Translation repressor. Component of the CYFIP1-EIF4E- FMR1 complex which binds to the mRNA cap and mediates translational repression. In the CYFIP1-EIF4E-FMR1 complex this subunit mediates translation repression. RNA- binding protein that plays a role in intracellular RNA transport and in the regulation of translation of target mRNAs. Associated with polysomes. May play a role in the transport of mRNA from the nucleus to the cytoplasm. Binds strongly to poly(G), binds moderately to poly(U) but shows very little binding to poly(A) or poly(C). Component of the CYFIP1-EIF4E-FMR1 complex which is composed of CYFIP, EIF4E and FMR1. Interacts with CYFIP1 and CYFIP2. The interaction with brain cytoplasmic RNA 1 (BC1) increases binding affinity for the CYFIP1-EIF4E complex in the brain. Homooligomer. Found in a RNP granule complex with IGF2BP1. Directly interacts with SMN and TDRD3. Interacts with the SMN core complex that contains SMN1, GEMIN2/SIP1, DDX20/GEMIN3, GEMIN4, GEMIN5, GEMIN6, GEMIN7, GEMIN8 and STRAP/UNRIP. Interacts with FXR1, FXR2, IGF2BP1, NUFIP1, NUFIP2, MCRS1 and RANBP9. Highest levels found in neurons, brain, testis, placenta and lymphocytes. Also expressed in epithelial tissues and at very low levels in glial cells. Belongs to the FMR1 family. 8 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.