Epilepsy- and intellectual disability-associated CYFIP2 interacts with both actin regulators and RNA-binding proteins in the neonatal mouse forebrain.

Abstract

Variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) gene are associated with early-onset epileptic encephalopathy, intellectual disability, and developmental delay. However, the current understanding of the molecular functions of CYFIP2 is limited to those related to actin dynamics, and thus, the detailed mechanisms of CYFIP2-associated brain disorders remain largely unknown. Here, we isolated the neonatal forebrain CYFIP2 complex using newly generated Cyfip2-3×Flag knock-in mice, and performed mass spectrometry-based analyses to identify proteins in the complex. The CYFIP2 interactome, consisting of 140 proteins, contained not only the expected actin regulators but also 25 RNA-binding proteins (RBPs) including Argonaute proteins. Functionally, overexpression of brain disorder-associated CYFIP2 R87 variants, but not wild-type, inhibited stress granule formation in HeLa cells. Mechanistically, the CYFIP2 R87 variants formed intracellular clusters with Argonaute proteins under both basal and stress conditions, and thereby possibly preventing their assembly into stress granules. Beyond identifying CYFIP2 interactors in vivo, these results may provide novel insights for better understanding the molecular mechanisms of CYFIP2-associated brain disorders.

• Authors: Yeunkum Lee, Yinhua Zhang, Hyojin Kang, Geul Bang, Yoonhee Kim, Hyae Rim Kang, Ruiying Ma, Chunmei Jin, Jin Young Kim, Kihoon Han
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 529 Issue 1 Pg. 1-6 (08 13 2020) ISSN: 1090-2104 [Electronic] United States
• PMID: 32560809 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020 Elsevier Inc. All rights reserved.

Chemical References

• Actins
• Adaptor Proteins, Signal Transducing
• CYFIP2 protein, human
• Cyfip2 protein, mouse
• RNA-Binding Proteins

Topics

• Actins (metabolism)
• Adaptor Proteins, Signal Transducing (genetics, metabolism)
• Animals
• Animals, Newborn
• Disease Models, Animal
• Epilepsy (genetics, metabolism)
• Genetic Variation
• HeLa Cells
• Humans
• Intellectual Disability (genetics, metabolism)
• Mice
• Mice, Transgenic
• Prosencephalon (metabolism)
• Protein Interaction Maps
• RNA-Binding Proteins (metabolism)