The Cat Who Broke his Sweet Tooth

Carry the One Radio


Feb. 15, 2014 (Hosted by Sam Esselmann)


This is our first "CTOR Short"! Our producer Samantha explores why her cat Maverick cannot taste sweet foods.

Tapping into the Brain's Avoidance Centers: Garret Stuber

Traditionally, dopamine is known to transmit reward signals (food, sex, etc.) in the brain and promote behaviors that lead to that reward again. What you may not know, however, is that the area of the brain that releases dopamine, the ventral midbrain, also receives signals of aversion (things we find unpleasant or even dangerous) from a far-off brain region called the lateral habenula. These avoidance signals promote behaviors that lead us to avoid unpleasant or dangerous things in the world.

These brain circuits are necessary for survival and are the focus of Dr. Garret Stuber and his laboratory at the University of North Carolina - Chapel Hill. Using a tool known as optogenetics, Dr. Stuber can excite specific populations of neurons within mouse brains and observe their effects on behavior. For example, by stimulating the neurons in the lateral habenula that signal aversion, he can cause mice to avoid the location in which they received that stimulation. He is essentially creating an aversive stimulus by stimulating the neurons that would normally respond to harmful or unpleasant cues in the world. His work has important implications in addiction and psychiatric disorders

More on the Stuber Lab's research

Hosted by Osama Ahmed

Speaking with the Lizard Man: Eric Pianka

This month, in collaboration with the Age of Discovery podcast, we talk to Eric Pianka, an American ecologist known for his work on the community ecology of desert lizards and his classic textbook, Evolutionary Ecology. Dr. Pianka discusses how his interests in biology and reptiles were sparked in elementary school, and the experiences and relationships that have propelled his scientific career.

This program was hosted by Adrian Smith, an ant biologist at the University of Illinois. Adrian runs his own biology podcast called the Age of Discovery.

More on the Pianka Lab's research

Pulling DNA: Sophie Dumont

When a cell divides (called a parent cell), it provides complete copy of genes to each new cell that is formed (called daughter cells). This complicated process occurs repeatedly to accomplish an organism's development, repair, and replenishment. To reliably split the DNA correctly requires an orchestra of microscopic interactions among many molecules. While we know many of the molecules involved, scientists still know relatively little about the mechanical interactions that underlie this process. Our guest this month, Sophie Dumont, Assistant Professor in the Department of Cell and Tissue Biology at UCSF, hopes to understand these interactions. Specifically, her lab is working to understand how the chromosome (an organized structure of DNA) is divided and segregated into separate daughter cells. Her work has implications in various developmental disorders and cancer, which can result from errors in cell division. At the end of our talk she discusses the what it’s like to be a woman in science and gives advice to listeners interested in a career in science.

Music in this Episode: Lacrymae - Melodium, Bird’s Lament – Moon Dog, and Push and Pull – Rufus Thomas

More on the Dumont Lab's research

Hosted by Karuna Meda

Exploring the Zombie Brain: Brad Voytek

No, zombies are not real (at least not yet), but that does not mean we can’t enjoy analyzing their mental capacities. This is the work of Brad Voytek, scientist at UCSF and our guest this month on Carry the One Radio. When Brad isn’t busy with his scientific research mapping the prefrontal cortex, the part of the brain that makes us human, he “studies” the effects of zombification on the brain. He uses this work as a fun way to teach neuroscience. Listen as Brad describes the zombie brain and how it can help us teach how the human brain might work.

More on the Voytek Lab's research

Hosted by Sama Ahmed.

The big role of microRNAs in the immune system: Mark Ansel

The key to understanding our immune system might lie in understanding microRNAs. These are tiny strings of nucleotides (the same molecules that makes DNA) that influence how and which genes are expressed. This month we talk with Dr. Mark Ansel, an Assistant Professor in the UCSF Department of Microbiology & Immunology, about his work on these recently discovered molecules and their role in helping the body protect itself.

