Binds to the GM-CSF promoter. Seems to act as a repressor. Binds also to full-length mRNA and to short RNA sequences containing the consensus site 5'-UCCAUCA-3'. May have a role in translation repression (By similarity). Found in a mRNP complex with YBX2. Interacts with RRP1B. Additional isoforms seem to exist. Abundant in the skeletal muscle, spleen and fetal liver.