Pentraxins Coordinate Excitatory Synapse Maturation and Circuit Integration of Parvalbumin Interneurons

• Published in: Neuron (Cambridge, Mass.) Vol. 85; no. 6; pp. 1257 - 1272
• Main Authors: Pelkey, Kenneth A., Barksdale, Elizabeth, Craig, Michael T., Yuan, Xiaoqing, Sukumaran, Madhav, Vargish, Geoffrey A., Mitchell, Robert M., Wyeth, Megan S., Petralia, Ronald S., Chittajallu, Ramesh, Karlsson, Rose-Marie, Cameron, Heather A., Murata, Yasunobu, Colonnese, Matthew T., Worley, Paul F., McBain, Chris J.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 18.03.2015; Elsevier Limited
• Subjects: Action Potentials - physiology; Animals; Animals, Newborn; Behavior; C-Reactive Protein - deficiency; C-Reactive Protein - metabolism; Disease Models, Animal; Experiments; Interneurons - metabolism; Mice; Mice, Knockout; Nerve Net - growth & development; Nerve Tissue Proteins - deficiency; Nerve Tissue Proteins - metabolism; Parvalbumins - metabolism; Physiology; Recruitment; Rodents; Synapses - metabolism
• ISSN: 0896-6273; 1097-4199
• DOI: 10.1016/j.neuron.2015.02.020

Circuit computation requires precision in the timing, extent, and synchrony of principal cell (PC) firing that is largely enforced by parvalbumin-expressing, fast-spiking interneurons (PVFSIs). To reliably coordinate network activity, PVFSIs exhibit specialized synaptic and membrane properties that promote efficient afferent recruitment such as expression of high-conductance, rapidly gating, GluA4-containing AMPA receptors (AMPARs). We found that PVFSIs upregulate GluA4 during the second postnatal week coincident with increases in the AMPAR clustering proteins NPTX2 and NPTXR. Moreover, GluA4 is dramatically reduced in NPTX2−/−/NPTXR−/− mice with consequent reductions in PVFSI AMPAR function. Early postnatal NPTX2−/−/NPTXR−/− mice exhibit delayed circuit maturation with a prolonged critical period permissive for giant depolarizing potentials. Juvenile NPTX2−/−/NPTXR−/− mice display reduced feedforward inhibition yielding a circuit deficient in rhythmogenesis and prone to epileptiform discharges. Our findings demonstrate an essential role for NPTXs in controlling network dynamics highlighting potential therapeutic targets for disorders with inhibition/excitation imbalances such as schizophrenia. •GluA4 is undetectable in neonatal PVFSIs, then increases and plateaus by P15•NPTX2−/−/NPTXR−/− mice have profound loss of GluA4•PVFSI AMPAR function and recruitment are compromised in NPTX2−/−/NPTXR−/− mice•I/E imbalances in NPTX2−/−/NPTXR−/− mice impair rhythmogenesis and working memory Pelkey et al. demonstrate a critical role for neuronal pentraxins 2 and receptor (NPTX2/R) in regulating GluA4 expression within parvalbumin fast-spiking interneurons (PVFSIs). Circuit recruitment of PVFSIs is compromised in NPTX2−/−/NPTXR−/− mice, with consequent deficits in network rhythmogenesis and behavior.