Within the cell, most RNA is produced from our DNA (genes) and translated to make proteins that help the cell function. microRNAs are produced from DNA but don’t make proteins. Instead, microRNAs ensure that the right genes are translated under the right conditions. microRNAs work in the immune system by helping a type of white blood cell, known as a T-cell, which regulate the production of antibodies that bind and destroy cellular invaders. The set of microRNAs that Dr. Ansel and his lab studies regulate genes that let T-cells recognize their environment and start the production of the correct antibodies. He has found that without these microRNAs, T-cells cannot properly mediate immunity. Dr. Ansel's work has important implications in understanding the immune system and what possibly goes wrong in diseases like HIV and AIDS. At the end of our interview, he talks about what motivates him most in science—the thrill of discovery.

Music: Kevin MacLeod: J. S. Bach: Prelude in C - BWV 846
More on the Ansel Lab's research
Hosted by Samantha Ancona Esselmann

How to become a heart cell: Benoit Bruneau

Gladstone Institute for Cardiovascular Disease

Sept. 1, 2013 (Hosted by Osama Ahmed)

Our bodies are made up of around 200 different cell types with very different structures and functions. Paradoxically, every cell contains the same genetic material. During development, proteins called transcription factors turn specific genes on and off. This can force a cell to develop into a brain cell rather than a skin cell, for example. But, when the right genes fail to turn on or when the wrong genes are expressed, developmental defects can occur.

Our guest this month, Dr. Benoit Bruneau, a Senior Investigator at the Gladstone Institute for Cardiovascular Disease, wants to know what makes a heart cell a heart cell. His lab is interested in how these different regulators interact, which factors are required for proper heart development, and which are altered in disease. This work answers important questions about how genes direct development, and it has potential applications for future therapies for heart disease.

More on the Bruneau Lab's research

The surprising health benefits of Botox (Part 2): Edwin Chapman

In the second part of our talk with Dr. Chapman, we discuss the positive effects that botulinum toxin A, otherwise known as Botox, can have in combating a number of medical conditions. You will be surprised by how often Botox is used for non-cosmetic procedures. It is prescribed for carpal tunnel syndrome, stuttering, excess sweating, cervical dystonia, and other debilitating conditions. Botulinum toxin A works by cleaving proteins important for cell communication (as discussed in Part 1), but exactly how it acts through the nervous system is unclear. Dr. Chapman’s lab has discovered that neurotoxins such as botulinum toxin A can be absorbed by neurons through vesicles at one end of the cell and be transported backward to the neurons connected to it on the other end of the cell, affecting specific proteins in long chains of cells. His research provides important insights into the mechanism of how this useful toxin works.

More on the Chapman Lab's research

Hosted by Sama Ahmed and Sam Ancona Esselmann

The cell's fusion machinery (Part 1) : Edwin Chapman

This month, in our first two-part episode, we talk about vesicle fusion with Dr. Edwin Chapman, a Howard Hughes investigator at the University of Wisconsin-Madison. Vesicles are small balloons within the cell that can carry a variety of material ranging from proteins to cellular waste. They are also important message-delivery machines that allow neurons to communicate with each other. Through an extremely fast and complicated process known as synaptic vesicle exocytosis, vesicles containing neurotransmitters fuse with the neuron's membrane, releasing packets of neurotransmitter that will bind to the receptors on a neighboring neuron. This process is the basis of nearly all neuron-to-neuron communication and, consequently, underlies our thoughts and behavior. Using different techniques, Dr. Chapman hopes to provide a better understanding of the structure, function, and dynamics of this poorly understood but fundamental process.

More on the Chapman Lab's research
More information on vesicle exocytosis

Producer: Osama Ahmed, Samantha Ancona Esselmann

Evolution of the deer mouse: Hopi Hoekstra

The way an organism looks and behaves is influenced by the genes it inherits. Through a process known as natural selection, genetic traits that are helpful for survival are passed to future generations, while traits that are less useful are selected out. For example, a fish that swims faster than another is more likely to escape from predators, reproduce, and pass down various inherited traits than its slower counterparts.

