HHMI Names the 2024 Hanna Gray Fellows

The cohort includes early career scientists working in research areas ranging from treatment-resistant cancers to how animals evolved to live on land. The HHMI Hanna H. Gray Fellows Program provides each fellow with up to $1.5 million in support over the span of up to eight years. The cohort includes early career scientists working in research areas ranging from treatment-resistant cancers to how animals evolved to live on land. The HHMI Hanna H. Gray Fellows Program provides each fellow with up to $1.5 million in support over the span of up to eight years. Today, the Howard Hughes Medical Institute announced the selection of the newest Hanna Gray Fellows, a cohort of 25 outstanding early career scientists who have demonstrated a commitment to making foundational discoveries while building an inclusive culture in academic science. The Institute will invest up to $1.5 million in support for each fellow over the course of up to eight years, spanning postdoctoral training through transition to starting their independent lab as a faculty member. This support allows each fellow the freedom to pursue challenging scientific questions at the forefront of their fields. The newest cohort includes scientists working in research areas ranging from treatment-resistant cancers to sleep dysregulation to how animals evolved to live on land. Through their successful careers, Hanna Gray Fellows will move science forward and will recruit, mentor, and inspire the next generation of scientists from all backgrounds. “HHMI is committed to investing in scientists who dare to tackle some of the biggest challenges of our lifetime,” said HHMI Vice President and Chief Scientific Officer Leslie Vosshall. “Our Hanna Gray Fellows are not only exceptional scientists, but they are also leaders who have proven their dedication to creating a more inclusive future for science.” Since the program’s founding in 2016, HHMI has committed more than $190 million to the Hanna H. Gray Fellows Program by selecting over 140 fellows, more than 30 of whom are already running thriving, independent labs as faculty around the country. In addition to financial support, the newest cohort joins the vibrant, multi-generational HHMI community, where fellows learn with experts and each other how to build healthy research environments that are creative, bold, inclusive, and effective. The Hanna H. Gray Fellows Program is committed to supporting scientists from a broad range of backgrounds and geographies. This year’s newly announced fellows completed their academic training at a wide variety of institutions. Where the 2024 Hanna Gray Fellows Studied California Institute of Technology Claremont McKenna College Columbia University Cornell University Duke University Harvard University Hong Kong University of Science & Technology Icahn School of Medicine at Mount Sinai Massachusetts Institute of Technology Mayo Clinic Memorial Sloan Kettering Cancer Center Miami University Morehouse School of Medicine Pontificia Universidad Católica de Chile Savannah State University State University of New York at Oneonta The Rockefeller University The University of Texas at Dallas Truman State University University of California, Berkeley University of California, Davis University of California, San Diego University of California, San Francisco University of California, Santa Barbara University of Florida University of Kansas University of Maryland Baltimore County University of Minnesota, Duluth University of Pennsylvania University of Pittsburgh University of Puerto Rico-Mayagüez University of Washington University of Wisconsin–Madison Washington & Jefferson College Washington University in St. Louis Weill Cornell Medicine Yale University The program is named for Hanna Holborn Gray, former chair of the HHMI board of trustees and former president of the University of Chicago. During her tenure, the Institute made significant changes to its process for selecting the scientists in which it invests, opening its doors to an ever-increasing pool of applicants. A competition for the next group of Hanna Gray Fellows opens immediately. In 2025, the Institute will again select up to 25 fellows to be announced in early 2026. This competition is open to all eligible applicants and no nomination is required. Learn more about the Hanna H. Gray Fellows Program and this year’s open competition on the program page. During development, the gastrointestinal tract forms from three embryonic layers that become the epithelial lining, musculature, and enteric nervous system. Assembly of these layers is essential for secreting hormones, digesting food, and absorbing nutrients. To better understand how the stomach forms, Maple Adkins-Threats is using human stem cell cultures and bioengineered devices (organ-on-a-chip) to model and identify regulators of gastric tissue assembly and development. Insights from studying how the stomach forms may improve treatments for gastric disorders. Unlike folded proteins, intrinsically disordered proteins lack a well-defined three-dimensional structure. This makes them difficult to target for therapeutic intervention. Jhullian Alston wants to understand how these dynamic proteins interact with DNA and other proteins. He investigates their roles in transcriptional regulation and cancer using a combination of single-molecule techniques and computational biophysics. By understanding how function is encoded into disordered protein sequences, he seeks to develop new strategies to target previously undruggable proteins. Bacterial viruses, or phages, are intracellular parasites that rely on host metabolism to survive and propagate. Paige Arnold studies how phages hijack bacterial metabolic pathways to support their own dissemination and how bacteria, in turn, exploit phage dependence on host metabolism to avoid annihilation. Arnold hopes this work will uncover metabolic vulnerabilities in bacteria that can be targeted to defend against bacterial