/es:
ARIEL, FD; DIET, A; GRUBER, V; FRUGIER, F; CHAN, RL; CRESPI, M
Lugar:
Carlos Paz
Reunión:
Congreso; XLIV Reunión anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2008
Institución organizadora:
SAIB
Resumen:
MTHB1 belongs to the HD-Zip family of transcription factors (TFs) from the model legume Medicago truncatula (MT). Its expression in roots increases in response to high NaCl concentrations. The full length cDNA of MTHB1 was isolated and the codified protein was expressed in bacteria. EMSAs revealed that MTHB1 recognises in vitro the sequence CAAT(N)ATTG with the highest affinity, as other characterised members of the HD-Zip I subfamily. This DNA core was used to identify direct target genes of this TF in alternative transcriptional approaches. The validation of this box as a functional cis-acting element in the promoter regions of putative target genes is being carried out. The MTHB1 expression pattern in separate tissues and organs from the whole plant was determined by quantitative RT-PCR, both in normal conditions and in response to alternative environmental factors. Besides, the promoter region of MTHB1 was also isolated and cloned in a binary vector fused to the reporter gene GUS. A detailed expression pattern was then unravelled in roots of MT composite plants.  MTHB1 overexpression in MT roots resulted in a phenotype distinguishable from the wild type. Further functional analyses are now being undertaken also with mthb1 TILLING mutants. The information obtained from the different approaches is helping to understand how this TF participates in root architecture determination.