Mosaic expression of Atrx in the mouse central nervous system causes memory deficits

Dis Model Mech. 2017 Feb 1;10(2):119-126. doi: 10.1242/dmm.027482. Epub 2017 Jan 12.

Abstract

The rapid modulation of chromatin organization is thought to play a crucial role in cognitive processes such as memory consolidation. This is supported in part by the dysregulation of many chromatin-remodelling proteins in neurodevelopmental and psychiatric disorders. A key example is ATRX, an X-linked gene commonly mutated in individuals with syndromic and nonsyndromic intellectual disability. The consequences of Atrx inactivation for learning and memory have been difficult to evaluate because of the early lethality of hemizygous-null animals. In this study, we evaluated the outcome of brain-specific Atrx deletion in heterozygous female mice. These mice exhibit a mosaic pattern of ATRX protein expression in the central nervous system attributable to the location of the gene on the X chromosome. Although the hemizygous male mice die soon after birth, heterozygous females survive to adulthood. Body growth is stunted in these animals, and they have low circulating concentrations of insulin growth factor 1. In addition, they are impaired in spatial, contextual fear and novel object recognition memory. Our findings demonstrate that mosaic loss of ATRX expression in the central nervous system leads to endocrine defects and decreased body size and has a negative impact on learning and memory.

Keywords: ATRX; Central nervous system; Mouse models; Neurobehaviour.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Weight
  • Brain / metabolism
  • Brain / pathology
  • Brain / physiopathology
  • Central Nervous System / metabolism
  • Central Nervous System / pathology*
  • Central Nervous System / physiopathology
  • Fear
  • Female
  • Gene Deletion
  • Gene Expression Regulation
  • Growth and Development
  • Hand Strength
  • Heterozygote
  • Hindlimb / pathology
  • Insulin-Like Growth Factor I / metabolism
  • Maze Learning
  • Memory Disorders / blood
  • Memory Disorders / genetics
  • Memory Disorders / physiopathology*
  • Memory, Short-Term
  • Mice
  • Mosaicism*
  • Motor Activity
  • Phenotype
  • Spatial Memory
  • Survival Analysis
  • X-linked Nuclear Protein / genetics
  • X-linked Nuclear Protein / metabolism*

Substances

  • Insulin-Like Growth Factor I
  • Atrx protein, mouse
  • X-linked Nuclear Protein

Grants and funding