Salk faculty Joseph Ecker, Margarita Behrens and colleagues analyzed over 100,000 mouse brain cells using a scientific technique that identifies a chemical pattern called methylation, which is one way cells control gene expression. The scientists then applied this technique to thousands of cells from 45 different regions of the mouse brain and identified 161 clusters of cell types, each distinguished by its pattern of methylation. The team also showed that the methylation patterns could be used to predict where in the brain any given cell came from—not just within broad regions but down to specific layers of cells within a region. This means that eventually drugs could be developed that act only on small groups of cells by targeting their unique epigenomics.
Charting the brain destinations of neurons
Professors Ecker, Callaway and colleagues studied the association between DNA methylation and neural connections. The team developed a new way of isolating cells that connect regions of the brain and used the approach on over 11,000 individual mouse neurons, all extending outward from the mouse cortex. The patterns of methylation in the cells, they discovered, correlated with cells’ destination patterns.
Subtle genetic changes may lead to ALS
Professor Samuel Pfaff, first author Neal Amin and colleagues found that disease-related genes often have different degrees to which they are turned on or off. With only an incremental biological change around a critical threshold, a person can go from having no symptoms to being very sick. Their findings have implications for studying and treating the underlying causes of amyotrophic lateral sclerosis (ALS) and other neurological and psychiatric disorders. The results could also be applicable to a wide range of diseases involving changes in gene expression levels, like cancer.
How the brain ignores distracting information to coordinate movements
As you read this article, touch receptors in your skin are sensing your environment. But, unless a stimulus is particularly unexpected or required to help you orient your own movements, your brain ignores many of these inputs. Now, Assistant Professor Eiman Azim, first author and Staff Researcher James Conner and colleagues have discovered how neurons in a small area of the mammalian brain help filter distracting or disruptive signals—specifically from the hands—to coordinate dexterous movements. Their results may hold lessons in how the brain filters other sensory information as well.
Researchers identify neurons involved in overdose deaths
It’s long been known that opioid overdose deaths are caused by disrupted breathing, but the actual mechanism by which these drugs suppress respiration was not understood. Now, a new study by Assistant Professor Sung Han, first author Shijia Liu and colleagues identified a group of neurons in the brainstem that plays a key role in this process. The findings show how triggering specific receptors in these neurons causes opioid-induced respiratory depression, or OIRD, the disrupted breathing that causes overdose deaths. It also shows how blocking these receptors can cause OIRD to be reversed.
- Joan and Irwin Jacobs — A perfect matchJoan and Irwin Jacobs donate $100 million, a transformative gift, helping to launch Salk’s five-year, $500M philanthropic and scientific Campaign for the Future.
- How computational biology is making us smarterThe Salk Institute is embracing the artificial intelligence revolution and inventing new ways to investigate life. Machine learning, deep learning and other AI techniques are being used to probe massive data sets, identify useful information and make accurate predictions.
- Dan Tierney – Biology Meets TechnologyDan Tierney is no stranger to big data. When Tierney founded a financial technology firm in the late 1990s, long before he joined the Salk Institute’s Board of Trustees, he was fascinated by emerging computational approaches that could crunch data and reveal hidden truths.
- Natalie Luhtala — Shaping pancreatic cancer research to have real world applicationsThis year, Staff Scientist Natalie Luhtala celebrates her 10-year work anniversary at the Institute. In her current role, she’s directing a project examining an elusive signaling pathway to identify new targets for treating pancreatic cancer.
- Laura Newman — From mitochondria to craft beer and backLaura Newman, a Salk postdoctoral researcher, fell in love with science in a lab in college and switched from a medical program to pursuing biochemistry and developmental biology. At Salk, her main focus is on how cells can recognize when they’re sick or damaged in order to activate the immune system for cell survival.