Title

Nuclear localization of EIF4G3 suggests a role for the XY body in translational regulation during spermatogenesis in mice.

Document Type

Article

Publication Date

11-17-2017

JAX Source

Biol Reprod 2017 Nov 17 [Epub ahead of print]

PMID

29161344

DOI

https://doi.org/10.1093/biolre/iox150

Grant

HD73077, CA034196

Abstract

Eukaryotic translation initiation factor 4G (EIF4G) is an important scaffold protein in the translation initiation complex. In mice mutation of the Eif4g3 gene causes male infertility, with arrest of meiosis at the end of meiotic prophase. This study documents features of the developmental expression and sub-cellular localization of EIF4G3 that might contribute to its highly specific role in meiosis and spermatogenesis. Quite unexpectedly, EIF4G3 is located in the nucleus of spermatocytes, where it is highly enriched in the XY body, the chromatin domain formed by the transcriptionally inactive sex chromosomes. Moreover, many other, but not all, translation-related proteins are also localized in the XY body. These unanticipated observations implicate roles for the XY body in controlling mRNA metabolism and/or "poising" protein translation complexes before the meiotic division phase in spermatocytes.