Analysis of potato transgenic lines containing the StCDPK3 promoter fused to the reporter gene GUS

GRANDELLIS CAROLINA; BIALER MAGALÍ; RITA M. ULLOA

Potrero de Funes, San Luis

Congreso; SAIB, XLVII Reunión Anual; 2011

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Ca2+ sensors function to regulate diverse downstream targets leading to a stimulus-appropriate shift in physiology or developmental patterning.Calcium dependent protein kinases (CDPKs) are important components in plant signaling, capable of directly transducing a signal via catalytic activity. In potato, StCDPK1 is expressed in tuberizing potato stolons and in sprouting tubers (Gargantini et al, 2009), while StCDPK2 is highly expressed in leaves and sprouts (Giammaria et al, 2010). In an attempt to study a third isoform and its expression pattern, transgenic lines were generated carrying the StCDPK3 promoter region fused to a GUS reporter gene. Fourteen shoots were obtained that were able to grow and root in kanamycin selection media. Four of them presented GUS activity in a fluorometric assay but only two stained positively for GUS. The expression pattern was analyzed using in vitro potato plants and minitubers. The promoter was active in leaves, roots, early stages of tuber formation, in minitubers eyes and in the tip of minituber sprouts during primordial leaf development. Our results show that StCDPK3 could play a role in underground tissues (roots) and in aerial photosynthetic tissues (leaves and shoots). The fact that the promoter is active in minitubers eyes and sprouts is indicative of a role in developmental stages, leading to plant growth and survival.