Plants are not as static as you think. David Ehrhardt combines confocal microscopy with novel visualization methods to see the three-dimensional movement  within live plant cells to reveal the other-worldly cell choreography that makes up plant tissues. These methods allow his group to explore cell-signaling and cell-organizational events as they unfold.

These methods allow his lab to investigate plant cell development and structure and molecular genetics to understand the organization and dynamic behaviors of molecules and organelles. The group tackles how cells generate asymmetries and specific shapes. A current focus is how the cortical microtubule cytoskeleton— an interior scaffolding that directs construction of the cell’s walls and the growth of the plant—is organized and functions and how this guides patterns of cell growth and division. This scaffolding is crucial for supporting important plant functions such as photosynthesis, nutrient gathering, and reproduction.

Recently, his group provided surprising evidence on how this reorganization process works. The cytoskeleton undergirding in each cell includes an array of tubule-shaped protein fibers called microtubules. The evidence suggests that the direction of a light source influences a plant’s growth pattern.

Imaging data, combined with the results of genetic experiments, revealed a mechanism by which plants orient microtubule arrays. A protein called katanin drives this mechanism, which it achieves by redirecting microtubule growth in response to blue light. It does so by severing the microtubules where they intersect with each other, creating new ends that can regrow and themselves be severed, resulting in a rapid amplification of new microtubules lying in another, more desired, direction.

Ehrhardt  received his Sc. B. from Brown University and his Ph.D. from Stanford University, where he was also a postdoctoral fellow before coming to Carnegie as a staff member. For more see https://dpb.carnegiescience.edu/labs/ehrhardt-lab

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The photosynthetic alga Chlamydomonas. Purchased from Shutterstock.
May 6, 2022

Palo Alto, CA— A team led by current and former Carnegie plant biologists has undertaken the largest ever functional genomic study of a photosynthetic organism. Their work, published in Nature Genetics, could inform strategies for improving agricultural yields and mitigating climate change.

Photosynthesis is the biochemical process by which plants, algae, and certain bacteria are able to convert the Sun’s energy into chemical energy in the form of carbohydrates.

“It is the foundation upon which life as we know it is able to exist,” said Carnegie’s Arthur Grossman, a co-author on the paper. “It makes our atmosphere oxygen rich while

3D projection of an Arabidopsis root tip. Credit: Dave Ehrhardt
May 3, 2022

Palo Alto, CA— In many ways, plants form the cornerstone of our society. They are key to the health of many ecosystems, underpin our entire food chain, provide us with fuel and medicine, and mitigate the effects of carbon pollution in our atmosphere. Despite this, there is still so much about the basic biology of plants that is not understood.

This is why Carnegie’s Sue Rhee and Selena Rice, along with colleagues from Carnegie and 30 more institutions, are heading up the Plant Cell Atlas project. The initiative brought together more than 800 experts to develop a community resource that will comprehensively describe plant cell types, the molecules they manufacture

Algae growing in a body of water, purchased from Shutterstock.
April 27, 2022

Palo Alto, CA— Algae have a superpower that helps them grow quickly and efficiently. New work led by Carnegie’s Adrien Burlacot lays the groundwork for transferring this ability to agricultural crops, which could help feed more people and fight climate change. Their findings are published in Nature.

Plant cells, algae, and certain bacteria are capable of converting the Sun’s energy into chemical energy using a series of biochemical reactions called photosynthesis. This process made Earth’s atmosphere oxygen rich, allowing animal life to arise and thrive, and underpins our entire food chain.

Photosynthesis takes place in two stages. In the first,

Plant Physiology cover art
February 7, 2022

Palo Alto, CA— Plant science will be crucial for solving many of society’s most-pressing challenges—including climate change, food security, and sustainable energy—but what are the outstanding mysteries that plant researchers need to solve to pave the way for this progress?

A new special-focus issue of Plant Physiology edited by Carnegie’s Sue Rhee, Julia Bailey-Serres of UC Riverside, Kenneth Birnbaum of NYU, and Marisa Otegui of the University of Wisconsin-Madison offers an overview how one initiative—the Plant Cell Atlas—is approaching these fundamental research inquiries and advancing the field.

The project started as a

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Revolutionary progress in understanding plant biology is being driven through advances in DNA sequencing technology. Carnegie plant scientists have played a key role in the sequencing and genome annotation efforts of the model plant Arabidopsis thaliana and the soil alga Chlamydomonas reinhardtii. Now that many genomes from algae to mosses and trees are publicly available, this information can be mined using bioinformatics to build models to understand gene function and ultimately for designing plants for a wide spectrum of applications.

 Carnegie researchers have pioneered a genome-wide gene association network Aranet that can assign functions

Ana Bonaca is Staff Member at Carnegie Observatories. Her specialty is stellar dynamics and her research aims to uncover the structure and evolution of our galaxy, the Milky Way, especially the dark matter halo that surrounds it. In her research, she uses space- and ground-based telescopes to measure the motions of stars, and constructs numerical experiments to discover how dark matter affected them.

She arrived in September 2021 from Harvard University where she held a prestigious Institute for Theory and Computation Fellowship. 

Bonaca studies how the uneven pull of our galaxy’s gravity affects objects called globular clusters—spheres made up of a million

Peter Gao's research interests include planetary atmospheres; exoplanet characterization; planet formation and evolution; atmosphere-surface-interior interactions; astrobiology; habitability; biosignatures; numerical modeling.

His arrival in September 2021 continued Carnegie's longstanding tradition excellence in exoplanet discovery and research, which is crucial as the field prepares for an onslaught of new data about exoplanetary atmospheres when the next generation of telescopes come online.

Gao has been a part of several exploratory teams that investigated sulfuric acid clouds on Venus, methane on Mars, and the atmospheric hazes of Pluto. He also

Anne Pommier's research is dedicated to understanding how terrestrial planets work, especially the role of silicate and metallic melts in planetary interiors, from the scale of volcanic magma reservoirs to core-scale and planetary-scale processes.

She joined Carnegie in July 2021 from U.C. San Diego’s Scripps Institution of Oceanography, where she investigated the evolution and structure of planetary interiors, including our own Earth and its Moon, as well as Mars, Mercury, and the moon Ganymede.

Pommier’s experimental petrology and mineral physics work are an excellent addition to Carnegie’s longstanding leadership in lab-based mimicry of the

Johanna Teske became the first new staff member to join Carnegie’s newly named Earth and Planets Laboratory (EPL) in Washington, D.C., on September 1, 2020. She has been a NASA Hubble Fellow at the Carnegie Observatories in Pasadena, CA, since 2018. From 2014 to 2017 she was the Carnegie Origins Postdoctoral Fellow—a joint position between Carnegie’s Department of Terrestrial Magnetism (now part of EPL) and the Carnegie Observatories.

Teske is interested in the diversity in exoplanet compositions and the origins of that diversity. She uses observations to estimate exoplanet interior and atmospheric compositions, and the chemical environments of their formation