Plant Biochemistry & Physiology

BIOGRAPHY

Contact details:
Carnegie Institution
Plant Biology
260 Panama Street
Stanford CA 94305
Tel: 650 325 1521 x208
Fax: 650 325 6857
Email: wfrommer@stanford.edu

Research interests:
Transport processes are crucial for cell function. Moreover sensing mechanisms must exist at the plasma membrane to inform the cell about extracellular concentration and composition of solutes in order to be able to adapt transport capacities to the conditions.

Our research focuses on transport across the plasma membrane of plants. Using yeast suppression cloning systems we have been able to identify a large number of different transporters, including three different sucrose transporters, ammonium transporters, two superfamilies of amino acid transporters, two superfamilies of nucleobase transporters including transporters for cytokinins, oligo peptide transporters etc.

Functional studies (e.g. kinetic properties) in combination with localization studies and generation of knock out mutants help understanding the role of the individual proteins in the overall physiology of the plant.

We study the oligomerization of transporters using the split ubiquitin system, blue native electrophoresis and other methods to better understand posttranscriptional regulation.

We search for putative sensors at the plasma membrane that regulate transporter activity and turnover.

To be able to fully understand the transport processes it is crucial to determine the subcellular concentration of solutes, e.g. in the cell wall space versus the cytosol. Novel nanosensors have been developed that allow dynamic analysis of solute concentration in living cells using non-destructive methodology. These will in combination with the knowledge of transporter localization at the cellular and subcellular level provide new insights into the physiology of plants.

This technology also provides a new way of analyzing the physiology of other organisms including animals.