2010 |
Bautista, Diana Michele |
DP2Activity Code Description: To support highly innovative research projects by new investigators in all areas of biomedical and behavioral research. |
New Approaches to Identify Molecular Mechanisms of Touch and Pain in Mammals @ University of California Berkeley
DESCRIPTION (Provided by the applicant) Abstract: Mechanotransduction is the process by which mechanical energy is converted into electrical or biochemical signals. In mammals, mechanotransduction underlies a variety of senses, including hearing, touch and proprioception. Basic physiological processes, such as blood-pressure regulation and bladder function, also rely on mechanotransduction for normal homeostatic function. Despite its widespread importance, little is known about the molecular mechanisms underlying mechanotransduction in mammals. Do different cells use the same transduction molecules that are modified by cellular context? Or, are there multiple mechanotransducers that specialize in sensing different types of mechanical stimuli? The goal of his proposal is to identify molecules that mediate mechanotransduction in mammalian somatosensory neurons, the cells that convey our sense of touch and pain. While some candidate mechanotransducers have been identified, heterologous expression of these candidates has not yielded functional mechanosensitive channels, nor have gene knockout studies confirmed a role for any of these candidates in mammalian somatosensory mechanotransduction. My laboratory will undertake several unbiased approaches to identify new candidate mechanotransduction molecules. The specific aims of this proposal are to: (1) Identify components of the mechanotransduction machinery and (2) Examine the contribution of candidate molecules to somatosensation in vivo. These studies will provide novel insight into the molecular force transducers that underlie mammalian mechanotransduction. Public Health Relevance: Though unpleasant, pain warns us against harmful stimuli in the environment and evokes protective reflexes. But pain can also be a chronic, debilitating affliction that no longer serves a protective purpose. Chronic pain not only occurs after trauma-induced inflammation and tissue injury, but also results from many diseases;pain is the major complaint of patients suffering from cancer, AIDS, and diabetes. Understanding the mechanisms that evoke acute and chronic pain may lead to the development of much needed, new drugs and therapies to alleviate pain.
|
0.958 |
2011 — 2015 |
Bautista, Diana Michele |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Roles and Functions of Ion Channels That Mediate Mammalian Touch Transduction. @ University of California Berkeley
DESCRIPTION (provided by applicant): The mammalian somatosensory system detects a wide variety of mechanical stimuli, such as texture, shape, vibration or pressure. This variety of stimuli is matched by a diverse array of mechanosensitive somatosensory neurons. Non-neuronal cells in the skin, such as keratinocytes, may also coordinate with sensory neurons to transduce force. The goal of this proposal is to identify molecular and cellular mechanisms underlying somatosensory mechanotransduction. We hypothesize that both primary afferent somatosensory neurons and keratinocytes mediate mechanosensitive responses in the skin. We will use a variety of techniques including live-cell Ca2+ imaging, electrophysiology and pharmacology to characterize transduction channels in sensory neurons and keratinocytes. We will then probe the role of candidate channels in vivo. The proposed experiments will answer fundamental questions about somatosensory mechanotransduction, including: 1) What are the molecular identities of the ion channels that transduce touch in sensory neurons and keratinocytes? and 2) How does touch-evoked signaling in keratinocytes alter primary afferent neuron function? PUBLIC HEALTH RELEVANCE: Though unpleasant, pain warns us against harmful stimuli in the environment and evokes protective reflexes. But pain can also be a chronic, debilitating affliction that no longer serves a protective purpose. Chronic pain not only occurs after trauma-induced inflammation and tissue injury, but also results from many diseases;pain is the major complaint of patients suffering from cancer, AIDS, and diabetes. Understanding the mechanisms that evoke acute and chronic pain may lead to the development of much needed, novel drugs and therapies to alleviate pain.
