Gel-retardation experiments showing the effects of
the preincubation of plastid extracts with either ATP, ADP,
phosphocreatine and phosphocreatine kinase, and/or an inhibitor of
adenylate kinase. A, Gel-shift assays were done using radiolabeled GT30
DNA fragments and plastid extracts, which were preincubated with either
5.0 mm ATP or 1.0 mm ADP in the presence of 5.0
mm phosphocreatine (PC) and 2 units of phosphocreatine
kinase (PC Kin) (lanes 3 and 5, respectively). Binding reactions using
plastid extracts preincubated with 5.0 mm ATP or 1.0
mm ADP alone are shown in lanes 2 and 4, respectively.
Plastid extracts were obtained from 4.5-d-old, dark-grown barley
plants. The major complexes observed using the extracts without any
additions (control reaction, lane 1) are labeled I, II, and III.
Migration of the free probe (FP) is indicated. B, Gel-retardation
experiments using radiolabeled LRP136 DNA probe testing the effect of
preincubation of plastid extracts with ADP in the presence of the
adenylate kinase inhibitor Ap5A. Plastid extracts were preincubated,
before binding reactions, with 1.0 mm Ap5A in the presence
(1.0 mm, lane 3) or absence (lane 2) of ADP. The major
complexes observed in plastid extracts without additions are labeled A,
B, C, D, and E (Control, lane 1). Migration of the free probe (FP) is
indicated.