title: Basal levels of AMPA receptor GluA1 subunit phosphorylation at threonine 840 and serine 845 in hippocampal neurons.
abstract: Dephosphorylation of AMPA receptor (AMPAR) GluA1 subunits at two sites, serine 845 (S845) and threonine 840 (T840), is thought to be involved in NMDA receptor-dependent forms of long-term depression (LTD). Importantly, the notion that dephosphorylation of these sites contributes to LTD assumes that a significant fraction of GluA1 subunits are basally phosphorylated at these sites. To examine this question, we used immunoprecipitation/depletion assays to estimate the proportion of GluA1 subunits basally phosphorylated at S845 and T840. Although dephosphorylation of S845 is thought to have a key role in LTD, our results indicate that few GluA1 subunits in hippocampal neurons are phosphorylated at this site. In contrast, ∼50% of GluA1 subunits are basally phosphorylated at T840, suggesting that dephosphorylation of this site can contribute to the down-regulation of AMPAR-mediated synaptic transmission in LTD.
authors.affiliation: Department of Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA.
authors.forename: Walter E
authors.initials: WE
authors.lastname: Babiec
authors.affiliation: Interdepartmental Ph.D. Program for Neuroscience at UCLA, Los Angeles, California 90095, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Guglietta
authors.affiliation: Department of Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA UCLA Integrative Center for Learning and Memory, Brain Research Institute, Los Angeles, California 90095, USA todell@mednet.ucla.edu.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: O'Dell
mesh_terms: D000818:Animals; D006624:Hippocampus / Q000378:metabolism*; D047468:Immunoprecipitation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000378:metabolism*; D021122:Protein Subunits / Q000378:metabolism; D018091:Receptors, AMPA / Q000378:metabolism*; D012694:Serine / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism*
chemical_list: D021122:Protein Subunits; D018091:Receptors, AMPA; D012694:Serine; D013912:Threonine