passages.id: split_6_test_1310_passage
passages.type: progene_text
passages.text: DNaseI hypersensitivity studies uncovered a prominent DNaseI hypersensitivity site , located within a 315 - base pair ( bp ) fragment at the 5'-end of the 3 - kb segment , in transcriptionally active CaCo-2 cells but not in transcriptionally inactive HeLa cells .