Part of a ternary complex that binds to the downstream control sequence (DCS) of the pre-mRNA. Mediates exon inclusion in transcripts that are subject to tissue-specific alternative splicing. May interact with single-stranded DNA from the far-upstream element (FUSE). May activate gene expression. Also involved in degradation of inherently unstable mRNAs that contain AU-rich elements (AREs) in their 3'-UTR, possibly by recruiting degradation machinery to ARE-containing mRNAs. Binds to the dendritic targeting element and may play a role in mRNA trafficking (By similarity). Binds to a 54-nucleotide localization signal (the 'zipcode') found in the 3'-UTR of beta-actin mRNA and may play a role in its localization. Predominantly nuclear. The highest expression is found in 6-d embryos, is reduced to 30% before hatching and remains stable thereafter. Belongs to the KHSRP family.