Marc Nahmani, Ph.D. - US grants

[unreadable] DESCRIPTION (provided by applicant): [unreadable] [unreadable] Only sensory deprivation confined to a small developmental time window can alter the physiology and neuronal connectivity subserving ocular dominance in visual cortex. Following this period, the potential for dramatic reorganization is lost. GABAergic inhibition plays a permissive role in allowing for the onset of this 'critical period' plasticity, in addition to its probable involvement in critical period closure. Yet the specific subtype(s) of GABAergic neurons involved, and the mechanisms whereby they prevent ocular dominance plasticity have not been determined. Recent studies and preliminary data suggest that pan/albumin containing GABAergic interneurons are poised to play a key role in critical period modulation. This project aims to examine the role of pan/albumin interneuron connectivity during and after the critical period, in order to enhance our understanding of the structural events that eventually constrain ocular dominance plasticity. Furthermore, the long-term objective is to provide a detailed account of how inhibitory inputs are consolidated during developmental plasticity, to elucidate the conditions necessary to reinstitute cortical plasticity for possible therapeutic advantage. Pan/albumin interneurons receive nearly all the input from primary sensory thalamic axons to GABAergic circuitry in adult visual cortex. Moreover, their abundant gap junctions with one another throughout development may allow for widespread inhibitory control of specific excitatory cortical networks. These experiments seek to determine whether parvalbumin interneuron synapses to glutamatergic and GABAergic neuron subtypes in visual cortex are 'pruned' over the critical period, and the extent to which the maturation of these connections is accelerated following the GABAergic induction of premature critical period closure. The development of parvalbumin interneuron connectivity will be characterized using a line of GFP-parvalbumin mice, in conjunction with immuno-electron microscopy and chronic drug infusion. In addition, these studies will employ monocular deprivation and visually evoked potentials to assess whether increased cortical GABAergic activity and a precocious critical period closure is accompanied by a similarly premature consolidation of parvalbumin interneuron contacts. [unreadable] [unreadable] [unreadable]

An award is made to the University of Puget Sound to acquire a state-of-the-art transmission electron microscope to advance the nanoscale research of over 18 investigators at three primarily undergraduate institutions (PUIs): the University of Puget Sound, the University of Washington–Tacoma, and Pacific Lutheran University. Additionally, the TEM will offer a unique training opportunity for an estimated 200 undergraduate students annually who will use the instrument for research and in laboratory courses at their respective institutions. The procurement of this TEM will enable a collaboratively designed and run summer multimodal microscopy course-based research experience class, in which students across five local institutions will participate. This TEM will also play a central role in collaborative authentic research experiences with an estimated 60-80 local high school students each year.

The user-friendly and versatile microscope will be the only TEM in the South Puget Sound and will drive a host of research projects across labs within this region. These projects hold the potential to produce innovative results that could (1) lead to a comprehensive understanding of how bacterial biofilms are created; (2) create crucial new antibodies able to efficiently traverse the blood-brain barrier and remain in the brain; (3) revolutionize the manufacturing of solar cells and LEDs through uniform nanocrystal formation; (4) discover and characterize a novel form of neuronal communication and synapse stability; (5) lead to breakthroughs in bismuth nanoparticle synthesis and their biomolecular interactions; and (6) uncover the link between taste receptor function and motor behavior. This TEM will enable research that will result in numerous high-impact, undergraduate driven publications. Overall, the acquisition of this TEM will have a transformative effect on research and undergraduate education across disciplines and institutions in the South Puget Sound.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.