Skip to main content
HHMI announces the selection of 25 exceptional early career scientists as 2022 Hanna Gray Fellows. The 2023 Hanna H. Gray Fellows Program competition is now open for applications.
HHMI announces the selection of 25 exceptional early career scientists as 2022 Hanna Gray Fellows. The 2023 Hanna H. Gray Fellows Program competition is now open for applications.

Today, the Howard Hughes Medical Institute (HHMI) welcomes 25 new Hanna Gray Fellows, talented postdoctoral scientists who represent a promising and more diverse future for biomedical science. The fellows represent 17 institutions across the United States.

Through the Hanna H. Gray Fellows Program and related efforts, HHMI seeks to increase diversity in biomedical science by recruiting and retaining individuals from groups currently underrepresented in the life sciences and by creating inclusive environments in which all scientists can thrive.

“We’re so excited to welcome these outstanding scientists into our HHMI family,” said Vice President and Chief Scientific Officer Leslie Vosshall. “Our resources and our growing community position the Hanna Gray Fellows to make scientific breakthroughs and contribute to building a healthy research culture.”

To date, HHMI has committed more than $142 million to increasing academic faculty diversity through the Hanna H. Gray Fellows Program, which currently includes 86 fellows (71 postdocs and 15 early career faculty). That investment continues growing, with annual appointments of up to 25 fellows as part of HHMI’s broader commitment to advancing inclusionexternal link, opens in a new tab across key career stages in academic science.

“Today more than ever, HHMI is focused on sustaining diversity in science, in part by developing the infrastructure and environments we need,” said HHMI President Erin O’Shea. “For our Hanna Gray Fellows, that means access to customized professional development, culturally aware mentorship, and networking with their peers and HHMI’s broader community of scientists, across career stages. Our goal is to make a meaningful, long-term investment in these scientists and the HHMI environments they experience.”

Fellows will receive funding for their postdoctoral 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. In keeping with HHMI’s ethos of supporting “people, not projects,” fellows will have the freedom to follow their curiosity and study the scientific questions that matter most – changing direction as needed – for the duration of the award.

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

A competition for the next group of Hanna Gray Fellows opens immediately. In 2023, the Institute will again select up to 25 fellows. This grant competition is open to all eligible applicants, and no nomination is required. Applicants may obtain more information and eligibility requirements at The deadline for applications is December 7, 2022, at 3:00 p.m. (ET). The selection of fellows will be made by late June 2023.


HHMI is the largest private biomedical research institution in the nation. Our scientists make discoveries that advance human health and our fundamental understanding of biology. We also invest in transforming science education into a creative, inclusive endeavor that reflects the excitement of research. HHMI’s headquarters are located in Chevy Chase, Maryland, just outside Washington, DC. 


2022 Hanna Gray Fellows

Begüm Aydin, PhD

The Rockefeller University
Mentor: Daniel Mucida, PhD

Begüm Aydin wants to understand how the environment affects the nervous system. Focusing on the nervous system inside the gut, often called “the second brain,” she is investigating the effects of gut microbiota and immune cells on the development and maintenance of gut neurons. By pursuing how neurons develop and recover upon microbial insults and inflammation, Aydin hopes to provide insights into neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and Parkinson’s disease, where pathological inflammation causes neuronal damage.

Halleh B. Balch, PhD

Stanford University
Mentor: Jennifer Dionne, PhD

Halleh Balch is a physicist pioneering new technologies deployed on autonomous underwater vehicles (AUVs) to study oceanic microorganisms and their impact on climate and human health. By developing methods for use on board AUVs to measure metabolites and the genes that encode for them, Balch aims to link gene expression and metabolic function with environmental drivers like temperature, nutrients, and acidity. Balch hopes this work will uncover new catalysts, useful therapeutics, and pathways to greater climate resilience.