Hopi Hoekstra, a professor in the Department of Organismic and Evolutionary Biology at Harvard, and our guest this month on CTOR, is studying a longstanding question in biology: how do genes contribute to evolutionary adaptations? Listen as Dr. Hoekstra talks about how her lab uses the deer mouse to study the genetic basis of coat color, and burrowing behaviors. In addition, her research has important connections to human genetics and behavior. The genes her lab studies that determine pigmentation in the deer mouse are the same genes that determine hair color and skin cancer susceptibility in humans. And while humans obviously don’t burrow, the genes that affect burrowing and exploratory behaviors in the deer mouse could affect motivation and anxiety in humans. At the end of our talk, Dr. Hoekstra’s discusses her interest in political science before switching to a career in science.

This interview is part of an ongoing collaboration between Carry the One Radio and the Women in Life Sciences (WILS) group at UCSF.

More on the Hoekstra Lab's research

Women in Life Sciences (WILS)

Hosted by Karuna Meda

How the bat brain knows its place: Michael Yartsev

The ability of animals to navigate through the world is essential for survival and has been studied by scientists for over 40 years. Scientists have identified neurons called “place cells” that reside in a part of the brain called the hippocampus. Individual place cells are active only when the animal is in a particular location in space, and populations of place cells work together to create an internal representation of the environment.

Up until now, experiments involving the hippocampus and place cells have been conducted in two-dimensional settings, often with rats running through a flat maze. Our guest this month, Dr. Michael Yartsev, a fellow at The Princeton Neuroscience Institute and previously the Weizmann Institute, is interested in how the 3D world is perceived in the brain. He hopes to figure this out by recording activity from place cells in the brains of flying bats. Listen as Dr. Yartsev describes this unique system to study an old question.

Hosted by Osama Ahmed, Karuna Meda

Our protective microbiome: Susan Lynch

Believe it or not, we are made up of more microbes than human cells. In fact, for every human cell that makes up our body, there are nine times more bacteria, viruses, or fungi living on our skin, gut, or lungs. However, most of these microbes are not the kind that will make us sick. Most are harmless and, in some cases, even protective against diseases like Crohn’s disease and chronic sinusitis.
The function of many of these microbes is beginning to be understood by scientists like Dr. Susan Lynch, an associate professor of medicine at the University of California - San Francisco and our guest this month on Carry the One Radio. Listen as Dr. Lynch describes her work on the microbiome, how it develops, and its role in health and disease.

This episode is also part of our ongoing collaboration with our friends over at Youreka Science. They make science make sense, and they have covered one of Dr. Lynch's recent publications on the microbiome.

More on the Lynch Lab's research

An animated guide to some of Susan Lynch's work at Youreka Science

Hosted by Sama Ahmed

Exploring the Evolution and Development of the Vertebrate Skeleton: Rich Schneider

If you were asked to imagine how scientists study the way bones develop and grow, the last thing you might picture would be a quail-duck chimera. That is, unless you're Richard Schneider, associate professor in the department of orthopedic surgery at UCSF and our guest this month on Carry the One Radio.

Dr. Schneider and his lab have developed a system where stem cells from quail embryos are transplanted into duck embryos, and vice versa. The precursor cells from different species differ in growth speed and the structure of the bone they eventually create. His lab is interested in how these species-specific, developing cells interact with each other when they first meet. His findings may eventually lead to potential therapies for bone repair and regeneration.

More on the Schneider Lab's research

Host: Alex Mendelssohn

Neural circuits and motivational processes underlying hunger: Scott Sternson

This month on Carry the One Radio, we talk to Scott Sternson, a chemistry Ph.D-turned neuroscientist and scientist at Janelia Farms. Dr. Sternson is interested in what happens when we are hungry. He describes how a subset of neurons in a brain structure called the hypothalamus senses when the body is low on energy and motivates us to find food. By manipulating the electrical activity of specific neural populations and determining their effect on behavior, Dr. Sternson and his lab can map the function of the hypothalamus circuit. At the end of our talk, he discusses the importance of being self-critical of ones own ideas in science.

More on the Sternson Lab's research

Hosted by Karuna Meda

Towards personalized cancer treatments: Eric Collisson and Barry Taylor

This month on Carry the One Radio we talk with two scientists who are developing new strategies to treat cancer. Dr. Eric Collisson, a medical oncologist, and Dr. Barry Taylor, a computation biologist, have teamed up to identify and understand the complex signaling world that leads to cancer. Because of the complexity of these signaling pathways, two patients diagnosed with the same disease might need very different treatments. But by understanding the common pathways, Eric and Barry hope to eventually develop personalized therapies for cancer patients. Towards the end of our talk, they discuss the number one motivator for having a career in science.

