Ribosome-binding protein that promotes ribosome hibernation, a process during which ribosomes are stabilized in an inactive state and preserved from proteasomal degradation (By similarity). Acts via its association with EEF2/eEF2 factor at the A-site of the ribosome, promoting ribosome stabilization in an inactive state compatible with storage (By similarity). Plays a key role in ribosome hibernation in the mature oocyte by promoting ribosome stabilization (By similarity). Ribosomes, which are produced in large quantities during oogenesis, are stored and translationally repressed in the oocyte and early embryo (By similarity). Also binds RNA, regulating transcription and pre-mRNA splicing ( , ). Binds (via C-terminus) to poly(U) RNA . Seems to play a role in PML-nuclear bodies formation . Negatively regulates DNA-binding activity of the transcription factor MEF2C in myocardial cells in response to mechanical stress (By similarity).
Subcellular locations: Nucleus, Cytoplasm, Cytoplasm, Stress granule, Cytoplasm, Sarcoplasm, Nucleus, Nuclear body, Nucleus, Nucleolus, Nucleus speckle, Nucleus, Cajal body, Nucleus, Gem
Transported into the nuclear compartment in activated leukocytes . Inhibition of methylation alters its distribution between the nuclear and cytoplasmic compartments (, ). Methylation may be required for its localization in subnuclear structures, such as nucleoli, nuclear speckles, Cajal bodies and Gemini of coiled bodies (gems) . Colocalizes with FMR1, FXR1 and FXR2 in cytoplasmic stress granules . In myocardial cells, localization at the sarcoplasm is reduced in response to mechanical stress (By similarity).
Highly expressed in brain, heart, and kidney, and moderately expressed in skeletal muscle. Also expressed in a variety of tumor cell lines and in activated but not resting leukocytes.