Devaki Bhaya wants to understand how environmental stressors, such as light, nutrients, and viral attacks are sensed by and affect photosynthetic microorganisms. She is also interested in understanding the mechanisms behind microorganism movements, and how individuals in groups communicate, evolve, share resources. To these ends, she focuses on one-celled, aquatic cyanobacteria, in the lab with model organisms and with organisms in naturally occurring communities.

 Phototaxis is the ability of organisms to move directionally in response to a light source.  Many cyanobacteria exhibit phototaxis, both towards and away from light. The ability to move into optimal light for photosynthesis is likely to be an advantage. Bhaya is  particularly interested in how cells perceive light of different wavelengths; the photoreceptors involved, and how the molecular signals are transmitted into actions.

Science knows almost nothing about how microbial worlds communicate, evolve, share resources, or interact with other organisms. Bhaya’s recent research on speciation and evolution of thermophilic cyanobacteria in the microbial mats of hot springs in Yellowstone National Park has set the stage for a move into challenging new territory. Using pioneering methods, her group compiled full genome sequences of two dominant cyanobacteria (Synechococcus sp.) and a green, non-sulfur photosynthetic bacterium Roseiflexus sp. Her work represents the first glimpse into the complexity of microbial population to reveal a complex, integrated regulatory network. For more information see, https://dpb.carnegiescience.edu/labs/bhaya-lab

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Botryococcus braunii by © Karl Bruun posted on the AlgaeBase website.
July 14, 2021

Palo Alto, CA—Carnegie’s Arthur Grossman and Stanford University’s Ellen Yeh were awarded a $900, 000 grant this spring from the university’s public-private partnership Strategic Energy Alliance to research the synthesis of biofuels from a species of green microalgae called Botryococcus braunii.

Scientists from a diversity of research areas, including plant and algal biologists, are all applying their expertise to mitigate the dire consequences of climate change. But many first-generation biofuels, which are produced from edible crops like corn, pose a threat to food security by competing for land and freshwater reserves. They also often rely on fertilizers

3D reconstruction of an Arabidopsis embryo courtesy George W. Bassel.
July 6, 2021

Palo Alto, CA—Dehydrated plant seeds can lay dormant for long periods—over 1,000 years in some species—before the availability of water can trigger germination. This protects the embryonic plant inside from a variety of environmental stresses until conditions are favorable for growth and survival. However, the mechanism by which the baby plant senses water and reactivates cellular activity has remained a mystery until now.

New work jointly led by Carnegie’s Yanniv Dorone and Sue Rhee and Stanford University’s Steven Boeynaems and Aaron Gitler discovered a protein that plays a critical “go, or no-go” role in this process—halting

Megan Ruffley
June 22, 2021

Palo Alto, CA—Carnegie’s Megan Ruffley was awarded a prestigious Plant Genome Postdoctoral Research Fellowship in Biology from the National Science Foundation to study the genetics underpinning a plant’s ability to adapt to a changing climate.

Plants are fundamental to life as we know it. They make Earth’s atmosphere oxygen rich and form the basis of our food chain. They provide useful materials from fabric to lumber to medicines. Plants also remove carbon dioxide from the atmosphere, taking up and sequestering about a quarter of the emissions released by human activity. All of this means that it is crucial to understand how plant life will respond to a

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

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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