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HHMI announces the selection of 21 exceptional early career scientists as 2020 Hanna Gray Fellows to support diversity in biomedical research. The 2022 Hanna H. Gray Fellows Program competition will open later this year.
HHMI announces the selection of 21 exceptional early career scientists as 2020 Hanna Gray Fellows to support diversity in biomedical research. The 2022 Hanna H. Gray Fellows Program competition will open later this year.

Twenty-one outstanding scientists. Eight years of financial support. One tight-knit community.

Today, the Howard Hughes Medical Institute (HHMI) announced the selection of the 2020 Hanna Gray Fellows, a cohort of 21 early career researchers who are taking on some of the biggest challenges in the life sciences, such as understanding the innerworkings of the brain or the complexities of the immune system. By unlocking basic principles, their work could one day ease symptoms in patients with chronic pain, treat kids suffering from pediatric leukemia, and spark new therapeutics for emerging infectious diseases.

“These promising researchers are poised to do groundbreaking work and ready to inspire the next generation of scientists,” says HHMI President Erin O’Shea. “HHMI is excited to welcome our new Hanna Gray Fellows into our community and to support them in their career journeys, as individuals and as a network of leaders changing the face of science.”

As of 2021, HHMI has committed more than $105 million to increasing academic faculty diversity through the Hanna H. Gray Fellows Program, which currently includes 64 fellows (61 postdocs and three early career faculty) and 62 faculty mentors. That investment continues to grow through regular competitions.

The new cohort of Hanna Gray Fellows represents 18 institutions across a broad swath of the United States, from California to Missouri and Michigan to New York. They join a growing community of Hanna Gray Fellows, all at a critical time in their academic careers ­– the postdoctoral training phase through the transition to becoming a principal investigator. Each fellow will receive up to $1.4 million over eight years.

The impact of becoming an HHMI Hanna Gray Fellow can be immediate, says 2018 Hanna Gray Fellow Melanie McReynolds, a biochemist at Princeton University: “This is a real commitment to each fellow and their science. People begin to take you seriously because they know HHMI has invested in you.”

In 2016, O’Shea, then HHMI’s chief scientific officer, spearheaded the Hanna H. Gray Fellow Program’s development. The program aims to increase diversity in science by recruiting early career scientists who represent a variety of racial, ethnic, gender, ability, and other underrepresented backgrounds.

In keeping with HHMI’s basic science mission, the program gives fellows the freedom to explore new scientific territory and follow their curiosity, seeking answers to challenging scientific questions. In addition, HHMI staff work to purposefully build a community that can provide professional development and interactive support. After becoming a fellow, “all of a sudden I had a community that looks like me and we’re all successful scientists,” says 2017 Hanna Gray Fellow Christopher Barnes, a structural biologist at the California Institute of Technology who will start his own lab at Stanford University in the fall.

Fellows can connect with each other and HHMI Investigators during annual science meetings and other events held by HHMI, though the COVID-19 pandemic has forced the program to get creative. Last summer, fellows attended a virtual mentor training workshop, and recently, a virtual seminar for one fellow’s practice job talk. That type of practice, along with advice from HHMI scientific officers on job opportunities, “is a major strength of the program,” says 2019 Hanna Gray Fellow Angela Phillips, an evolutionary biologist at Harvard University.

The COVID-19 pandemic delayed the selection of the 2020 cohort until December 2020. A competition for the 2022 cohort of Hanna Gray Fellows will open late this summer. McReynolds says she has already been speaking to interested grad students. “This is an opportunity of a lifetime that could set the trajectory of your career,” she tells them. “So what are you going to do about it?”

Meet the 2020 Hanna H. Gray Fellows



About the Hanna H. Gray Fellows Program

The Hanna H. Gray Fellows Program represents HHMI’s commitment to supporting talented early career scientists who have the potential to become leaders in academic research. By selecting individuals from groups underrepresented in the life sciences, HHMI seeks to increase diversity among academic faculty. Fellows’ successful careers will inspire future generations of scientists from the United States’ diverse talent pool.

