Sorting and Ubiquitylation Control of PIN2 Auxin Carrier in Arabidopsis
Abstract
Crosstalk between plants and their environment requires tight regulation of information exchange at the plasma membrane (PM). PM proteins mediate such communication, by sensing variations in nutrient availability, external growth determinants and pathogens as well as by controlled solute transport across the membrane border. PIN proteins are membrane proteins essential for inter- and intra-cellular distribution of the growth regulator auxin, influencing numerous aspects of plant development by orchestration of auxin distribution.PIN protein fate has been studied extensively, providing important insights into pathways, controlling plant membrane protein localization and intracellular sorting. Work in my lab focuses on analysis of PIN proteolytic degradation and its biological relevance. Experiments demonstrated that ubiquitylation functions as a signal for endocytic sorting of PIN2 auxin carrier protein, and that variations in PIN ubiquitylation are essential for dynamic adjustments in protein sorting to the vacuole, which in turn appears to modulate adaptive growth responses. However, we are still lacking detailed insights into mechanisms and pathways involved. Our earlier work resulted in identification of cis-acting elements and types of ubiquitylation that controlendocytic, degradative sorting of PIN2, and we now aim at the identification of trans-acting factors. By using PIN2 as model protein, we initiated forward and reverse genetic screens to characterize molecular determinants involved in sensing and controlling PIN2 ubiquitylation. We now aim at identification of pathways that mediate communication between plant cells and their environment via turnover of PM proteins, and will study its relevance for the adaptation potential of higher plants.
Publikationen
Project staff
Christian Luschnig
Assoc. Prof. Dr. Christian Luschnig
christian.luschnig@boku.ac.at
Tel: +43 1 47654-94230
Project Leader
08.07.2013 - 07.07.2018