Matthew Evans wants to provide new tools for plant scientists to engineer better seeds for human needs. He focuses on one of the two phases to their life cycle. In the first phase, the sporophyte is the diploid generation—that is with two similar sets of chromosomes--that undergoes meiosis to produce cells called spores. Each spore divides forming a single set of chromosomes (haploid) --the gametophyte--which produces the sperm and egg cells.

Evans studies how the haploid genome is required for normal egg and sperm function. In flowering plants, the female gametophyte, called the embryo sac, consists of four cell types: the egg cell, the central cell, and two types of supporting cells. Two sperm cells from the male gametophyte—the pollen—fertilize the egg and central cells to produce the embryo and endosperm, respectively. The embryo and endosperm together make up the seed. The embryo develops into the new plant and the endosperm contains the nutritive material used by the embryo and seedling; it comprises the bulk of the grain weight in cereals such as wheat, rice, and maize.

Proper seed development depends on genes from the embryo and endosperm and from genes from the maternal embryo sac and sporophyte. Using maize, Evans is developing tools for identifying genes that are required for normal embryo sac development and function. He is also investigation the factors that prevent maize and it’s wild cousin teosinte from cross pollinating, and he is identifying  genes important for gametophyte function. For more see  https://dpb.carnegiescience.edu/labs/evans-lab

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Toxic "red tide" algal bloom. Image purchased from Shutterstock.
May 3, 2021

Palo Alto, CA—New work from a Stanford University-led team of researchers including Carnegie’s Arthur Grossman and Tingting Xiang unravels a longstanding mystery about the relationship between form and function in the genetic material of a diverse group of algae called dinoflagellates.

Their findings, published in Nature Genetics, have implications for understanding genomic organizational principles of all organisms.

Dinoflagellates include more than 2,000 species of marine and freshwater plankton, many of which are photosynthetic, and some of which also ingest other organisms for food. They play a wide variety of roles in various ecosystems, including extreme

Photo of flowering Arabidopsis thaliana purchased from Shutterstock.
February 11, 2021

Palo Alto, CA— Understanding how plants respond to stressful environmental conditions is crucial to developing effective strategies for protecting important agricultural crops from a changing climate. New research led by Carnegie’s Zhiyong Wang, Shouling Xu, and Yang Bi reveals an important process by which plants switch between amplified and dampened stress responses. Their work is published by Nature Communications.

To survive in a changing environment, plants must choose between different response strategies, which are based on both external environmental factors and internal nutritional and energy demands. For example, a plant might either delay or accelerate its

Figure from Energy and Environmental Science paper
February 1, 2021

Palo Alto, CA— What if we could increase a plant’s productivity by modifying the light to which it is exposed? This could increase the yield of important food and biofuel crops and also combat climate change by sequestering atmospheric carbon.

In a recent perspective piece in Energy and Environmental Science, Carnegie’s Arthur Grossman and Petra Redekop joined colleagues from Stanford University—Larissa Kunz, Matteo Cargnello, and Arun Majumdar—and University of Illinois Urbana Champaign’s Donald Ort to argue that specially engineered lighting modifications through the use of photoluminescent material could drive a next big leap in the green

Senna tora photo courtesy of Shutterstock.
November 24, 2020

Palo Alto, CA— Anthraquinones are a class of naturally occurring compounds prized for their medicinal properties, as well as for other applications, including ecologically friendly dyes. Despite wide interest, the mechanism by which plants produce them has remained shrouded in mystery until now.

New work from an international team of scientists including Carnegie’s Sue Rhee reveals a gene responsible for anthraquinone synthesis in plants.  Their findings could help scientists cultivate a plant-based mechanism for harvesting these useful compounds in bulk quantities.

“Senna tora is a legume with anthraquinone-based medicinal properties that have long

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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

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

Phillip Cleves’ Ph.D. research was on determining the genetic changes that drive morphological evolution. He used the emerging model organism, the stickleback fish, to map genetic changes that control skeletal evolution. Using new genetic mapping and reverse genetic tools developed during his Ph.D., Cleves identified regulatory changes in a protein called bone morphogenetic protein 6 that were responsible for an evolved increase in tooth number in stickleback. This work illustrated how molecular changes can generate morphological novelty in vertebrates.

Cleves returned to his passion for coral research in his postdoctoral work in John Pringles’ lab at Stanford

Brittany Belin joined the Department of Embryology staff in August 2020. Her Ph.D. research involved developing new tools for in vivo imaging of actin in cell nuclei. Actin is a major structural element in eukaryotic cells—cells with a nucleus and organelles —forming contractile polymers that drive muscle contraction, the migration of immune cells to  infection sites, and the movement of signals from one part of a cell to another. Using the tools developed in her Ph.D., Belin discovered a new role for actin in aiding the repair of DNA breaks in human cells caused by carcinogens, UV light, and other mutagens.

Belin changed course for her postdoctoral work, in

Evolutionary geneticist Moises Exposito-Alonso joined the Department of Plant Biology as a staff associate in September 2019. He investigates whether and how plants will evolve to keep pace with climate change by conducting large-scale ecological and genome sequencing experiments. He also develops computational methods to derive fundamental principles of evolution, such as how fast natural populations acquire new mutations and how past climates shaped continental-scale biodiversity patterns. His goal is to use these first principles and computational approaches to forecast evolutionary outcomes of populations under climate change to anticipate potential future