"Plants perceive the presence of dense vegetation as a change in light quality, i.e., a reduced red to far-red (R:FR) ratio. The responses to shade are generally referred to as the shade avoidance syndrome (SAS), and involve various changes in growth and physiology intended to overgrow or survive neighboring plants. Molecularly, phytochrome photoreceptors rapidly modulate plant development modulating the expression of several dozens of genes likely instrumental for implementing SAS responses that are likely forming a transcriptional web in Arabidopsis. A few of these genes encode partially redundant positive and negative regulators. The high amount of putative regulators (e.g. PAR1 and HFR1) suggests that to understand the SAS it is crucial (i) to establish the functionality of these regulators and (ii) to understand how they are organized in this web of transcriptional interactions. Hence, a major objective of this project is to define the architecture of the SAS transcriptional network in which PAR1 and HFR1 participate and to find out whether they are working in the same or different regulatory modules. In addition, the molecular basis of the cross-talk between shade perception and endogenous age-dependent transcriptional networks, such as those controlling hormone signaling and/or other developmental responses has to be clarified. Specific objectives are: Identification of 1) PAR1 and 2) HFR1 interacting nuclear transcription factors and their respective networks, 3) direct target genes of PAR1 and HFR1 proteins, and 4) age- related differences in molecular control of the SAS. With respect to the IEF call, this project will provide advanced research training to the applicant C. Then, a plant ecophysiologist, willing to extend her previous expertise (plant ecophysiology) to future integrative research approaches (plant molecular biology and ecophysiology) to advance her career as an independent researcher through innovative plant research."