Alain Bonny, PhD

The Rockefeller University
Mentor: Elaine Fuchs, PhD

Alain Bonny is working toward understanding how diverse cell types within a tissue coordinate actions to carry out complex behaviors. This process is especially critical when the tissue undergoes an injury, where the inflammatory response must be coordinated with tissue repair in a timely manner. Bonny is adapting and developing new tools to probe how cells communicate and coordinate the transition between inflammation and tissue repair. Understanding this “molecular handoff” will shed light on conditions that emerge when these precise coordination mechanisms break down.

Anna Bowen, PhD

University of Washington
Mentor: Nicholas A. Steinmetz, PhD

Choices are shaped by more than just the outside world. Anna Bowen endeavors to understand how the brain uses signals from the body to add meaning to external information and build adaptive behaviors. Using widescale neural recordings and simultaneous physiological measurements, Bowen is mapping the neural networks and signaling underlying food value learning. She hopes her work will reveal how we learn to predict food’s effect on the body and guide development of therapies for metabolic disease.

Giancarlo Bruni, PhD

University of California, Los Angeles
Mentor: Leonid Kruglyak, PhD

Biological cells – from bacteria to those in our bodies – maintain a difference in voltage, called membrane potential, between their exterior and interior. Membrane potential can power molecular machines and transmit cellular signals. Giancarlo Bruni seeks to understand how evolution has shaped membrane potential within and across species, and how differences in membrane potential contribute to biological variation between individuals. This work will provide insights into the role played by membrane potential in health and disease.

Jasmin Camacho, PhD

Stowers Institute for Medical Research
Mentor: Nicolas Rohner, PhD

Bats are an extremely diverse and successful group of mammals. A trait that has evolved multiple times in bats is preference for a sugary nectar diet. Jasmin Camacho is studying wild bats using cutting-edge metabolomics to identify and map the metabolic mechanisms that protect against the damaging effects of sugar consumption. Camacho’s goal is to uncover the nectar adaptations that underlie how mammals thrive on increased sugar consumption, which could help efforts to fight metabolic diseases like diabetes.

Cagney Coomer, PhD

Dartmouth College
Mentor: Marnie E. Halpern, PhD

Neural circuits are the fundamental connections underlying all brain functions, from cognition to behavior. Understanding these complex pathways has important implications for neuroscience research and human neurological disorders. Cagney Coomer is generating transgenic tools – which change an organism’s DNA – for transsynaptic tracing in zebrafish to map, monitor, and manipulate neural circuits. She aims to apply these powerful techniques to study both the developing and regenerating nervous system.

Andrea Cuentas-Condori, PhD

Yale University
Mentor: Daniel Colón-Ramos, PhD

Andrea Cuentas-Condori’s research aims to understand how some neurons communicate using two different neurotransmitters rather than one. Dual-transmission is a conserved capacity of neuronal circuits that scientists are just starting to understand at the cellular and circuit levels. Cuentas-Condori will use the compact nervous system of C. elegans to identify strategies that neurons use to organize different populations of synaptic vesicles along a single axon and how dual-transmitter signals integrate to modulate the behavior of a living animal.

Kiara Eldred, PhD

University of Washington
Mentor: Thomas A. Reh, PhD

Kiara Eldred wants to know how neuronal cell fates are specified during retinal development. Using retinal organoids – retinal tissue cultures derived from human stem cells – as a model system, Eldred seeks to understand the factors that help generate important cell types in the retina, as well as the factors that divert cells down an unplanned path toward tumorigenesis. Eldred believes that a better understanding of retinal development will allow her to regenerate retinal tissues lost in blinding diseases and understand the tipping points that drive tumorigenesis.

Lauren Hagler, PhD

Stanford University
Mentor: Dan Herschlag, PhD

RNA regulates gene expression by folding into complex structures and binding proteins. Lauren Hagler wants to predict how the structure of RNA inside a cell will affect downstream gene expression for any RNA sequence or mutation. Hagler’s research will bridge the gap between traditional biochemistry and high-throughput genomics to build a predictive model based on biophysical data. She hopes that this model will ultimately allow researchers to predict and modulate gene expression for therapeutic intervention.

