Promotes phosphorylation of the Wnt coreceptor LRP6, leading to increased activity of the canonical Wnt signaling pathway (PubMed:18762581). Facilitates constitutive LRP6 phosphorylation by CDK14/CCNY during G2/M stage of the cell cycle, which may potentiate cells for Wnt signaling (PubMed:27821587). May regulate the transport and translation of mRNAs, modulating for instance the expression of proteins involved in synaptic plasticity in neurons (By similarity). Involved in regulation of growth as erythroblasts shift from a highly proliferative state towards their terminal phase of differentiation (PubMed:14593112). May be involved in apoptosis (PubMed:14593112). {ECO:0000250|UniProtKB:Q05A80, ECO:0000269|PubMed:14593112, ECO:0000269|PubMed:18762581, ECO:0000269|PubMed:27821587}. This is the function of Ensembl gene identifier ENSG00000110888 (CAPRIN2, caprin family member 2).