INVESTIGADORES
CHAN Raquel Lia
congresos y reuniones científicas
Título:
INTERACTION OF THE PLANT HOMEODOMAIN PROTEIN WUSCHEL WITH DNA
Autor/es:
FEDERICO ARIEL; AGUSTIN ARCE; RAQUEL CHAN
Lugar:
Pinamar
Reunión:
Congreso; XLI Reunión de SAIB; 2005
Institución organizadora:
SAIB
Resumen:
  WUSCHEL is an Arabidopsis thaliana transcription factor containing a compact homeodomain (HD), giving its own name to the family that it belongs to. This HD presents extra amino acid residues in two sites of the molecule, which may result in an atypical structure and have unpredictable effects on the interaction with DNA. Wuschel has been characterized as a key regulator of meristem differentiation, and apparently plays a critic role in the maintenance of embryonic cell identity. In this study, the HD of Wuschel was expressed as a fusion with GST from Schistosoma japonicum and purified by affinity chromatography. The binding sequence, CTCAG, has been determined by selecting binding sites from random?sequence oligonucleotides through several rounds of binding and amplification (SELEX). In vitro DNA binding, followed by electrophoretic mobility shift assays, indicated that this HD has a higher affinity for the SELEX resulting sequence than for the TAAT core. TAAT was previously proposed to be the target sequence of Wuschel in the second intron of the floral homeotic gene AGAMOUS, by analogy with typical HD binding sequences. Nevertheless, the sequence bound in vitro with highest affinity (CTCAG) is also present in the same intronic region, suggesting that an alternative interaction is actually taking place in the transcriptional regulation of the gene AGAMOUS.