Synaptic plasticity in the MyosinVa mutant mouse

Abstract

The trafficking of essential proteins into spines is an important aspect of synaptic plasticity. MyosinVa, an actin-based motor protein, has been implicated in the synaptic delivery of AMPARs during LTP [1]. However an earlier study showed that LTP and LTD were unaffected in the MyosinVa-null dilute-lethal mice [2]. To evaluate the role of MyosinVa in synaptic plasticity, we studied different forms of LTP and LTD in the CA1 region of the hippocanmpus from MyosinVa dominant negative mutant flailer mouse using field potential recordings. Flailer mice showed no impairment of LTP or NMDAR-dependent LTD, consistent with the findings of the study on dilute-lethal. In addition, MyosinVa has been implicated in the transport of an RNA-binding protein into the spines upon mGluR activation [3]. We explored protein synthesis and mGluR-dcpendent LTD in flailer. The preliminary data we obtained show a transient impairment in mGluR.-LTD, suggesting a role for MyosinVa in protein synthesis dependent plasticity.