Lasp1 is down-regulated in NMDA receptor antagonist-treated mice and implicated in human schizophrenia susceptibility

Mice treated with MK-801, a non-competitive antagonist of the N-methyl-d-aspartic (NMDA) acid receptor, are important animal models for schizophrenia studies. In the present study, we compared protein expression levels in the hippocampus of mice treated with MK-801 (0.6 mg/kg) or saline once daily for 7 days. Changes in the proteome were detected by two-dimensional electrophoresis, and the six proteins exhibiting differential expression were identified by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. Down-regulation of one of these proteins, Lasp1 (LIM and SH3 protein 1), in MK-801-treated mice was confirmed by western blotting and immunohistochemical analyses. Lasp1 is a multidomain protein that may recruit signaling molecules to the actin-based cytoskeleton and is known to concentrate in synaptic sites of hippocampal neurons. We next investigated whether polymorphisms in the human LASP1 gene were associated with schizophrenia in the Korean population. A single-nucleotide polymorphism in the LASP1 gene promoter region was associated with schizophrenia susceptibility. Our results suggest that LASP1 might be associated with NMDA receptor antagonism and schizophrenia susceptibility and, thus, might be involved in the pathophysiology of schizophrenia.