Ru Zhang,

PhD

Associate Member

It Started with a Tomato

For as long as Ru can remember, plants have been a source of joy.

She recalls golden fields of canola surrounding her hometown in China. As an undergraduate, she studied transgenic tomatoes and sought out opportunities to be in the greenhouse, “I loved the smell of tomatoes and all of the green colors. To me, taking care of my plants was like taking care of my babies.” Pursuing plant science quickly became a clear path for Ru: she could surround herself with plants while also making an impact on the future of our planet.

Swimming Photosynthesizers

Today, Ru’s lab studies green algae in order to understand how plants will respond to high temperatures. One of the plant processes that Ru’s lab focuses on is photosynthesis. Photosynthesis is how plants make food: they use sunlight to turn carbon dioxide into sugar that the cells can use as energy. It is also one of the most heat-sensitive biological processes. Her lab wants to understand how high temperatures affect photosynthesis, and which components of the photosynthetic process are most sensitive to it. If her lab’s research is successful, it would be possible to improve crops to have a greater yield potential even in a heating climate.

Land plants cannot move, but algae are the exception. Ru and her lab are currently using Chlamydomonas in their research, a type of alga that has two flagella, which are thread-like structures that allow them to swim. “They are actually very cute,” says Ru with a smile. These unicellular, swimming “photosynthesizers” serve as a great model organism to understand how photosynthetic cells respond to high temperatures.

Microscopic Organisms, Huge Solutions

With a growing population and a changing climate, Ru’s work has never been more important than it is today. “Climate change is increasing the frequency and duration of damaging heat to most crops. This will affect plant growth and development, including photosynthesis, ultimately reducing crop yield. We need to make crops more heat tolerant in order to feed people.”

By 2050, we will need to double the amount of food we currently produce in order to feed nearly 10 billion people. While daunting, contributing to the solution is what motivates Ru: “I love my job because I can use my research to help solve one of the most meaningful challenges we face on our planet.” While our planet faces immense challenges, researchers like Ru are making it their mission to create a better future.

On her passion for plant science

"I feel more myself when I’m around plants."

Ru has been ambitious from a young age

"In high school, I already knew I wanted to be a professor."

On her passion for plant science

"I feel more myself when I’m around plants."

Ru has been ambitious from a young age

"In high school, I already knew I wanted to be a professor."

Get in touch with Ru Zhang

Research Team
Research Summary

Ru’s areas of research include photosynthesis, heat stress in green algae and land plants. She studies how photosynthetic organisms, especially photosynthesis, respond to high temperatures in order to engineer more heat-resistant crops and algae for improved food and biofuel production.

Ru Zhang

Associate Member

Divya Kanna

Postdoctoral Associate

Judy Mitchell

Administrative Assistant

Dominique Pham

Laboratory Technician

Michelle Richards

Grant Specialist

Ru Zhang

Associate Member

Divya Kanna

Postdoctoral Associate

Judy Mitchell

Administrative Assistant

Dominique Pham

Laboratory Technician

Michelle Richards

Grant Specialist

The Zhang laboratory at the Donald Danforth Plant Science Center employs algal genomics and plant spectroscopy to study how photosynthetic organisms, especially photosynthesis, respond to high temperatures.

Global warming increases the frequency with which photosynthetic organisms are exposed to damaging high temperatures. Heat stress impairs plant growth and reduces crop yield. To engineer crops with higher thermo-tolerance, it is imperative to understand how photosynthetic cells sense and respond to high temperatures.

Photosynthesis uses sunlight energy to make food and is essential for agricultural production. However, photosynthesis is one of the most heat sensitive processes in plants.  To meet the increasing global food demand for the future, we need to increase agricultural yield by engineering more robust and more efficient photosynthesis that can adapt to high temperatures. To achieve this goal, it is crucial to understand how photosynthesis responds to high temperatures and what factors limit its adaptation.

The Zhang laboratory are working on two main research topics:

Interrogate the functional genomic landscape of heat sensing and regulation in photosynthetic cells by using the eukaryotic, unicellular green alga Chlamydomonas reinhardti.

Although heat responses in land plants have been studied for years, several major questions remain open, especially heat sensing and regulation. Despite some advances in understanding heat responses in land plants, studies of algal heat responses are largely limited. Algae have great potential to produce biofuels, but they frequently experience rapid and large temperature fluctuations in ponds or outdoor bioreactors that can severely impact algal growth and viability.

The eukaryotic, unicellular green alga Chlamydomonas reinhardtii is a great model to study how photosynthetic cells respond to high temperatures. A genome-saturating, indexed, mutant library of Chlamydomonas has been generated, facilitating both reverse and forward genetic screens under heat stress. Furthermore, a high-throughput and quantitative barcoding approach has been developed in Chlamydomonas, enabling tracking growth rates of individual mutants in pooled cultures and screening for heat-sensitive mutants at genome-wide scale.

By using these advanced tools and systems-wide omics studies in Chlamydomonas, we aim to understand how photosynthetic cells respond to high temperatures and identify a list of genes involved in heat sensing, regulation, and adaptation in photosynthetic cells. Novel genes identified in Chlamydomonas that have orthologs in land plants will be investigated to improve crop thermo-tolerance.

Investigate the effects of high temperatures on photosynthesis in C4 plants:

High temperature increases photorespiration and reduces the efficiency of photosynthesis in C3 plants (e.g. wheat, rice, which produce three-carbon compound during the first step of photosynthetic CO2 fixation, C3 photosynthesis) . C4 plants (e.g. maize and sorghum, which produce four-carbon compound during the first step of photosynthetic CO2 fixation, C4 photosynthesis) uses two cell-types to concentrate CO2 and is more efficient than C3 photosynthesis in hot and dry environments. It is estimated that if C4 photosynthesis could be functional in C3 rice, the rice yield would be increased by at least 50%. A crucial step toward engineering C4 rice is to understand how C4 photosynthesis is regulated, especially under abiotic stresses, e.g. high temperatures. The light reaction of C4 photosynthesis is essential yet under-explored. By using spectroscopic and other biochemical, genetic approaches, we aim to investigate how C4 photosynthesis (especially the light reaction) is regulated under high temperatures by using C4 model plants Setaria viridis and C4 crop maize.