infection in mammalian cells. Amma Asare’s research focuses on understanding how ovarian cancer cells adapt to survive medical treatment, making each recurrence more challenging to manage. By using advanced deep DNA sequencing techniques to analyze individual cancer cells during therapy, her work aims to reveal the specific changes that enable these cells to resist treatment. Insights gained from this study could lead to innovative approaches to prevent the growth of cancer cells and improve treatment outcomes for patients with recurrent ovarian cancer. As the immune system’s first line of defense, macrophages demonstrate immense power within the immune response across many diseases, including cancer. However, macrophages can sometimes suppress the immune system, which often contributes to disease progression. Camillia Azimi’s research focuses on engineering novel chimeric antigen receptors (CARs) to reprogram macrophages at the disease site for targeted control of the disease. This work seeks to expand our understanding of macrophage signaling and to modulate macrophage behavior with an aim to develop new approaches in innate immunotherapy. Dysregulated sleep is a prevalent feature of substance use disorders and mood disorders, especially in women. However, the neural mechanisms involved in such emotional interactions with sleep/wake systems are understudied. Brittany Bush aims to discover how sexually dimorphic brain structures – like the extended amygdala and hypothalamus – are involved in sleep, stress, and reward behaviors. She plans to elucidate the basis of sex differences in the connection between sleep dysregulation, drug-seeking behaviors, and maladaptive stress responses. As the largest organ in the human body, the skin is critical for sustaining health and barrier defense. Jim Castellanos, an anesthesiologist and immunologist, seeks to understand how immune cells interact with the skin’s stem cells to promote healing and regeneration, microbiome balance, and epigenetic inflammatory memory. His research will reveal the molecular dynamics of human skin healing with the potential to discover novel biomarkers and therapeutics for critically ill burn patients. The genome is a battleground where different genes compete for inheritance. Selfish genes, in particular, manipulate the development of eggs and sperm to bias inheritance in their favor. This “cheating” causes conflicts within the genome. When unresolved, these conflicts can lead to fertility defects across a range of organisms, including humans. Peiwei Chen studies the evolution and mechanisms of genetic conflicts to provide generalizable insights into genome biology and reproduction. Over our lifetime we experience various pathogen infections. Cori Fain explores how the body’s past infections can alter the brain’s landscape and functionality, and potentially accelerate brain aging. She investigates how tissue-resident memory T cells accumulate in the brain and their role in the decline of the brain’s ability to generate new neurons. Through this research, she seeks to answer: Do immune responses age your brain, and must neuronal memory be traded for immune memory? Peripheral nerve injury triggers massive waves of cellular transformation needed to rebuild damaged neurons. Sasha Fulton is developing new gene therapy tools to study this mysterious process with unprecedented precision. She is using these tools to explore cellular regenerative mechanisms in rodents, including a species with extraordinary evolutionary adaptations for improved healing – the naked mole rat. Her goal is to define the regulatory drivers of nerve repair and develop new regenerative therapies for nerve damage. Riley Galton is studying diapause, a state of suspended animation that allows many vertebrates – from sharks to mammals – to pause embryonic development in response to environmental changes. By examining the molecular pathways involved, she seeks to understand how diapause functions, how it evolved, and how genomes adapt to changing environments. This research not only advances our understanding of vertebrate development and evolution, but also has important implications for conservation efforts and human reproductive medicine. Plants are remarkable chemists, creating a wide array of bioactive molecules for medicine, energy, and agriculture. Colin Kim is captivated by how plants have evolved complex metabolic pathways to produce these molecules with exceptional efficiency. His focus is on unraveling the organization of the biosynthesis of these molecules at the tissue, single-cell, and subcellular levels. By decoding the biological mechanisms underlying plant chemistry, Kim seeks to develop sustainable methods for producing and designing useful molecules inspired by nature. Grant King is interested in how novelty arises in the cell biology of eukaryotes. He studies a particular evolutionary innovation: the 2-micron plasmid in budding yeast, an extraordinarily stable extrachromosomal DNA element that has persisted in its hosts for millions of years. He investigates how yeast cells have evolved to accommodate, limit, and perhaps even benefit from this genomic passenger. His research will provide insight into the principles underpinning the development of new cellular features. We swim in a sea of bacteria and viruses. Most of these microbes are harmless, but some are pathogens that threaten our health. How can the innate immune system distinguish harmless microbes from dangerous pathogens? Grace Liu believes that the key is to catch pathogens red-handed as they manipulate host pathways for their own benefit. By uncovering new immune surveillance programs that sense pathogen activities, she will develop strategies to combat viral transmission and restrain autoimmunity. Gut-brain communication is essential for processes such as digestion, satiety, and nausea. Alejandro López-Cruz, a scientist and gastroenterology fellow, is using systems neuroscience approaches to study how