passages.id: split_1_test_1476_passage
passages.type: progene_text
passages.text: To address the mechanisms of activation by CRP and the RNA polymerase alpha - subunit C - terminal domain ( alpha-CTD ) at rhaSR , we tested the effects of alanine substitutions in CRP activating regions 1 and 2 , overexpression of a truncated version of alpha ( alpha-Delta235 ) , and alanine substitutions throughout alpha-CTD .