The goal of this proposal is to determine how 5HT3aR-expressing interneurons regulate the structure and function of layer 5 pyramidal neurons, the main output neurons in the cortex. 5HT3aR-expressing interneurons are abundant in superficial cortical layers and consist of several distinct cell types based on their unique electrophysiological properties, morphological features and expression of molecular markers. All 5HT3aR interneurons are strongly excited by serotonin acting on 5HT3a ionotropic receptors and ACh acting on nicotinic receptors. Our preliminary studies indicate that ablation or reducing the activity of a subtype of 5HT3aR interneurons increases the dynamics and density of dendritic spines on apical dendrites of layer 5 pyramidal cells in the living cortex. To determine how different subtypes of 5HT3aR interneurons, either individually or collectively, regulate pyramidal cells'structure and function, we will first determine which subcellular domains of pyramidal cells are innervated by individual subtypes of 5HT3aR interneurons and whether such synaptic contacts are stable over time. Furthermore, using optogenefic and genetic methods to silence or activate different types of 5HT3aR interneurons, we will determine which cell type(s) are responsible for modulating structural and functional properties of layer 5 pyramidal cells in vivo. In addition, we will determine the role of 5HT3aR interneurons in regulating learning-dependent structural remodeling of layer 5 pyramidal cells. Together, our studies will provide important insights into how these distinct groups of 5HT3aR expressing interneurons target specific domains of layer 5 pyramidal neurons to control their structural plasticity and excitability, thereby contnbufing to the development and function of cortical circuits. Because dysfunction of cortical inhibition is associated with epilepsy, anxiety, depression, autism and schizophrenia, our studies may lead to a better understanding of these neurological diseases and the development of new treatment strategies.

Public Health Relevance

GABAergic INs is critical for the normal and pathological function of the brain. This Program Project will investigate the roles of 5HT3aR INs, the least understood but largest population of GABAergic neurons in superficial cortical layers, on the development, function, and plasticity of the cerebral cortex. This component of the PPG will determine how 5HT3aR INs regulate the structure and function of layer 5 pyramidal neurons, the main output neurons in the cortex.

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Research Program Projects (P01)
Project #
Application #
Study Section
National Institute of Neurological Disorders and Stroke Initial Review Group (NSD)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
New York University
New York
United States
Zip Code
Nigro, Maximiliano José; Hashikawa-Yamasaki, Yoshiko; Rudy, Bernardo (2018) Diversity and Connectivity of Layer 5 Somatostatin-Expressing Interneurons in the Mouse Barrel Cortex. J Neurosci 38:1622-1633
Mayer, Christian; Hafemeister, Christoph; Bandler, Rachel C et al. (2018) Developmental diversification of cortical inhibitory interneurons. Nature 555:457-462
Priya, Rashi; Paredes, Mercedes Francisca; Karayannis, Theofanis et al. (2018) Activity Regulates Cell Death within Cortical Interneurons through a Calcineurin-Dependent Mechanism. Cell Rep 22:1695-1709
Godbole, Geeta; Shetty, Ashwin S; Roy, Achira et al. (2018) Hierarchical genetic interactions between FOXG1 and LHX2 regulate the formation of the cortical hem in the developing telencephalon. Development 145:
Bandler, Rachel C; Mayer, Christian; Fishell, Gord (2017) Cortical interneuron specification: the juncture of genes, time and geometry. Curr Opin Neurobiol 42:17-24
Leffler, Abba E; Kuryatov, Alexander; Zebroski, Henry A et al. (2017) Discovery of peptide ligands through docking and virtual screening at nicotinic acetylcholine receptor homology models. Proc Natl Acad Sci U S A 114:E8100-E8109
Wamsley, Brie; Fishell, Gord (2017) Genetic and activity-dependent mechanisms underlying interneuron diversity. Nat Rev Neurosci 18:299-309
Wilson, Daniel E; Smith, Gordon B; Jacob, Amanda L et al. (2017) GABAergic Neurons in Ferret Visual Cortex Participate in Functionally Specific Networks. Neuron 93:1058-1065.e4
Quattrocolo, Giulia; Fishell, Gord; Petros, Timothy J (2017) Heterotopic Transplantations Reveal Environmental Influences on Interneuron Diversity and Maturation. Cell Rep 21:721-731
Muñoz, William; Tremblay, Robin; Levenstein, Daniel et al. (2017) Layer-specific modulation of neocortical dendritic inhibition during active wakefulness. Science 355:954-959

Showing the most recent 10 out of 36 publications