Neurons in local neuronal circuits are interconnected via synaptic connections that can experience dramatic changes in strength during ongoing neuronal activity. How synapses are regulated on a time scale of tens of milliseconds to tens of seconds is not well understood. Our laboratory uses a combination of electrophysiology, imaging, and optogenetics to explore the dynamic properties of distinct types of synapses in the thalamocortical system of rodents. We are particularly interested in the mechanisms underlying short-term synaptic plasticity and their importance for proper functioning of local neuronal circuits. Ultimately this knowledge will aid in understanding the computations performed in neuronal networks that mediate perception, memory formation and higher cognitive functions.
Optical stimulation of cholinergic afferents in the thalamic reticular nucleus generates thalamic network activity. Left: Channelrhodopsin-expressing cholinergic axons from the basal forebrain labeled by GFP target the thalamic reticular nucleus (TRN) but not the ventral posteromedial nucleus of the thalamus (VPM). Right: Schematic of cholinergic synaptic signaling in the TRN, mediated by both nicotinic and muscarinic receptors (top). TRN postsynaptic responses, evoked by optical stimulation of cholinergic axons (bottom).
Gibson, JR, Beierlein, M, Connors, BW. (1999) Two networks of electrically coupled inhibitory neurons in neocortex. Nature 402,75-79.
Beierlein, M, Gibson, JR, Connors, BW. (2000) A network of electrically coupled interneurons drives synchronized inhibition in neocortex. Nat. Neurosci. 3, 904-910.
Beierlein, M, Fall, CP, Rinzel, J, Yuste R. (2002) Thalamocortical bursts trigger recurrent activity in neocortical networks: layer 4 as a frequency-dependent gate. J. Neurosci. 22, 9885-9894.
Beierlein, M, Gibson, JR, Connors, BW. (2003) Two dynamically distinct inhibitory networks in layer 4 of the neocortex. J. Neurophysiol. 90, 2987-3000.
Beierlein, M, Gee, KR, Martin, VV, Regehr, WR. (2004) Presynaptic calcium measurements at physiological temperatures using a new class of dextran-conjugated indicators. J. Neurophysiol. 92, 591-599.
Beierlein, M, Regehr, WG. (2006) Brief bursts of parallel fiber activity trigger calcium waves in Bergmann glia. J. Neurosci. 26, 6958-6967.
Beierlein, M, Regehr, WG. (2006) Local interneurons regulate synaptic strength by retrograde release of endocannabinoids. J. Neurosci. 26, 9935-9943.
Beierlein, M, Fioravante, D, Regehr, WG. (2007) Differential expression of post-tetanic potentiation and retrograde signaling mediate target-dependent short-term synaptic plasticity. Neuron 54(6), 949-959.
Myoga, M, Beierlein, M, Regehr, WG. (2009) Somatic spikes regulate dendritic signaling in small neurons in the absence of backpropagating action potentials. J. Neurosci. 29, 7803-7814.
Sun, Y-G, Beierlein, M. (2011) Receptor saturation controls short-term synaptic plasticity at corticothalamic synapses. J. Neurophysiol. 105, 2319-2329.
Sun, Y-G, Wu, C-S, Lu, H-C, Beierlein, M. (2011) Target-dependent control of synaptic inhibition by endocannabinoids in the thalamus. J. Neurosci. 31, 9222-9230.
Sun, Y-G, Wu, C-S, Renger, JJ, Uebele, VN, Lu, H-C, Beierlein, M. (2012) GABAergic synaptic transmission triggers action potentials in thalamic reticular nucleus neurons. J. Neurosci. 32, 7782-7790.
Sun, Y-G, Pita Almenar, JD, Wu, CS, Renger, JJ, Uebele, VN, Lu, H-C, Beierlein, M. (2013) Biphasic cholinergic synaptic transmission in the thalamic reticular nucleus. J. Neurosci. 33, 2248-2259.
Beierlein, M. (2014) Synaptic mechanisms underlying cholinergic control of thalamic reticular nucleus neurons. J. Physiol. (Review) 592, 4137-4145.
Pita-Almenar, J.D., Yu, D., Lu, H.C., and Beierlein, M. (2014) Mechanisms underlying desynchronization of cholinergic-evoked thalamic network activity. J. Neurosci. 34, 14463-14474.
Search PubMed for additional articles.
|Synchronous activity in inhibitory neocortical neurons interconnected by electrical synapses.|