Andrés E. Chávez, Ph.D.
Associate professor, Centro Interdisciplinario de Neurociencia,
Facultad de Ciencias, Universidad de Valparaíso
Instructor, Department of Neuroscience, Albert Einstein College of Medicine, NY. USA (2013-2015).
MSc and Ph.D. in Biological Sciences, Neuroscience, Universidad de Valparaíso, Chile.
Address: Centro de Interdisciplinario de Neurociencia de Valparaiso,
Facultad de Ciencias, Universidad de Valparaíso.
Avda. Gran Bretaña 1111, Casilla 5029, Correo 4. Valparaíso, Chile.
All our behaviors and feelings, memories and thoughts rely on the interaction between neurons via synapses. Information transfer at the synapse, called synaptic transmission, is critical for proper brain function. Neuromodulatory systems play an important role in regulating synaptic function and plasticity, and dysregulation of these mechanisms underlies several neurological disorders and pathological conditions. While synaptic factors that tune excitatory and inhibitory synapses vary widely over neuronal circuitries, the relative importance of these factors in determining brain activity is not well understood.
The main interest of my lab is to understand the cellular and molecular events by which endogenous neuromodulators tune synaptic transmission and plasticity at excitatory and inhibitory synapses. To this end, we investigate how different neuromodulatory systems (e.g. endocannabinoids, opioids, serotonin, and dopamine) regulate synaptic function by studying the biophysical and physiological properties of individual synapses within different neuronal circuits. In particular, we focus on the retinal circuitry, where modulation of synaptic function will have profound influence on how we see the external world. In addition, we examine the hippocampus and prefrontal cortex, where modulation of synaptic transmission affects higher cognitive processes such as learning and memory. We use a combination of tools including electrophysiology, optogenetics, in vivo knock-down strategies, and cellular biology approaches to understand: (1) the functional role of endocannabinoid signaling in retinal synaptic function; and (2) how serotonin and opioid receptors modulate excitatory and inhibitory synapses to regulate behavior. By studying the mechanisms underlying neuronal communication and its regulation by neuromodulators, we expect to uncover important principles of nervous system function at the cellular level, allowing us to integrate this information into a larger framework from which to investigate aspects of retinal disorders as well as neuropsychiatric disorders.
Selected publications (PubMed):
- Kalinowska M, Chávez AE, Lutzu S, Castillo PE, Bukauskas FF, Francesconi A. Actinin-4 Governs Dendritic Spine Dynamics and Promotes their Remodeling by Metabotropic Glutamate Receptors. J Biol Chem. 290(26):15909-20
- Tindi JO, Chávez AE, Cvejic S, Calvo-Ochoa E, Castillo PE, Jordan BA. (2015) ANKS1B Gene Product AIDA-1 Controls Hippocampal Synaptic Transmission by Regulating GluN2B Subunit Localization. J Neurosci. 2015 Jun 17;35(24):8986-96.
- Chávez A.E*, Hernandez VM, Rodenas-Ruano A, Chan CS, Castillo PE* (2014). Compartment-specific modulation of GABAergic synaptic transmission by TRPV1 channels in the dentate gyrus. J. Neurosci. 10;34(50):16621-9 *Corresponding author
- Hou H, Chávez AE, Wang CC, Yang H, Gu H, Siddoway BA, Hall BJ, Castillo PE, Xia H. (2014) The Rac1 inhibitor NSC23766 suppresses CREB signaling by targeting NMDA receptor function. J Neurosci. 2014 Oct 15;34(42):14006-12
- Rodenas-Ruano A*, Chávez A.E*, Cossio MJ, Castillo PE, Zukin RS. (2012). REST-dependent epigenetic remodeling promotes the developmental switch in synaptic NMDA receptors. *Equal contribution. Nature Neuroscience 15(10):1382-1390
- Castillo PE., Yount TH, Chávez A.E, Hashimotodani Y. (2012). Endocannabinoid signaling and synaptic function. Neuron, 76(1):70-81
- Chávez A.E, Chiu C.Q, Castillo P.E. (2010). TRPV1 activation by endogenous anandamide triggers postsynaptic long-term depression in dentate gyrus. Nature Neuroscience, 13(12):1511–1518.
- Chávez A.E, Grimes WN, Diamond J.S. (2010). Mechanisms underlie non-reciprocal GABAergic feedback transmission onto rod bipolar cells in rat retina. J. Neuroscience, 30(6):2330-9.
- Kaeser PS, Deng L, Chávez A.E, Castillo PE, Südhof TC (2009). ELKS2alpha/CAST Deletion Selectively Increase Neurotransmitter Release at Inhibitory synapses. Neuron, 64 (2):227-239
- Grimes WN, Li W, Chávez A.E, Diamond J.S. (2009). Rapidly inactivating BK channels modulate pre- and post-synaptic signaling at a reciprocal feedback synapse in the retina. Nature Neuroscience, 12(5):585-92.
- Chávez A.E, Diamond J.S. (2008). Diverse mechanisms underlie glycinergic feedback transmission onto rod bipolar cells in rat retina. J. Neuroscience 28 (31): 7919-7928
- Chávez A.E., Singer J.H, Diamond J.S. (2006). Fast neurotransmitter release triggered by Ca influx through AMPA-type glutamate receptor. Nature 443 (7112): 705-708
Our lab has close collaboration with the other members of the Circuits and Systems Neuroscience group at the CINV and with Drs. Pablo Moya (UV), Marco Fuenzalida (UV) and Gloria Arriagada (UNAB), with whom we aim to elucidate the mechanism underlying modulation of synaptic function in different neuronal circuits implicated in mood and anxiety disorders. Our lab also has strong collaboration with outstanding international scientists (e.g. Jeff Diamond, Pablo Castillo, and Yuki Hashimotodani).