More on the Collisson Lab's research More on the Taylor Lab's research

How does the brain motivate us to move?: Anatol Kreitzer

Our guest this month is Anatol Kreitzer, assistant professor of physiology and neurology at UCSF and a scientist at the UCSF-affiliated Gladstone Institutes. Dr. Kreitzer has made pioneering discoveries in the study of the neural circuits that control movement. His lab is interested in the function of the basal ganglia, a structure deep in the brain that controls movement, motivation, and action selection. Dysfunction of the basal ganglia can lead to movement disorders such as Parkinson’s disease and Huntington’s disease where patients have difficulty either initiating or controlling movements.

To understand how the basal ganglia works, the Kreitzer lab records electrical activity from neurons within the basal ganglia and determines how it relates to movement in behaving mice. They can also control this activity using an emerging technique known as optogenetics. By delivering genes coding for light-sensitive proteins into specific neurons, scientists in the lab can manipulate the electrical activity of certain neurons to see how movement is affected. This technique is being used to study the cells in the basal ganglia that guide our actions based on previous experience. Dr. Kreitzer’s work has provided significant insights into how the basal ganglia works and may eventually lead to potential cures for movement disorders.

More on the Kreitzer Lab's research

Hosted by Osama Ahmed

How the Brain Stays Stable in a Changing World: Graeme Davis

The human brain is the most complex structure in the body. It consists of about 100 billion neurons that make around 100 trillion synapses. These connections are constantly changing and the brain must maintain a stable level of electrical activity as it changes. If this balance is disrupted, conditions like epilepsy and schizophrenia can arise. How neurons achieve this feat is still a scientific mystery.

Our guest this month is Dr. Graeme Davis, professor in the department of biophysics at UC San Francisco. Dr. Davis hopes to solve the question of how the brain remains stable as it changes. His lab uses fly genetics to determine important genes involved in maintaining stable neural activity. Listen as Dr. Davis describes how one of these genes, dysbindin, is involved in stabilizing neural function and may have important implications in schizophrenia.

More on the Davis Lab's research.

Hosted by Sama Ahmed

Energy balance in a changing environment: Kaveh Ashrafi

The ability to maintain energy balance in a changing environment is essential for survival. The brain helps maintain this balance by sending signals that regulate food intake as well as fat storage. Abnormal metabolism has been associated with cardiovascular disease, type II diabetes, and even some neurodegenerative disease. However, the biology behind this link is not completely understood.

Our guest this month, Dr. Kaveh Ashrafi, an associate professor in the department of physiology at UCSF, hopes to tackle this important question. His lab uses microscopic nematodes to understand the genes and neural circuits that control fat and feeding regulation. By taking advantage of the simplicity of the nematode nervous system, scientists in Dr. Ashrafi’s lab can determine the precise role of these genes and how they control feeding behavior. His lab also studies how different chemicals in the environment can regulate metabolism and increase fat levels.

More on the Ashrafi Lab's research

Hosted by Karuna Meda

The neighborhood of cells in breast cancer: Zena Werb

University of California - San Francisco


Sept. 30, 2012 (Hosted by Karuna Meda)

Breast cancer affects one in eight women and is the seventh leading cause of death for women. Susceptibility to breast cancer is increased around the time of puberty when the breasts develop. More research into how the breasts normally develop and what causes normal cells to become cancer cells is still needed.

Our guest this month is Zena Werb, a professor of anatomy at the UCSF Family Comprehensive Cancer Center. Dr. Werb’s lab studies how a normal cell develops and the role of the cell’s “neighborhood”, the surrounding tissue that is necessary for support and proper development. Looking at how these cells interact in their microenvironment is important for understanding cancer metastasis and may potentially lead to treatments for this disease.

More on the Werb Lab's research

Treating Chagas' Disease: Jim McKerrow

Our guest this month is Dr. James McKerrow, a professor and chair in experimental pathology at UCSF. Dr. McKerrow and his team work to develop new drugs for neglected tropical diseases; diseases that affect low-income regions and consequently receive less attention from pharmaceutical companies. Dr. McKerrow takes us through the process of developing new treatments against these devastating infections.

