THE EXPRESSION OF 14-3-3-ISOFORM IN POTATO IS DEVELOPMENTALLY-REGULATED

Recently, transgenic potato plants were created in which the 14-3-3 pr otein derived from Cucurbita was overexpressed. Derailed analysis of t hose plants suggested that a function of the isolated 14-3-3 isoform i s in the control of plant senescence. In this study a Cucurbita cDNA e ncoding a 14-3-3 protein was used to screen a potato leaf, root and gu ard cell cDNA libraries, and six: cDNAs encoding 14-3-3 isoforms were isolated. Western blot analysis revealed five 14-3-3 isoforms in potat o leaves, and the pattern of expression was dependent upon leaf maturi ty. The transgenic potato with repression of 14-3-3 protein (P14-3-3c isoform) synthesis shows a decrease in tuber number and an increase in tuber size. The antisense plants lose chlorophyll faster during their growth than the control plants.