|
0.958 |
2012 — 2017 |
Bautista, Diana Michele Brem, Rachel Beth [⬀] |
R21Activity Code Description: To encourage the development of new research activities in categorical program areas. (Support generally is restricted in level of support and in time.) R56Activity Code Description: To provide limited interim research support based on the merit of a pending R01 application while applicant gathers additional data to revise a new or competing renewal application. This grant will underwrite highly meritorious applications that if given the opportunity to revise their application could meet IC recommended standards and would be missed opportunities if not funded. Interim funded ends when the applicant succeeds in obtaining an R01 or other competing award built on the R56 grant. These awards are not renewable. |
Genetic Mapping of Novel Molecular Players in Itch @ University of California Berkeley
DESCRIPTION (provided by applicant): The somatosensory system mediates pruritus, or itch, the unpleasant sensation that evokes a desire to scratch. Acute pruritus serves an important protective function by warning against harmful agents in the environment such as insects, toxic plants or other irritants. Pruritus can also be a debilitating condition that accompanies numerous skin, systemic, and nervous system disorders. While many forms of itch are mediated by histamine signaling, recent work by us and others makes clear that additional key neural pathways are at play. Mast cells release a variety of puritogens that mediate allergy-evoked itch, psoriasis and eczema, and anti-histamines are not always effective in treating the full spectrum of allergic disorders. Likewise, most chronic itch conditions are insensitive to antihistamine treatment. For many itch disorders, therapeutic targets for treatment have yet to be identified. In light of the need for novel drug targets, the goal of this proposal is to identify genes and biomolecules that underlie itch, focusing on signaling mechanisms in primary afferent neurons and spinal cord modulatory interneurons. Somatosensory afferents are activated by itch-producing compounds that are released by a variety of cells in the skin. Pruritogens trigger somatosensory neuron activation by binding to G-protein coupled receptors and opening transduction channels that depolarize the nerve terminal and promote action potential firing; these neurons then signal to itch-specific neurons in the spinal cord. While recent studies have begun to delineate the basic characteristics of the itch circuit, the molecular mechanisms underlying itch have yet to be identified: the receptors, transduction channels and downstream signaling factors are largely unknown, in both primary afferents and spinal neurons. This grant proposal describes the development of new genetic approaches to meet this challenge. We are two biologists with experience and expertise in sensory neurobiology, genetics, and genomics who seek to identify the genes that drive itch behaviors. We will analyze the natural variation between genetically distinct mouse strains in itch-evoked behaviors and identify sequence and gene expression differences that underlie such phenotypic change. In contrast to traditional genetic screening approaches, which are not easily applicable to live-animal phenotypes in the mouse, the genetic mapping paradigm has the potential to survey a genome's worth of genetic perturbations and uncover novel determinants of itch. Identification of candidate itch factors will provide new targets for development of drugs and therapies to treat intractable itch. ! PUBLIC HEALTH RELEVANCE: Chronic itch results from of a number of skin diseases and systemic conditions, such as eczema, kidney failure, cirrhosis and some cancers. While itch from allergies or bug bites is readily treatable with anti-histamines, most forms of chronic itch are resistant to antihistamine treatment. Understanding the neural mechanisms that evoke acute and chronic itch may lead to the development of much needed, novel drugs and therapies.
