Project Details
StPCP1: an IDD transcription factor involved in sugar-induced flowering and tuberization in Solanum tuberosum
Applicants
Privatdozentin Dr. Christina Kühn; Dr. Vanessa Wahl
Subject Area
Plant Breeding and Plant Pathology
Term
from 2014 to 2019
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 262540038
In potato plants (Solanum tuberosum) both flowering and tuberization employ similar inducing pathways. Since potato is cultivated for its underground storage organs, the time to tuberization and the tuber yield is of growing significance in terms of food security, which is why the identification of tuber inducing factors and mechanisms also affecting tuber quality traits is of broadest interest in plant research and agriculture. In this proposal we suggest the characterization of pathways affecting flowering and tuberization in potato within the framework of the priority program SPP1530. Flowering and tuberization are developmental processes that are regulated via multifactorial pathways. We are especially interested in understanding how these pathways converge with general metabolic processes in the plant. The POTATO COUCH POTATO1 (StPCP1) protein is a transcription factor of the IDD transcription factor family. StPCP1 RNAi plants show a flowering and tuberization phenotype. Preliminary quantitative real time PCR analyses suggest that StPCP1 is a general regulator of sugar transporters thereby influencing the carbohydrate status in potato plants. Several phloem mobile signals have been suggested to report of the sucrose status of source leaves to sink organs such as the shoot apical meristem or the stolon tips. We plan on investigating these putative phloem mobile factors in more detail, in particular trehalose 6-phosphate, miR156 and miR172 as well as their targets. Preliminary studies indicate that the sucrose content in the leaves is reflected by a changed expression and syntheses of these signaling components, as it has been shown for Arabidopsis. We further propose characterizing the nature of StPCP1 as a transcription factor as well as its downstream targets. This specifically involves the direct regulation of sucrose transporters (e.g. StSUT4) and the regulation of further downstream targets via the binding of the known ID1 domain. At the same time we will address open questions regarding the interaction with known signaling pathways leading to flowering and tuberization in potato, i.e. the photoperiod and the T6P pathways, as they have been shown to be affected by StPCP1.
DFG Programme
Priority Programmes