Synaptopodin is the founding member of a class of proline-rich actin-associated proteins and has been originally identified in podocytes of renal glomeruli (1, 2). In brain it localizes to the post-synaptic density (PSD) and the spine aparatus (1). In humans, three isoforms of synaptopodin with a distinct expression profile have been identified, neuronal Synpo-short, renal Synpo-long and Synpo-T. All three isoforms interact with alpha-actinin and induce alpha-actinin-induced actin filaments (3).
Synaptopodin deficient mice lack the dendritic spine apparatus and exhibit impaired activity-dependent long-term synaptic plasticity (4).