nutritional and aversive signals from the gut and the rest of the body are detected in the brainstem to regulate feeding, gut motility, and nausea. A better understanding of the mechanisms that regulate these processes will ultimately lead to the development of targeted therapies for disorders such as obesity. Good treatments for chronic pain are lacking because initial research in animal models does not often translate to humans. To tackle this, Juliet Mwirigi studies the biology of chronic pain in both rodent and human sensory neurons, focusing on evolutionarily shared mechanisms to develop better treatments. Her research centers on membrane receptors, which control cell signaling and are key drug targets. Using advanced tools, she explores where these receptors are, how they work, and how they differ across species. Insects use a diverse array of taste receptors to make critical decisions about feeding, mating, and egg-laying. Julianne Peláez wants to understand how genetic diversity among insect taste receptors causes structural differences in these receptors that ultimately drive divergent behaviors within and across species. Combining gene-editing, electrophysiology, and structural biology, she hopes to gain insights into how taste receptors function more broadly across insects – from pollinating honeybees to disease-spreading mosquitoes. Evolutionary shifts during ancient water-to-land habitat transitions necessitated substantial remodeling of molecules, cells, and organs so animals could interact with vastly different environments. Loranzie Rogers is exploiting amphibian metamorphosis as a unique model to ask how animals reprogram basic molecular functions to move from living in water to land within a single lifetime. These studies will provide fundamental insights into how cellular systems are transformed to facilitate novel traits and behaviors. After humans and chimpanzees diverged from a common ancestor more than five million years ago, unique genetic changes shaped the human brain, enabling language, advanced cognition, and complex behaviors. Daniela Soto aims to uncover the genetic basis of human brain evolution by studying human-specific forms of messenger RNA – molecules that help convert genetic information into functional proteins – using emerging long-read sequencing technologies. Her research not only illuminates how our brain evolved but also provides insights into neuropsychiatric conditions unique to humans. Biomolecular condensates regulate autophagy, a cellular process that destroys unwanted components, by remodeling cell membranes to encapsulate damaged organelles and proteins for degradation. However, the mechanisms driving these condensate-membrane interactions are poorly understood. To address this, Alex Stevens is engineering synthetic biomolecular condensate tools to probe the physical principles underlying autophagy. By deepening our understanding, these tools will help open new avenues for therapeutic strategies targeting conditions that involve autophagy defects, including neurodegenerative diseases, cancers, and metabolic disorders. The mammalian retina converts light into visual information and sends it to higher brain centers. Whitney Stevens-Sostre investigates how distinct populations of voltage-gated ion channels – integral membrane proteins that detect changes in voltage and regulate the flow of ions – shape the stimulus responses, connectivity, and intrinsic excitability of retinal neurons. Using single-cell electrophysiology and high-resolution microscopy, she aims to uncover the functional roles of voltage-gated ion channels in regulating retinal responses to light cues at different developmental stages. Degenerative diseases of the retina lead to a permanent loss of visual function. Salamanders spontaneously regenerate functional retinal neurons after injury, but the genomic mechanisms that enable this regenerative ability remain elusive. Jared Tangeman is investigating retina regeneration in salamanders to identify the evolutionary innovations that control injury-induced neurogenesis. By applying these findings to the mammalian retina, he hopes to improve cell therapies designed to combat blindness. The outcome of infection with a certain pathogen can differ widely between people. Some people experience mild disease while others develop severe infections. Such outcomes of infection are determined by hard-to-predict interactions between the immune system and the pathogen. Tiffany Taylor is identifying the pathways by which the host and pathogen respond to each other and how those pathways shift throughout an infection. Understanding diversity in host-pathogen interactions can help to predict how people will respond to infection. The “resolution revolution” in structural biology has yielded unprecedented insights into the molecular mechanisms that enable protein function. Yet, these insights fall short of delivering a full understanding, as they lack the crucial context of the cellular environment. José Velilla is leveraging advances in the fields of electron microscopy and mass spectrometry to bridge the atomic and cellular scales in understanding G protein-coupled receptor signaling from unconventional cell locations. G protein-coupled receptors are critical to a variety of physiological processes, including sight, taste, blood pressure regulation, and glucose metabolism. The repeated colonization of land by marine animals is one of the most significant evolutionary events in the history of life on Earth. Yet sea-to-land transitions are rare and challenging, requiring major changes to nearly every facet of an animal’s biology. Using terrestrial crabs as a new model system, Victoria Watson-Zink explores the evolution of terrestriality, seeking to understand how specific genomic, physiological, and developmental changes may have enabled the evolution of terrestrial life. ### HHMI is a private biomedical research institution. 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.