Michelle Hays, PhD

Stanford University
Mentor: Gavin Sherlock, PhD

Parasites and their hosts shape one another’s evolution. In addition, the environment in which host-parasite conflicts take place can impact who wins and how. Michelle Hays is interested in how hosts evolve to fight back against parasites and the trade-offs associated with self-defense. Through experimental evolution of “killer yeast,” Hays is exploring how yeast’s natural parasites shape its evolution and give rise to biological novelty, while limiting host paths to adaptation.

Aaron Joiner, PhD

University of California, Berkeley
Mentor: James H. Hurley, PhD

Aaron Joiner is a firm believer that structure dictates function: from items that we can easily see and use (e.g., vehicles, furniture, tools) to cellular components that are challenging to visualize (e.g., DNA, RNA, proteins). In his research, Joiner determines the structures of proteins at the atomic scale, using cryogenic electron microscopy (cryo-EM). These structures then serve as the foundation for understanding the proteins’ cellular functions. He is particularly interested in a set of challenging proteins that dynamically interact with organelle membranes and is currently focused on the role of the C9orf72 protein in neurodegenerative disease.

Victor Lopez, PhD

The University of Texas Southwestern Medical Center
Mentors: Vincent S. Tagliabracci, PhD, and Joshua T. Mendell, MD, PhD

The advent of sequencing technologies has revealed a remarkable diversity among the protein families of most known species, yet many of these proteins remain uncharacterized. Victor Lopez is combining bioinformatics and biochemistry to identify and characterize new members of one of these families called the ATP-Grasp proteins. These proteins are responsible for many essential biological reactions and Lopez hopes that characterizing their biochemical function will help scientists understand their role in health and disease.

Johnathan Maza, PhD

University of California, San Francisco
Mentor: Jim Wells, PhD

Within our cells, proteins are routinely modified by post-translational modifications that grow the diversity and function of the approximately 20,000 proteins encoded by the human genome. Johnathan Maza is interested in developing new chemical biology tools to study poorly understood protein post-translational modifications. Maza hopes studying these modifications can shed new light on their role in biology and disease.

Margaret McDaniel, PhD

University of Washington
Mentor: Jakob von Moltke, PhD

Margaret McDaniel is working to understand how allergens and parasitic worms are sensed in the lungs and intestines. Even though allergens and parasitic worms don’t sound like they have much in common, they elicit a very similar immune response. By understanding the mechanisms by which these insults are sensed by different tissues, McDaniel hopes to uncover novel pathways that can be used to develop therapies for allergic disease or parasite infection.

Christopher Medina, PhD

Emory University
Mentor: Rafi Ahmed, PhD

Leveraging our immune system to fight tumors is becoming a frontline therapy for cancer treatments. Yet, in the battle against cancer, our immune cells can become exhausted and lose their tumor-killing potential. Christopher Medina’s research focuses on understanding the mechanisms of immune cell dysfunction at both a metabolic and protein level to help override this brake and reinvigorate the immune response.

Monique Mendes, PhD

Stanford University
Mentor: Mark J. Schnitzer, PhD

Monique Mendes is working to understand how astrocytes – specialized cells of the central nervous system – coordinate and respond to neuronal activity across brain states and behavior. Mendes wants to use novel imaging technology to simultaneously study the activity of neuronal populations and astrocytes in awake behaving mice. Identifying the mechanism that drives these interactions will answer fundamental questions about astrocyte physiology and the causal influence of astrocyte activity on neural circuits.

Gabriel Muhire Gihana, PhD

The University of Texas Southwestern Medical Center
Mentor: Gaudenz Danuser, PhD

Gabriel Muhire Gihana studies the role of cell morphology in regulating the molecular signaling of RAS, a prevalent human oncogene. Gihana seeks to understand how RAS-induced cell morphological changes contribute to the potential of RAS to cause cancer. Because direct inhibition of oncogenic RAS has proven very difficult, studying other cellular parameters that promote RAS cancer will likely lead to novel therapies.

