This gene encodes one member of a family of repressor of translation. The protein initiation that regulates EIF4E activity by preventing its assembly into the eIF4F complex, which is a limiting component of the multisubunit complex that recruits 40S ribosomal subunits to the 5' end of mRNAs. Interaction of this protein with eIF4E inhibits complex assembly and represses translation. Mediates the regulation of protein translation by hormones, growth factors and other stimuli that signal through the MAP kinase and mTORC1 pathways.