The role of plasmodesmata-localized proteins in plants

Plant cells are surrounded by a rigid cell wall, which provides a challenge for communication between adjacent cells. Plants have evolved specialized cell wall channels called plasmodesmata (PD), which allow passage of mobile signals, such as transcription factors (TFs), RNAs, and hormones. Preliminary research has revealed novel proteins of unknown molecular function, that localize very specifically to PD in the model plant Arabidopsis thaliana, and whose activity is essential for normal plant development. Furthermore, specific interactions between the studied proteins and members of various TF families have been identified, suggesting a regulatory relation between them. The main objective of this research project is to functionally characterize the identified PD- localized proteins with specific focus on determining molecular mechanisms underlying their interactions with TFs and possible effects of these interactions on the respective transcriptional responses. Selected interactions will be examined to decipher possible effects on the intercellular movement, stability, metal loading, DNA-binding, and transcriptional activity of the respective TFs. This research project presents a multidisciplinary approach combining molecular, biochemical, and genetic methods to explore biological function of as yet unstudied group of plant proteins. It will provide new insights into the molecular mechanisms underlying the role of the PD- localized proteins and address new aspects of posttranslational regulation of TFs in plants. This work will enhance our knowledge of PD-associated molecular processes and thereby significantly contribute to better understanding of plant growth and development.