10.2 Structural gene clusters are coordinately controlled PO 闷 DAAAAAAAAAAAAAA 104082 3510 780 825 mRNA Protein Repressor 阝 galactosidase Permease ransacetyase Figure 10.4 The lac operon occupies 6000 bp of DNA. At the left the lacl gene has its own promoter and terminator. The end of the lacl region is adjacent to the promoter, P. The operator, O occupies the first 26 bp of the long lacz gene, followed by the 请莘大 lacy and laca genes and a terminatorFigure 10.4 The lac operon occupies ~6000 bp of DNA. At the left the lacI gene has its own promoter and terminator. The end of the lacI region is adjacent to the promoter, P. The operator, O, occupies the first 26 bp of the long lacZ gene, followed by the lacY and lacA genes and a terminator. 10.2 Structural gene clusters are coordinately controlled