an RNA-binding protein that recruits target transcripts to cytoplasmic protein-RNA complexes (mRNPs). This transcript 'caging' into mRNPs allows mRNA transport and transient storage. It also modulates the rate and location at which target transcripts encounter the translational apparatus and shields them from endonuclease attacks or microRNA-mediated degradation. Plays a direct role in the transport and translation of transcripts required for axonal regeneration in adult sensory neurons. Regulates localized beta-actin/ACTB mRNA translation, a crucial process for cell polarity, cell migration and neurite outgrowth. During neuronal development, key regulator of neurite outgrowth, growth cone guidance and neuronal cell migration, presumably through the spatiotemporal fine tuning of protein synthesis, such as that of ACTB. May regulate mRNA transport to activated synapses. Co-transcriptionally associates with the ACTB mRNA in the nucleus. This binding involves a conserved 54-nucleotide element in the ACTB mRNA 3'-UTR, known as the 'zipcode'. The RNP thus formed is exported to the cytoplasm, binds to a motor protein and is transported along the cytoskeleton to the cell periphery. During transport, prevents ACTB mRNA from being translated into protein. When the RNP complex reaches its destination near the plasma membrane, IGF2BP1 is phosphorylated. This releases the mRNA, allowing ribosomal 40S and 60S subunits to assemble and initiate ACTB protein synthesis. Monomeric ACTB then assembles into the subcortical actin cytoskeleton. Binds to the 3'-UTR of CD44 mRNA and stabilizes it, hence promotes cell adhesion and invadopodia formation in cancer cells. Promotes the directed movement of tumor-derived cells by fine-tuning intracellular signaling networks. Mainly expressed in the embryo, including in fetal liver, fetal lung, fetal kidney, fetal thymus. Also expressed follicles of ovary, as well as in gonocytes of testis, spermatogonia, semen, oocytes and placenta. Expressed in various cancers, including testis and lung cancers, as well as kidney, prostate and trachea cancers. 2 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Biological Process: CRD-mediated mRNA stabilization; mRNA transport; negative regulation of translation; neuronal stem cell population maintenance; pallium cell proliferation in forebrain; regulation of mRNA stability involved in response to stress; regulation of translation; RNA localization