The Hanna H. Gray Fellows Program is named for Hanna Holborn Gray, former chair of the HHMI trustees and former president of the University of Chicago. Under Gray’s leadership, HHMI developed initiatives that foster diversity in science education. HHMI continues to carry forward this work on college and university campuses across the US.

The Hanna Gray Fellows will:

Follow their curiosity

In keeping with HHMI’s long-standing approach to support “people, not projects,” fellows have the freedom to change their research focus and follow their curiosity for the duration of the award. The competition is open to researchers and physician-scientists dedicated to basic research in all the biomedical and life science disciplines.

Join a vibrant scientific community

The program provides opportunities for career development, including mentoring and networking with others in the HHMI scientific community. Fellows will also attend an HHMI Science meeting each year. This year’s 21 fellows join 43 current Hanna Gray Fellows selected in 2017, 2018, and 2019, during the program’s first three years.

Receive support during a critical career stage

Fellows will receive funding for their postdoc training and may continue to receive funding during their early career years as independent faculty. In total, fellows may receive up to $1.4 million each and be supported for up to eight years. Applicants may obtain more information and eligibility requirements at


The Howard Hughes Medical Institute plays an important role in advancing scientific research and education in the United States. Its scientists, located across the country and around the world, have made important discoveries that advance both human health and our fundamental understanding of biology. The Institute also aims to transform science education into a creative, interdisciplinary endeavor that reflects the excitement of real research. HHMI’s headquarters are located in Chevy Chase, Maryland, just outside Washington, DC.


2020 Hanna H. Gray Fellows and Mentors

Biafra Ahanonu, PhD

University of California, San Francisco
Mentor: Allan Basbaum, PhD

Biafra Ahanonu wants to understand the neural and molecular basis of pain, a complex experience that integrates sensory information with ongoing brain states. Ahanonu is pioneering methods to record spinal cord and brain neuron activity in active, non-anesthetized animals and identify pain-modulating proteins in neurons and synapses that process pain. Ahanonu hopes these findings will help the millions of Americans who suffer from chronic pain.

James R. Allen, PhD

Massachusetts General Hospital
Mentor: David Langenau, PhD

James Allen is working to understand how pediatric cancers, such as T-cell acute lymphoblastic leukemia, or T-ALL, co-opt our body’s mechanisms for their own ends. A major hurdle to developing a more effective treatment for T-ALL is a limited understanding of the genes and pathways that drive the cancer’s spread and are required for tumor growth. Allen plans to uncover novel drivers of the disease and identify pathways that can be targeted by therapeutics.

Nicolas Altemose, PhD, DPhil

University of California, Berkeley
Mentor: Gary Karpen, PhD

Nicolas Altemose is developing new technologies that use cutting-edge DNA sequencing machines to map protein-DNA interactions in uncharted regions of the human genome. Across the genome, thousands of proteins must interact with DNA to read, regulate, repair, and replicate it. Altemose hopes mapping those interactions can uncover the molecular foundations of various diseases.

Steve L. Bonilla, PhD

University of Colorado Anschutz Medical Campus
Mentor: Jeffrey Kieft, PhD

Steve Bonilla is using cryogenic electron microscopy, known as cryo-EM, to visualize diverse, dynamic, functional RNA structures. A major goal of biomedical research is to be able to predict how strands of functional RNA – strands that do not code for proteins – will fold into three-dimensional structures, but it is often difficult to visualize those structures due to their small size and dynamic, fluctuating nature. Cryo-EM may now allow researchers to do this. Bonilla plans to use his training in chemical engineering and computer science to help develop a system to predict RNA structure and function.

María Angélica Bravo Núñez, PhD

Harvard University
Mentor: Andrew Murray, PhD

María Angélica Bravo Núñez wants to understand the evolutionary role of aneuploidy, a state where cells have extra or too few chromosomes, which contributes to both cancer progression and drug resistance in fungal pathogens. Aneuploidy occurs when errors happen during the division of a cell’s nucleus. Bravo Núñez is investigating whether genes that play a role in creating sperm and egg cells, if turned on under the wrong conditions, can create aneuploid cells, and whether these cells may offer genetic advantages by increasing resistance to stressors.

