Recapitulation of the EEF1A2 D252H neurodevelopmental disorder-causing missense mutation in mice reveals a toxic gain of function

Faith C.J. Davies, Jilly E. Hope, Fiona McLachlan, Grant F. Marshall, Laura Kaminioti-Dumont, Vesa Qarkaxhija, Francis Nunez, Owen Dando, Colin Smith, Emma Wood, Josephine MacDonald, Oliver Hardt, Catherine M. Abbott

Research output: Contribution to journalArticlepeer-review

Abstract

Heterozygous de novo mutations in EEF1A2, encoding the tissue-specific translation elongation factor eEF1A2, have been shown to cause neurodevelopmental disorders including often severe epilepsy and intellectual disability. The mutational profile is unusual; ~50 different missense mutations have been identified but no obvious loss of function mutations, though large heterozygous deletions are known to be compatible with life. A key question is whether the heterozygous missense mutations operate through haploinsufficiency or a gain of function mechanism, an important prerequisite for design of therapeutic strategies. In order both to address this question and to provide a novel model for neurodevelopmental disorders resulting from mutations in EEF1A2, we created a new mouse model of the D252H mutation. This mutation causes the eEF1A2 protein to be expressed at lower levels in brain but higher in muscle in the mice. We compared both heterozygous and homozygous D252H and null mutant mice using behavioural and motor phenotyping alongside molecular modelling and analysis of binding partners. Although the proteomic analysis pointed to a loss of function for the D252H mutant protein, the D252H homozygous mice were more severely affected than null homozygotes on the same genetic background. Mice that are heterozygous for the missense mutation show no behavioural abnormalities but do have sex-specific deficits in body mass and motor function. The phenotyping of our novel mouse lines, together with analysis of molecular modelling and interacting proteins, suggest that the D252H mutation results in a gain of function.
Original languageEnglish
Pages (from-to)1592–1606
JournalHuman Molecular Genetics
Volume29
Issue number10
Early online date11 Mar 2020
DOIs
Publication statusPublished - 15 May 2020

Fingerprint Dive into the research topics of 'Recapitulation of the EEF1A2 D252H neurodevelopmental disorder-causing missense mutation in mice reveals a toxic gain of function'. Together they form a unique fingerprint.

Cite this