The crystal structure of the human exportin-5 (XPO5) protein (red, composed of HEAT repeats) in complex with Ran-GTP (yellow) and a pre-microRNA (green), with the two-nucleotide overhang that serves as an XPO5 recognition element shown in orange spheres at the top of the figure. This complex is involved in the export of pre-miRNA from the cell nucleus (where it was generated by the Microprocessor complex of Drosha and DCGR8) to the cytoplasm (where it will be further processed by Dicer). Rendered with PyMol from PDB ID 3A6P.