Joshua Raji, PhD

The Johns Hopkins University
Mentor: Christopher John Potter, PhD

Mosquitoes transmit deadly diseases to humans around the world. The insects rely on their powerful sense of smell to detect humans, and Joshua Raji will exploit this to fight the bites. Raji plans to uncover the molecular targets that drive mosquitoes’ attraction to humans, and the human odors most crucial in activating these targets. Raji’s work could lead to novel ways of controlling mosquito behaviors, and ultimately protect humans from infectious bites.

Gabriel Romero, PhD

Harvard Medical School
Mentor: Lisa Goodrich, PhD

In response to stress, we adapt to avoid harm by enhancing the protective abilities and performance of key systems, including the auditory system, which must increase its sensitivity while also preventing itself from failing. By revealing the neural pathways and mechanisms underlying these responses, Gabriel Romero aims to determine how the brain communicates its internal state to the ear, enabling us to dynamically adjust how we detect and react to stimuli in the surrounding world.

Nicolle Rosa Mercado, PhD

The Johns Hopkins University
Mentor: Rachel Green, PhD

Cellular stresses, such as those caused by infection or chronic disease, trigger a general shutdown of protein synthesis. However, proteins that are important for cell recovery or activating programmed cell death continue to be produced. Nicolle Rosa Mercado studies how mRNA dynamics impact the regulation of protein production upon cellular stress. By identifying the targets and effectors of this regulation, Rosa Mercado’s work could reveal potential therapeutic targets to treat conditions ranging from neurodegeneration to cancer.

Maria Toro Moreno, PhD

Fred Hutchinson Cancer Center
Mentors: Harmit S. Malik, PhD, and Arvind Rasi Subramaniam, PhD

Our genomes encode thousands of microproteins with mysterious evolutionary origins and functions. Most research has focused on conserved microproteins, but this excludes rapidly evolving microproteins with potential roles in immunity. Maria Toro Moreno is investigating whether these rapidly evolving microproteins act as defenses against important pathogens such as HIV and influenza. Her research – combining creative evolutionary, high-throughput genomics, and virology approaches – will identify novel antiviral molecules encoded in our genomes and illuminate how they arise throughout evolution.

Ngoc-Han Tran, PhD

Whitehead Institute for Biomedical Research
Mentor: Ruth Lehmann, PhD

The continuity of life rests on faithful inheritance of both DNA and cellular machineries responsible for decoding the genomes. Ngoc-Han Tran studies the endoplasmic reticulum – a cellular compartment that varies in size and shape and performs a wide range of essential functions – throughout its dynamic partitioning in the ovary. By defining the relationship between endoplasmic reticulum shapes and functions during oogenesis, Tran seeks to understand how the endoplasmic reticulum is inherited across generations and how its malfunctions frequently lead to many diseases.

Jessica Warren, PhD

Arizona State University
Mentor: John McCutcheon, PhD

Plants are essential for life on Earth. One of the most important features of plant cells is the chloroplast, which originated from the capture of a cyanobacterium approximately a billion years ago and facilitates the process of photosynthesis. Jessica Warren is investigating how the chloroplast’s bacterial structures and genetic features have been integrated into modern plant cells, and how this incorporation controls plant development and physiology.

Shanice Webster, PhD

Duke University
Mentor: Sheng Yang He, PhD

Shanice Webster is examining tritrophic interactions among plants, pathogens, and the microbiome to uncover general principles and mechanistic underpinnings of how pathogens and the microbiome influence each other in plant pathogenesis. Understanding these interactions is critical to understanding disease at a holistic level. Given the importance of plant-microbe interactions to plant health and food security, Webster hopes that her study can lead to new insights and methods of disease interventions to improve global sustainability in the face of climate change.