Kyle Card, PhD

Cleveland Clinic Foundation
Mentor: Jacob Scott, MD, DPhil

So long as humans use antibiotics to fight bacteria, antibiotic resistance will be with us. Kyle Card is using bacteria from various stages of the seminal E. coli long-term evolution experiment (LTEE) – which has tracked bacterial evolution over more than 70,000 generations – to examine how bacteria’s evolutionary history, together with population size and mutation rates, contribute to the evolution of antibiotic resistance and associated fitness costs.

Ava Carter, PhD

Harvard Medical School
Mentor: Michael Greenberg, PhD

Ava Carter is working to understand how interpretation of sensory cues drives human brain development throughout childhood. Carter is studying a family of proteins called zinc finger transcription factors that are enriched during this process. By looking at the targets of these factors, Carter hopes to uncover how a relatively unexplored part of the genome might contribute to human brain development and evolution.

Willow Coyote-Maestas, PhD

University of California, San Francisco
Mentor: James Fraser, PhD

TrpV1 is the protein that sends signals of searing pain after a bite of a spicy chili pepper – but it also responds to scalding heat. Willow Coyote-Maestas is detailing the mechanisms by which this protein senses heat. Coyote-Maestas looks for genetic mutations that change TrpV1’s response to high temperatures, then uses high-resolution microscopes to examine how changes in temperature sensation alter protein structure. Linking TrpV1’s shape to its temperature sensitivity will help scientists better understand how we feel heat.

Morgan Gilman, PhD

Harvard Medical School
Mentor: Andrew Kruse, PhD

Morgan Gilman is scrutinizing a set of molecular mechanisms that nearly all bacteria use to build their cell walls – in order to help break them down. Several antibiotics, like penicillin, work by blocking the synthesis of peptidoglycan – a key component of bacterial cell walls – at specific stages of its assembly. However, many bacteria have developed resistance to these antibiotics. Gilman hopes to lay the groundwork for new antibiotics that target a family of proteins called the SEDS, which were recently discovered to play a critical role in a different stage of peptidoglycan synthesis.

Leah Guthrie, PhD

Stanford University
Mentor: Justin Sonnenburg, PhD

Leah Guthrie is mapping how gut microbes metabolize certain acids found in foods such as apples, pears, and artichokes. While these acids, known as hydroxycinnamic acids, are common in food, they accumulate at high levels in people with failing kidneys. By studying the byproducts produced when the acids are metabolized, Guthrie hopes to better understand their impact on the gut microbiome and their relationship to kidney disease.

Autumn Holmes, PhD

Washington University School of Medicine in St. Louis
Mentor: Michael S. Diamond, MD, PhD

Autumn Holmes is examining how chikungunya virus, which causes debilitating, often chronic arthritis in humans, enters cells and begins the infection process in mice. Like dengue and Zika viruses, chikungunya is transmitted through a mosquito species that, due to climate change and other factors, will likely be found in more parts of the world over the next several decades. Holmes hopes to understand how certain infected cells affect the progression of chikungunya disease and how the virus operates in the early stages of infection.

Kalli Kappel, PhD

Broad Institute of MIT and Harvard
Mentors: Aviv Regev, PhD, and Feng Zhang, PhD

Mutations to RNA sequences are responsible for dozens of human diseases. Kalli Kappel is investigating what makes these RNA sequences so toxic by examining the mechanism dictating where they reside in a cell, and how that relates to cellular function. Kappel hopes this work will inform future efforts to develop therapeutics for degenerative diseases.

David Martinez, PhD

The University of North Carolina at Chapel Hill
Mentor: Ralph Baric, PhD

David Martinez is examining the quirks of the human immune system that make our antibody responses to dengue virus infection so different from the defenses mounted against its cousins, which include Zika virus, yellow fever virus, and West Nile virus. When people infected with dengue virus later become infected with a second variant of the virus, they can experience severe, sometimes hemorrhagic reactions. Martinez ultimately wants to understand how the immune mechanisms causing these reactions can be exploited to prevent or cure viral disease.

