Frontiers in Molecular Neuroscience (Nov 2019)

MIM-Deficient Mice Exhibit Anatomical Changes in Dendritic Spines, Cortex Volume and Brain Ventricles, and Functional Changes in Motor Coordination and Learning

  • Rimante Minkeviciene,
  • Iryna Hlushchenko,
  • Anaïs Virenque,
  • Anaïs Virenque,
  • Lauri Lahti,
  • Pushpa Khanal,
  • Pushpa Khanal,
  • Tuomas Rauramaa,
  • Arto Koistinen,
  • Ville Leinonen,
  • Ville Leinonen,
  • Ville Leinonen,
  • Francesco M. Noe,
  • Francesco M. Noe,
  • Pirta Hotulainen

DOI
https://doi.org/10.3389/fnmol.2019.00276
Journal volume & issue
Vol. 12

Abstract

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In this study, we performed a comprehensive behavioral and anatomical analysis of the Missing in Metastasis (Mtss1/MIM) knockout (KO) mouse brain. We also analyzed the expression of MIM in different brain regions at different ages. MIM is an I-BAR containing membrane curving protein, shown to be involved in dendritic spine initiation and dendritic branching in Purkinje cells in the cerebellum. Behavioral analysis of MIM KO mice revealed defects in both learning and reverse-learning, alterations in anxiety levels and reduced dominant behavior, and confirmed the previously described deficiency in motor coordination and pre-pulse inhibition. Anatomically, we observed enlarged brain ventricles and decreased cortical volume. Although MIM expression was relatively low in hippocampus after early development, hippocampal pyramidal neurons exhibited reduced density of thin and stubby dendritic spines. Learning deficiencies can be connected to all detected anatomical changes. Both behavioral and anatomical findings are typical for schizophrenia mouse models.

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