?After undergoing an extensive review process by Salk senior faculty, Non-Resident Fellows, and scientific leaders in their respective fields, Leanne Jones and Satchidananda Panda have been promoted to Associate Professor, and E.J. Chichilnisky, Andrew Dillin, Martin Hetzer, and Jan Karlseder to full Professor, the Salk Institute for Biological Studies announced today.
"Faculty are the intellectual capital of the Salk Institute and these young scientists have proven their extraordinary talent and creativity," said Salk President William R. Brody. "They are the heavy hitters among their peers, and their research efforts and dedication will have a profound impact on human health through scientific discovery and creative research. That's what really matters."
E.J. Chichilnisky, a member of the Systems Neurobiology Laboratory, is working on deciphering how the retina, the tissue lining the back of the eye, encodes visual information so the brain can use it to produce visual experience. Employing a microscopic electrode array to record the activity of retinal ganglion cells - each of which views the world only through a small, jagged window called a receptive field - he was able to show that receptive fields fit together like pieces of a puzzle, preventing blind spots and excessive overlap that could blur our perception of the world. Most recently, he was able to trace for the first time the neuronal circuitry that connects individual photoreceptors with retinal ganglion cells, shedding light on the neural code used by the retina to relay color information to the brain.
Andrew Dillin, a Howard Hughes Medical Institute Investigator and Director of the Glenn Center for Aging, uses the tiny roundworm Caenorhabditis elegans to study the genetic and molecular pathways that regulate aging and aging-related diseases. His lab discovered the mechanisms that clear away toxic proteins in young, healthy brains - mechanisms that, Dillin found, break down with age and lead to protein aggregate build-up, the hallmark of age-related neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's. Most recently, he identified a molecular switch flipped by hunger, which links caloric restriction and longevity and that could identify drug targets for patients with aging-related diseases such as type II diabetes or cancer.
Martin Hetzer, who like Dillin and Karlseder is a member of the Molecular and Cell Biology Laboratory, is interested in how the organization of the nucleus influences gene activity and how disruption of its three-dimensional architecture can cause developmental defects, cancer and aging. Work of the Hetzer lab has established nuclear pore proteins as a new class of gene regulators and showed that nuclear membrane integrity declines with age and during tumorigenesis. Nuclear membrane irregularities are a hallmark of many diseases, including cancer and neurodegenerative disorders, and thus his work is relevant for diverse aspects of human health.
Leanne Jones, a member of the Laboratory of Genetics, uses the fruit fly Drosophila melanogaster to establish paradigms for how stem cell behavior is controlled and how the relationship between stem cells and their environment changes during development, aging, and tumorigenesis. Using the fly intestine and testis as model systems, Jones discovered that during the aging process, the level of support from a stem cell's specialized environment, also known as the stem cell niche, drops off, diminishing stem cells' ability to self-renew and adequately maintain tissues. In a separate study, she also found that stem cells adjust their numbers depending on the availability of nutrients to coordinate tissue maintenance with environmental conditions.
Jan Karlseder studies how cells keep tabs on their telomeres - the protective ends of chromosomes - and prevent catastrophic meltdowns to gain a better understanding of the interrelationship of aging and cancer. For example, he found that the telomere dysfunction observed in cells from patients with the premature aging disease known as Werner Syndrome is a major cause of genomic instability and could explain the high incidence of cancer seen in this disease. In a finding with direct implications for the treatment of cancer, he discovered that telomeres, which commonly end in a string of DNA rich in the base guanine (G), can also terminate with a different motif, a strand abundant in the base cytosine (C).
Satchidananda Panda tries to understand how our brain clock keeps track of time in all seasons and time zones and tells our body when to sleep, when to wake up, and when to eat. His work focuses mostly on melanopsin, a photopigment he had discovered before he joined the Salk Institute. His research in the Laboratory of Regulatory Biology revealed that melanopsin not only reports the intensity of incoming light to the circadian clock but also to regular visual centers in the brain. In a different set of experiments, he discovered that the daily waxing and waning of thousands of genes in the liver - the body's metabolic clearinghouse - is mostly controlled by food intake and not by the body's circadian clock as conventional wisdom had it.