Export receptor for importin alpha. Mediates importin-alpha re-export from the nucleus to the cytoplasm after import substrates have been released into the nucleoplasm (By similarity). Negatively regulates fluid secretion and plays a role in fluid homeostasis by down-regulating cftr activity (PubMed:20933420). Interacts with cftr (PubMed:20933420). Shuttles between the nucleus and the cytoplasm. Detected in larval gut, liver, exocrine pancreas and part of the brain and retina at 96 hpf. Morpholino knockdown of the protein causes strong expansion of the gut lumen, due to excessive fluid accumulation. Belongs to the XPO2/CSE1 family.