Edgar Medina, PhD

University of Massachusetts Amherst
Mentor: Lillian Fritz-Laylin, PhD

Edgar Medina studies chytrids, one of the most ancient lineages of fungi, to explore the evolutionary pressures and adaptations that spurred the divergence of fungi and animals. Chytrids are unique among fungi because they share certain traits with animals that have been lost in other fungi over time, including cells that swim in a similar fashion to animal sperm cells. Medina hopes to uncover the molecular mechanisms underlying these traits in chytrids, which could aid efforts to fight fungal pathogens.

Evert Njomen, PhD

The Scripps Research Institute
Mentor: Benjamin F. Cravatt, PhD

Evert Njomen is using small molecule compounds known as chemical probes to identify specific proteins that could be used to develop treatments against a wide range of bacteria and viruses. The proteins Njomen studies are involved in recycling cellular waste and debris, a process known as autophagy, which also plays a central role in the immune system’s control of pathogens. Njomen hopes to develop advanced probes that can be used to ramp the autophagy process up or down for potential use in pharmaceuticals to target pathogens, including drug-resistant strains of bacteria.

Vanessa Puñal, PhD

University of Michigan
Mentor: Josie Clowney, PhD

Vanessa Puñal is examining the development of the brain circuits underlying sensory perception. Brains are wired to detect an ever-changing buffet of sounds, sights, and smells – and to tell them all apart. Like mixing primary colors to paint a rainbow, brain circuits can code for such a wide range of stimuli by mixing and matching inputs from a much smaller number of sensory receptors. In tracking how such a wiring pattern emerges in developing fruit fly brains, Puñal hopes to uncover insights about the organization of sensory perception more broadly.

Sofia Quinodoz, PhD

Princeton University
Mentor: Clifford Brangwynne, PhD

Sofia Quinodoz is unpacking the organization of cells’ nuclei. DNA condensed in the nucleus is strategically packed so that genes can be turned on and off at the right times. Scientists suspect that small droplets called nuclear condensates help guide this packing process, concentrating important proteins and making sure that related genes stick close together. As a doctoral student, Quinodoz developed a new way to map how the nucleus is organized. Now, Quinodoz is applying that technology to better understand how these droplets organize the genome and drive gene regulation.

Valeria M. Reyes Ruiz, PhD

Vanderbilt University Medical Center
Mentor: Eric P. Skaar, PhD

As antibiotic resistance becomes an increasingly urgent public health challenge, Valeria Reyes Ruiz is hunting for new ways to halt deadly Staphylococcus aureus bacterial infections. Her approach: depriving bacteria of the key nutrients they need to survive and spread in the body. Reyes Ruiz will detail how staph bacteria respond to the mineral manganese, and then work out the mechanisms by which immune cells starve bacteria of manganese to fight back. Understanding that interplay may help identify antibiotic-free ways to treat dangerous infections.

Marissa Scavuzzo, PhD

Case Western Reserve University
Mentor: Paul Tesar, PhD

Marissa Scavuzzo studies the nervous system – the one inside your gut. Using lab-grown organs to mimic the human intestine, Scavuzzo is mapping the diversity of support cells called glia. Glia in the brain regulate and protect neurons in many different ways, but their role in helping gut neurons work smoothly is a new field. Her goal: to understand the many functions of glia in a healthy gut, and then figure out how these cells respond to genetic, environmental, and dietary changes.

Zuri Sullivan, PhD

Harvard University
Mentor: Catherine Dulac, PhD

Sick animals often withdraw socially, hiding instead of seeking affection. Zuri Sullivan is hunting for the neural basis of those behavioral changes in the face of illness. Focusing on a recently identified brain circuit that influences whether mice crave social interaction, Sullivan is studying how inflammation affects the neural circuits that shape social behavior in mice. Untangling these interactions will help scientists better understand how the immune system affects behavior.

Guillaume Urtecho, PhD

Columbia University
Mentor: Harris Wang, PhD

Probiotics can populate the gut with a bevy of beneficial bacteria – but to be effective, those supplemental microbes need to stick around and multiply, not pass right through. Guillaume Urtecho is studying the genes that enable bacteria to set up shop in the gut. Urtecho plans to survey genetic variations in two different families of enzymes that bacteria use to shape their local environment to figure out which versions make the intestines a more habitable place for the helpful bacteria. The findings could guide the development of more effective probiotic therapies.