More on the McKerrow Lab's research

Hosted by Alex Mendelsohn

How the brain responds to pheromones: Lisa Stowers

Our brains are responsible for helping us understand and move around in the world. What we perceive through our senses is transformed into electrical activity in our brains, and that activity determines how we act and respond to the environment. Yet, scientists are unclear about how brain cells carry out this transformation.

Our guest this month is Dr. Lisa Stowers from the Scripps Research Institute. Her lab uses mice to study how chemical signals known as pheromones activate particular groups of neurons, and how this activity produces instinctive behaviors of fear, attraction, and aggression. By studying this system, Dr. Stowers hopes to shed new light on how the brain processes senses and generates behavior.

More on the Stowers Lab's research

Producer: Sama Ahmed

The Social Worm: Cori Bargmann

What controls the way we behave? Our guest this week, Dr. Cornelia Bargmann, hopes to answer this complicated question. She explains how our biology, our genes, and the environment we live in can affect the way we behave. She is especially interested in understanding social behaviors, or how animals interact with each other. In her research, she uses the humble worm, known as c. elegans, to study the underlying biology that can switch an individual from being a loner to a party animal, and vice versa.

Cori is a professor at The Rockefeller University and an investigator of the Howard Hughes Medical Institute. She has recently been featured in the Charlie Rose Brain Series and The New York Times.

For an additional teaching resource, check out the lesson plan we created to accompany this episode.

More on the Bargmann Lab's research

Hosted by Osama Ahmed

Regenerating the heart: Deepak Srivastava

Heart disease is the number one cause of death in men and women, and congenital heart defects affect about 1 out of every 100 babies worldwide. Our guest, Dr. Deepak Srivastava, a professor of pediatrics and the director of the Gladstone Institute of Cardiovascular Disease at UCSF, is focused on changing that statistic.

By studying how stem cells in the developing embryo transform into heart cells, Dr. Srivastava hopes to find out what causes children to be born with heart abnormalities. Additionally, by understanding how nature develops healthy heart cells, research in the Srivastava lab may soon lead to new therapies for patients with heart disease. His lab has already found a way to guide non-muscle cells in the heart into fully functional, beating muscle cells in mice. He hopes to move these strategies into clinical human studies in the future.

At the end of our talk, Dr. Srivastava gives his most important advice for an aspiring, young scientist.

More on the Srivastava Lab's research
Hosted by Karuna Meda

Stem cells and epigenetics: Barbara Panning

The developing embryo is made up of special cells called stem cells. Unlike most cells, stem cells have the unique ability to transform into specialized adult cells, such as those that make up our heart or the neurons in our brain. In the last five years, scientists have designed a method to go backwards; now the specialized adult cells can be turned into embryonic stem cells. However, a lot of questions remain unanswered. For instance, scientists still do not completely understand what triggers stem cells to transform into different cell types. Or what process keeps stem cells from changing in the first place.
Our guest, Dr. Barbara Panning, a professor in the department of biochemistry at UCSF, is in the process of answering this question. Using a process called RNA interference, her lab turns off specific genes one by one to see how embryonic stem cells are affected. Her research has potentially important implications for diseases like breast cancer.

More on the Panning Lab's research

Hosted by Sama Ahmed

Mef2a and muscle regeneration: Christine Snyder

Even exercise can damage your muscles. Muscle cells then need to regenerate to keep you healthy. This month, we talk with Christine Snyder, a graduate student in the lab of Frank Naya at Boston University who studies how muscle regrowth is regulated.

Her work in the Naya lab focuses on a transcription factor (a protein that interacts with the DNA to affect gene transcription) known as Mef2A. Her lab studies mice that lack this transcription factor and show specific deficits in muscle development. She also explains how a technique called RNA interference can be used to silence certain genes to determine their function in cell cultures or animal models. Christine’s work has important implications for manipulating muscle regeneration after disease or injury.

