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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December 14, 2016

Stanford, CA—Climate change and recent heat waves have put agricultural crops at risk, which means that understanding how plants respond to elevated temperatures is crucial for protecting our environment and food supply.

For many plants, even a small increase in average temperature can profoundly affect their growth and development. In the often-studied mustard plant called Arabidopsis, elevated temperatures cause the plants to grow longer stems and thinner leaves in order to cope with the heat stress.

New work led by Carnegie’s Zhiyong Wang uncovers the system by which plants regulate their response to heat differently between daytime and nighttime. It is published by

October 11, 2016

Stanford, CA—We generally think of inheritance as the genetic transfer from parent to offspring and that evolution moves toward greater complexity. But there are other ways that genes are transferred between organisms.

Sometimes a “host” organism can obtain genes from another organism that resides within its own cell (called an endosymbiont) through a process known as endosymbiotic gene transfer. At other times, an organism can obtain genes from a creature that lives in the surrounding environment, or from something that it eats, which is called horizontal gene transfer.

Furthermore, some levels of gene transfer can result in extensive loss of genes and genome reduction,

October 4, 2016

Stanford, CA— A feature thought to make plants sensitive to drought could actually hold the key to them coping with it better, according to new findings published by eLife, from Kathryn Barton of the Carnegie Institution for Science (Department of Plant Biology).

 Plants that are resistant to the hormone abscisic acid (ABA) have until now been understood to be bad at coping with drought. However, Barton and her team have now discovered ABA-resistant varieties that grow better than their normal neighbors when water is scarce. The new research suggests breeders should explore them for “stay green” traits.

 “When breeders are looking for plants able to withstand drought, they

September 22, 2016

Stanford, CA—The Howard Hughes Medical Institute (HHMI) and the Simons Foundation have awarded José Dinneny, of Carnegie’s Department of Plant Biology an HHMI-Simons Faculty Scholar grant. He is one of 84 scientists chosen out of some 1,400 applicants in a new program that the Howard Hughes Medical Institute (HHMI), the Simons Foundation, and the Bill & Melinda Gates Foundation have created. The grant will provide $250,000 per year for five years, in addition to overhead expenses, for an award total of $1,500,000.

The award will be funded by the Simons Foundation and administered by the Howard Hughes Medical Institute. Faculty Scholars are “early-career scientists who have

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Carnegie will receive Phase II funding through Grand Challenges Explorations, an initiative created by the Bill & Melinda Gates Foundation that enables individuals worldwide to test bold ideas to address persistent health and development challenges. Department of Plant Biology Director Wolf Frommer,  with a team of researchers from the International Rice Research Institute, Kansas State University, and Iowa State University, will continue to pursue an innovative global health research project, titled “Transformative Strategy for Controlling Rice Blight.”

Rice bacterial blight is one of the major challenges to food security, and this project aims to achieve broad, durable

Carnegie researchers recently constructed genetically encoded FRET sensors for a variety of important molecules such as glucose and glutamate. The centerpiece of these sensors is a recognition element derived from the superfamily of bacterial binding protiens called periplasmic binding protein (PBPs), proteins that are primary receptors for moving chemicals  for hundreds of different small molecules. PBPs are ideally suited for sensor construction. The scientists fusie individual PBPs with a pair of variants and produced a large set of sensors, e.g. for sugars like maltose, ribose and glucose or for the neurotransmitter glutamate. These sensors have been adopted for measurement of sugar

Fresh water constitutes less than 1% of the surface water on earth, yet the importance of this simple molecule to all life forms is immeasurable. Water represents the most vital reagent for chemical reactions occurring in a cell. In plants, water provides the structural support necessary for plant growth. It acts as the carrier for nutrients absorbed from the soil and transported to the shoot. It also provides the chemical components necessary to generate sugar and biomass from light and carbon dioxide during photosynthesis. While the importance of water to plants is clear, an understanding as to how plants perceive water is limited. Most studies have focused on environmental conditions

Today, humanity is increasingly aware of the impact it has on the environment and the difficulties caused when the environment impacts our communities. Environmental change can be particularly harsh when the plants we use for food, fuel, feed and fiber are affected by this change. High salinity is an agricultural contaminant of increasing significance. Not only does this limit the land available for use in agriculture, but in land that has been used for generations, the combination of irrigation and evaporation gradually leads to increasing soil salinity.

The Dinneny lab focuses on understanding how developmental processes such as cell-type specification regulate responses to

Peter van Keken studies the thermal and chemical evolution of the Earth. In particularly he looks at the causes and consequences of plate tectonics; element modeling of mantle convection,  and the dynamics of subduction zones--locations where one tectonic plate slides under another. He also studies mantle plumes; the integration of geodynamics with seismology; geochemistry and mineral physics. He uses parallel computing and scientific visualization in this work.

He received his BS and Ph D from the University of Utrecht in The Netherlands. Prior to joining Carnegie he was on the faculty of the University of Michigan.

Peter Driscoll studies the evolution of Earth’s core and magnetic field including magnetic pole reversal. Over the last 20 million or so years, the north and south magnetic poles on Earth have reversed about every 200,000, to 300,000 years and is now long overdue. He also investigates the Earth’s inner core structure; core-mantle coupling; tectonic-volatile cycling; orbital migration—how Earth’s orbit moves—and tidal dissipation—the dissipation of tidal forces between two closely orbiting bodies. He is also interested in planetary interiors, dynamos, upper planetary atmospheres and exoplanets—planets orbiting other stars. He uses large-scale numerical simulations in much of his research

Andrew Newman works in several areas in extragalactic astronomy, including the distribution of dark matter--the mysterious, invisible  matter that makes up most of the universe--on galaxies, the evolution of the structure and dynamics of massive early galaxies including dwarf galaxies, ellipticals and cluster. He uses tools such as gravitational lensing, stellar dynamics, and stellar population synthesis from data gathered from the Magellan, Keck, Palomar, and Hubble telescopes.

Newman received his AB in physics and mathematics from the Washington University in St. Louis, and his MS and Ph D in astrophysics from Caltech. Before becomming a staff astronomer in 2015, he was a

Gwen Rudie studies the chemical and physical properties of very distant, so-called  high-redshift galaxies and their surrounding circumgalactic medium. She is primarily an observational astronomer working on the analysis and interpretation of high-resolution spectroscopy of high-redshift Quasi Stellar Objects and low to medium-resolution near-infrared and optical spectroscopy of high-redshift galaxies. She is interested in understanding the intergalactic medium as a tool for understanding galaxy evolution and the physical properties of very distant galaxies such as the composition of stars and their star formation rates

Rudie received her AB from Dartmouth College and her Ph D