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

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Sue Rhee
November 10, 2022

Palo Alto, CA—Pioneering plant scientist Seung Yon “Sue” Rhee will retire from Carnegie next July to head up Michigan State University’s Plant Resilience Institute—an interdisciplinary effort designed to address environmental challenges by increasing the quality and productivity of food and biofuel crops through conducting basic plant science and training the next generation of leaders in the field.

Rhee has held a variety of positions at Carnegie since joining the Institution in 1999, including Acting Director of the Department of Plant Biology between 2016 and 2018. Over this 23-year period, she has overseen a number of cutting-edge research

November 4, 2022

Palo Alto, CA— We need to rethink how we think about Indigenous crops, say Carnegie plant biologists. These crops include groundnut, teff grass, and a wide range of cereals, grains, fruits, legumes, and root vegetables predominantly cultivated by small farms in Africa, Asia, and South America.

In a recent essay in Trends in Plant Science, Carnegie’s William Dwyer and Sue Rhee argue for the importance of anti-colonial language, as Western scientists develop an interest in regional crops that have been cultivated for generations by local farmers around the world. They were joined by collaborator Carol Ibe of the JR Biotek Foundation, a grassroots organization dedicated

An artist's conception courtesy of HOK.
October 3, 2022

Pasadena, CA—The state of California designated $20 million in its 2023 budget to help fund a new state-of-the-art Carnegie research facility in Pasadena where scientists will cross disciplinary boundaries to tackle the greatest climate challenges facing humanity today.  

Representing a proactive investment in the fight against climate change, the 135,000-square-foot structure is designed to house 200 new and relocated staff who will comprise Carnegie’s newly launched Division of Biosphere Sciences and Engineering. There, a diverse array of experts will draw on Carnegie’s long-standing expertise in exploring the natural world across scales to probe the

Artwork is courtesy of Mark Belan |
September 22, 2022

Palo Alto, CA—Climate change and habitat destruction may have already caused the loss of more than one-tenth of the world’s terrestrial genetic diversity, according to new research led by Carnegie’s Moises Exposito-Alonso and published in Science. This means that it may already be too late to meet the United Nations’ proposed target, announced last year, of protecting 90 percent of genetic diversity for every species by 2030, and that we have to act fast to prevent further losses.

Several hundred species of animals and plants have gone extinct in the industrialized age and human activity has impacted or shrunk half of Earth’s ecosystems, affecting

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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