Research

 

Overview

Photosynthesis provides fixed carbon and energy for nearly all life on Earth, yet we know very little about many key aspects of this fascinating process. The aim of our lab is to transform our fundamental understanding of photosynthesis by developing game-changing tools. In the long run, our work contributes to increasing crop yields and reducing the environmental impact of agriculture.

 
Projects
 

We are applying transformative approaches to address key systems-level questions about photosynthesis.

What is the full set of genes required for photosynthesis?

Which parts work together?

What do all the uncharacterized parts do?

Our lab studies photosynthesis in the green alga Chlamydomonas reinhardtii.

The green plant photosynthetic apparatus is highly conserved and thus can be studied in Chlamydomonas.

Chlamydomonas can grow as a haploid and in the absence of a functional photosynthetic apparatus, allowing rapid isolation of mutants of interest.

Its unicellular nature and short doubling time enable higher throughput experiments than alternative systems.

We are working to systematically identify and characterize components of the green algal carbon concentrating mechanism (CCM).

The Chlamydomonas CCM allows it to use CO2 much more efficiently than C3 crop plants (including wheat and rice).

If we understood how this CCM works, we could engineer it into crop plants to increase their growth rates and reduce their need for water and fertilizer.

We are working with our collaborators in the NSF project "Combining Algal and Plant Photosynthesis" to transfer these components into the model C3 plant Arabidopsis.

This microscopy image shows the localization of LCIB (a key component of the CCM) in green; and chlorophyll (highlighting the chloroplast) in magenta. CO2 is concentrated in the pyrenoid, the organelle surrounded by LCIB.

We are discovering and characterizing new genes with roles in algal lipid metabolism and its regulation.

Photosynthetic organisms have the potential to play an important role in the production of renewable fuels and high-value lipids. Yet, many key aspects of lipid metabolism remain poorly characterized. For example, fatty acids are made in the chloroplast, but we don't understand how they get out of the chloroplast and to the rest of the cell.

 

 

Tool development

New tools enable scientific breakthroughs. Tool development is a core element of our lab. Initially, we have focused on developing tools to enable high-throughput genotyping and phenotyping of mutants in the single-celled green alga Chlamydomonas. In our view, there is a burning need for a powerful single-celled model organism for plant functions. The dream is that if we could adapt high-throughput genetics tools from yeast to Chlamydomonas, we could characterize the functions of many conserved genes much more rapidly than we currently can with multi-cellular plant models.

By adapting a next-generation sequencing technology from bacteria, we have increased the pace at which mutated genes in Chlamydomonas can be identified by >1,000-fold.

We are generating a genome-wide collection of mutants with known mutation sites in Chlamydomonas.

This is the first such collection in any single-cell photosynthetic eukaryote.

Click here for the project page.

We are developing high-throughput tools for measuring various phenotypes in the mutants on a genome-wide scale.

We make extensive use of cutting-edge robotics to increase throughput.