Salk Institute promotes five faculty members in genetics, structural biology, immunobiology, and neuroscience

April 28, 2023

Salk Institute promotes five faculty members in genetics, structural biology, immunobiology, and neuroscience

April 28, 2023

LA JOLLA—Five Salk Institute faculty members have been promoted for their notable, innovative contributions to science. These faculty members have demonstrated leadership in their disciplines, pushing the boundaries of basic scientific research. Assistant Professors Sung Han, Dmitry Lyumkis, and Graham McVicker were promoted to associate professors, and Associate Professors Sreekanth Chalasani and Ye Zheng were promoted to professors. The promotions were based on Salk faculty and nonresident fellow recommendations and approved by Salk’s president and Board of Trustees on April 21, 2023.

“Sung, Dmitry, Graham, Shrek, and Ye have all made significant advances in their respective fields, with discoveries that span a range of scientific disciplines and reflect the creativity that is central to Salk’s identity,” says Salk President Gerald Joyce. “We are eager to see what they accomplish next.”

Sung Han, holder of the Pioneer Fund Developmental Chair, works to understand how the brain recognizes environmental threats and sends signals that change physiology, metabolism, behavior, and emotion to avoid those threats. When this threat signaling pathway goes awry, it can create hypersensitivity, a characteristic of neuropsychiatric disorders, such as post-traumatic stress disorder (PTSD), as well as other panic and anxiety disorders. He recently uncovered a molecular pathway that initiates a fear response and described the connection between feelings of fear and breathing rhythm. Han also works to understand the science behind overdoses, which led to his discovery of a group of neurons that play a key role in the disrupted breathing that is often characteristic of overdose deaths.

Dmitry Lyumkis, holder of the Hearst Foundation Developmental Chair, investigates the mechanisms by which biological invaders (pathogens), like viruses, interplay with their hosts to establish and maintain infection. His lab uses multidisciplinary biophysical techniques centered around cryo-electron microscopy to understand how viral and host proteins assemble, interact, and produce diverse functional outcomes. Understanding the form and function of proteins helps unravel the complex roles they play in viral infections and in human diseases, such as cancer, and informs therapeutic strategies to target those diseases. He recently determined the molecular structure of HIV Pol, a protein that plays a key role in the late stages of HIV replication when the virus begins spreading throughout the body.

Graham McVicker, holder of the Frederick B. Rentschler Developmental Chair, studies how human genetic differences, known as genetic variants, affect traits and diseases. In the past decade, thousands of genetic variants have been associated with human diseases. However, the function of most of these variants is unknown and difficult to determine, since they are often in what are called “noncoding” portions of the human genome. Noncoding regions do not provide instructions for making proteins that enable cell function. Instead, research suggests they influence when and where (under which conditions and in which cell types) specific proteins are made by the “coding” portions of the genome. McVicker uses CRISPR and computational analysis to understand the function of each genetic variant in every cell type, with a particular focus on understanding cancer and diseases related to the immune system. His long-term goal is to reveal novel disease mechanisms that could support the development of personalized therapies. He was recently awarded a Curebound Discovery Grant and a Genomic Innovator Award.

Sreekanth Chalasani studies how animals make complex strategic decisions, such as balancing the quest for food with territorial defense and predator avoidance. His work has revealed the brain circuits that underlie these complex decisions. He also uses worm and mouse models to pinpoint the differences between healthy and dysfunctional brains, make inferences about the human brain, and shed light on conditions like autism spectrum disorder, post-traumatic stress disorder (PTSD), anxiety, and depression. He recently discovered how hunger signals in the gut communicate with the brain, and identified the cells and connections in the brain that facilitate decision making. Additionally, he engineered mammalian cells to be activated by sonogenetics, paving the way for other non-invasive versions of deep brain stimulation, pacemakers, and insulin pumps.

Ye Zheng studies the immune system dysfunction that causes inflammation and autoimmune disorders like rheumatoid arthritis, multiple sclerosis, type 1 diabetes, and asthma. Zheng focuses on regulatory T cells, which control immune responses and whose dysfunction has been linked to multiple autoimmune diseases. By looking at the genes that control regulatory T cells, he hopes to find new ways to manage T cell dysfunction and inspire future therapeutics. Recently, Zheng found a new target for alopecia treatment by discovering that regulatory T cells communicate with hair follicles to enable hair regeneration. Additionally, when looking at allergic skin inflammation in mice, he found that obesity changes the molecular underpinnings of allergic reactions—a finding that may have implications for allergies in humans, too.