INGEBI   02650
INSTITUTO DE INVESTIGACIONES EN INGENIERIA GENETICA Y BIOLOGIA MOLECULAR "DR. HECTOR N TORRES"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Genomic and functional characterization of StCDPK1
Autor/es:
ULLOA RM; GARGANTINI P; GIAMMARIA V; GRANDELLIS C
Lugar:
New Hampshire
Reunión:
Conferencia; Plant Molecular Biology Gordon research Conference; 2008
Institución organizadora:
Gordon Research Conference
Resumen:
StCDPK1 is a calcium dependent protein kinase expressed in tuberizing potato stolons. StCDPK1 genomic sequence contains 7 exons and 6 introns, the gene structure is similar to Arabidopsis, rice and wheat CDPKs belonging to subgroup IIa. There is one copy of the gene per genome and it is located in the distal portion of chromosome 12. Specific antibodies against StCDPK1 detected the protein in the microsomal fraction of swelling stolons and revealed a positive signal in the periphery of periderm and parenchyma cells suggesting that in vivo this kinase is targeted to the plasma membrane. Sucrose (4-8%) increased StCDPK1 protein content in non-induced stolons, however the amount detected in swelling stolons was higher. Transgenic lines with reduced expression of StCDPK1 (b7) did not differ from controls when cultured under multiplication conditions, but when grown under tuber inducing conditions some significant differences were observed: the b7 line tuberized earlier than controls without the addition of CCC (GA inhibitor), developed more tubers than wild type plants in the presence of hormones that promote tuberization in potato (ABA and BAP) and was more insensitive to GA action (stolons were significantly shorter than those of control plants). StCDPK1 expression was induced by GA, ABA and BAP. We conclude that St1CDPK is a GA-signalling component and our results suggest that this kinase could be a converging point for the inhibitory and promoting signals that influence the onset of potato tuberization.