|
0.958 |
2019 — 2021 |
Bautista, Diana Michele Parrish, Jay Z [⬀] |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Structural and Functional Coupling of Epidermis to Somatosensory Neurons in Drosophila @ University of Washington
Epidermal cells provide the first point of contact for sensory stimuli and are innervated by somatosensory neurons (SSNs) that shape our experience of the world. Both SSNs and epidermal cells are of great clinical relevance; SSNs are mediators of physiological and pathological pain, and some pathological skin conditions are associated with debilitating pain and itch. However, our understanding of roles that epidermal cells play in SSN development and function, particularly nociception, remain limited aside from a few well-studied examples. Characterizing these important intercellular interactions is complicated by the heterogeneity and complexity of vertebrate nervous systems. Drosophila provides an appealing system to close this gap in our knowledge, offering a wealth of genetic resources, ready imaging access of SSNs/epidermis with single cell resolution, a compact nervous system, and evolutionary conservation of key regulators of SSN development/function. In this project we will use an integrated approach to study an evolutionarily conserved intracellular interaction that involves the wrapping of SSN neurites by epidermal cells. The conservation of this intercellular interaction and the preferential ensheathment of nociceptors compared to other SSNs suggest that these sheaths may play key roles in development and function of nociceptive SSNs. Here, we test the hypothesis that epidermal ensheathment of SSNs functionally couples epidermal cells to SSNs. We will test this hypothesis using three lines of experimentation. First, we will characterize the response properties of Drosophila epidermal cells and identify epidermal sensory channels that mediate epidermal responses to noxious stimuli. Second, we will test requirements for sheaths in epidermal activation of nociceptors, define the neuronal substrates for epidermally-gated behavior responses, define the SSN repertoire functionally coupled to epidermal stimulation, and quantify contributions of epidermal activation to sensory-evoked behaviors. Third, we will identify signaling mechanisms linking epidermis and C4da neurons in the periphery and identify circuit- level effects of ensheathment. Given the enormous impact of pathological pain on quality of life ? chronic pain affects more Americans than diabetes, heart disease, and cancer combined ? understanding how epidermal cells modulate nociceptive SSN function is of great interest for development of novel therapeutics for pain management. Successful completion of this project will provide insight into a fundamental component of somatosensation that represents a novel control point for nociception that could define a new entry point for pain management.
|
0.913 |
2020 — 2021 |
Bautista, Diana Michele Brem, Rachel Beth [⬀] Ellerby, Lisa M Verdin, Eric M. (co-PI) [⬀] |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Genetic Dissection of Trait Variation Between Long-Diverged Mouse Species @ University of California Berkeley
PROJECT SUMMARY/ABSTRACT Over the four billion years that life has evolved on this planet, organisms have acquired amazing phenotypes. Some, like lions' manes and butterflies' wings, capture our attention by their sheer beauty. Others get us excited in a very different way?their relevance to biomedicine. Ecologists have catalogued remarkable disease and stress resistance traits in the plant and animal worlds, which have arisen to solve problems similar to those in human patients. We'd love to know the molecular basis of these natural resistance phenotypes, so that we can design drugs to mimic them in the biomedical context. However, most often, we know about a given trait because it is a defining feature of its respective species, acquired long ago to adapt to a unique niche. Now, millions of years later, the species usually has lost the ability to interbreed with relatives in other environments. And this reproductive isolation is a death knell for existing tools to map genotype to phenotype. The latter, which fill the pages of the modern genetics literature, rely on big panels of recombinant progeny from matings between distinct parents. These tools are no use in the study of species that can't mate to form progeny in the first place. We have developed a new strategy to break through this roadblock, and map the genetic basis of trait variation between long-diverged species. Our approach starts with a viable, but sterile, interspecific hybrid. In this hybrid, at a given gene, we introduce mutations to disrupt each of the two alleles in turn from the two species parents. These hemizygote mutants are identical with respect to background, except that at the target gene, each strain expresses a wild-type allele from only one of the parents. As such, if the hemizygotes differ with respect to a trait of interest, we infer that it must be because of functional allelic variation at the manipulated site. We have pioneered a genome-scale pipeline for this so-called reciprocal hemizygosity test, which we call RH-seq, using yeast as proof of concept. In the current proposal we describe experiments to port RH-seq to mammalian cells. We focus on a little-studied mouse species, M. castaneus, which can regrow axons of the central nervous system after injury. The genes we find in this pioneering study will serve as a springboard for drug design for stroke and brain trauma patients. And our metazoan RH-seq approach will pave the way for the genetic dissection of trait variation between species across Eukarya.
|
0.958 |