passages.id: split_6_test_3263_passage
passages.type: progene_text
passages.text: Northern blot and reverse transcription - PCR analysis confirmed the presence of transcripts for all the ars genes , the expression of arsB3 and arsC4 being constitutive , and the expression of arsR1 , arsB1 , arsC1 , arsC1 ' , arsR2 , arsB2 , and arsC2 being inducible by arsenite .