ELAVL1/HuR, like other ELAVL proteins, has a short N-terminal region followed by 2 RNA-binding motifs, a basic linker domain, and a third RNA-binding motif. The basic hinge region bears a novel nuclear-shuttling domain, which is implicated in the nucleocytoplasmic HuR shuttling. Unlike its neuron-specific ELAV relatives (HuB, HuC and HuD), HuR is ubiquitously expressed. Structure-function analyses of HuR have shown that it binds to AU-rich mRNA sequences in the nucleus and may be involved in their nuclear export.