passages.id: split_4_test_1956_passage
passages.type: progene_text
passages.text: One involves the HuR shuttling domain , HNS , which exhibits a heat shock - sensitive interaction with transportin 2 ( Trn2 ) ; the other involves two protein ligands of HuR - pp32 and APRIL - which contain leucine - rich nuclear export signals ( NES ) recognized by the export receptor CRM1 .