1. Characterization of Transcriptional Regulatory Networks controlling plant cell adaptation to environmental stresses

2. What is a Transcriptional Regulatory Network (TRN)? It’s a map of gene expression programs. These programs control plant development and plant adaptation to stresses. These programs depend on the recognition of specific promoter sequences by transcriptional regulatory proteins as well as epigenetic modifications of the genetic material.

3. Transcriptional Regulatory Networks Nuclear protein- protein interactions (selected TFs) Nuclear Protein-DNA interactions (selected TFs) Small RNAs Genomic DNA methylome (cytosine methylation pattern) The characterization of plant TRNs requires the qualitative and quantitative integration of inter-disciplinary biological approaches Transcriptome (RNA-sequencing) Hisotne modifications Bioinformatics

4. Rt=6t1+3t2+6t3+4t4+1t5 t1 t2 t3 t4 t5 t’1 t’2 t’3 t’4 t’5 Environmental stress Rt’=6t’1+3t’2+6t’3+4t’4+1t’5 A change between Rt and Rt’ might reflect: 1- a global change across all the different cell types of the analyzed tissue/organ t1≠t’1; t2 ≠ t’2; t3 ≠ t’3; t4 ≠ t’4; t5 ≠ t’5 2-a change of the transcriptome of a singe cell type. t1=t’1; t2 ≠ t’2; t3 = t’3; t4 = t’4; t5 = t’5 The cellular complexity of plant roots is not suitable to characterize TRNs.

5. David Ponder (SEM picture) A Single cell model is required to clearly characterize TRNs. Root hair cells are epidermal root cells characterized by their polar growth

6. Use of an aeroponic system to treat roots and investigate the biology and TRNs of the root hair cell