More on the Naya Lab's research

Chronic pain is a disease: Allan Basbaum

Pain helps us avoid potentially harmful situations and is necessary for survival. While most of us only experience acute pain while the painful stimulus is present, some people unfortunately suffer from constant pain that persists long after the stimulus is removed. Our guest this week, Allan Basbaum, a professor and chair of the Department of Anatomy at UCSF, is interested in chronic pain and its cause.

During our interview, Dr. Basbaum explains how pain is in the brain; the pain that one person feels can be more (or less) intense than another person’s perception even if the stimulus is identical. His lab investigates how chronic pain can occur by changes in the nervous system and the role of epigenetics (the interactions between your DNA and all other non-DNA elements). They are also interested in transplanting inhibitory precursor cells (cells that develop and eventually inhibit the activity of surrounding neurons) to help the spinal cord suppress pain signals. His findings could eventually lead to effective therapies to treat this debilitating disease.

More on the Basbaum Lab's research

Hosted by Osama Ahmed

Makings of a memory: Loren Frank

The brain’s capacity to remember experiences to guide future decisions is an essential and fascinating ability. Our guest this month Loren Frank, an associate professor in the Keck Center for Integrative Neuroscience at UCSF, is working to understand this process.

Dr. Frank studies how the hippocampus, a brain structure required for the formation of memories, mediates spatial learning in rats. Within the hippocampus exist place cells: neurons that are activated whenever an animal is in a specific location in its environment. His lab records the neuronal activity of place cells during formation and “replay” of memories while rats explore their environment. Disrupting the “replay” prevents the long term formation of memory. Later in our interview, Dr. Frank discusses his initial interest in astrophysics and how he became interested in a career in neuroscience.

More on the Frank Lab's research

Mapping the brain's blood vessels: David Kleinfeld

David Kleinfeld is a professor in the Department of Physics at the University of California, San Diego. In this month’s episode, Dr. Kleinfeld talks about the different, important questions his lab is addressing.

One part of his lab is trying to understand how the brain uses sensory input to process information about the environment. The lab uses the vibrissa (whisker) system in rats and mice to understand how they sense and navigate the world. Next, Dr. Kleinfeld discusses how changes in blood flow in the brain can be used to visualize electrical activity evoked by different stimuli. The tools his lab let them see blood flow at the level of a single blood vessel. Using these optical techniques, they can map every blood vessel and brain cell within sensory cortex. Creating a complicated “road map” of the brain can eventually be used to help interpret results from imaging techniques such as fMRI used in humans.


More on the Kleinfeld Lab's research

Hosted by Osama Ahmed

How the Brain Maps What it Sees and Hears: Jason Triplett

Auditory and visual cues are crucial for perceiving the environment. Within the brain, both auditory stimuli and visual stimuli are organized topographically. In the visual system this means that neighboring spots on the retina project to neighboring spots in the brain. Likewise, areas along the basilar membrane in the cochlea which are sensitive to increasing frequencies of sound maintain this arrangement in the areas of the brain to which they project.

Our guest this week is Jason Triplett, a postdoctoral researcher at the University of California, Santa Cruz. He is interested in understanding the molecular and genetic mechanisms that guide the formation of these spatial maps. Jason will discuss how waves of neuronal activity that take place during development (before the eyes are even opened) are used by the brain to establish these complicated maps. Finally, we will hear briefly about the experiences that led him toward a career in science.

More on the Triplett Lab's research.

Hosted by Sama Ahmed.

Studying the retinal ganglion cells: Andrew Huberman

Our guest this month is Andrew Huberman, an assistant professor in the department of neurobiology at UCSD. Dr Huberman is interested in a classic question in development—how do the eyes connect to the brain? Cells known as retinal ganglia cells (RGCs) receive information from photoreceptors in the retina and carry this information to the brain. Connections from the left eye and right eye connect to the same part of the brain early on, but sort into two groups during maturation. Furthermore, different subtypes of RGCs respond to color, motion, and brightness and these subtypes target separate, designated regions of the brain. Andrew and his lab are exploring the mechanisms that guide the separation of different subtypes of RGCs during development. At the end of our interview, he explains the role of electrical activity and different genes in guiding the migration of these cells during development as well as how a course on the biology of behavior inspired him to pursue a career in neuroscience.

More on the Huberman Lab's research