Research Focus

All organisms depend on the supply with nutrients. However, the supply may change, thus the cells have to acclimate to changes in supply. To prevent damage by excess or due to starvation, homeostatic mechanisms have evolved.

The plasma membrane of a cell forms the boundary between a cell's contents and the outside of the cell. Proteins in the membrane are not only to protect the cell from its surrounding environment, such as biotic or abiotic stresses; but also, to control what enters and exits a cell, toxins and nutrients, etc. Transporters are thus located at key strategic positions and represent ideal control points. Our lab uses plants as a model system to focus on identifying key transporters for nitrogenous compounds and signaling molecules and to study fundamental biological processes such as nutrient uptake from soil and the distribution of nutrition throughout the organism. Major goals of the lab are:
 

• to identify missing components such as exporters, transporters for compartmentation and regulators novel transporters, and
• how transporters function,
• to identify the signaling networks controlling homeostasis.

Tool set we use and development

General standard tools in transporter studying, such as heterologous expression systems (e.g. yeast, Xenopus oocytes, plant protoplasts), isotopic substrate tracer uptake and efflux technology, electrophysiology, and the standard tool set of molecular, genetic, genome editing, and physiological to generate and analyze plant mutants defective in transport.

Genetically encoded fluorescent nano-biosensors
In addition, we developed tools for in vivo biochemistry, in particular genetically encoded fluorescent sensors for small molecules and fluorescent transporter activity reporters. We continue to optimize existing and develop new tools in this realm. We use advanced imaging technologies, such as light sheet microscopy, to quantify the sensor output and link the results to physiology. Sensors for nutrients like nitrate, second messengers such as calcium, or hormones allow the visualization of molecule dynamics in a living organism at high temporal and spatial resolution.

Open positions

Please contact Cheng-Hsun Ho for inquiries about open positions in the lab.