Incision activity in protein
extracts from fractions containing different germ cell stages. (A) A 147mer DNA substrate containing a C4′ pivaloyl
adduct (lanes 1–4) or a dG-C8-AAF adduct (lanes 5–8)
incorporated in a stretch of three consecutive mispairs was incubated
with protein extracts from fractionated germ cell populations enriched
for early pachytene (E2.4) (lanes 1 and 5), mid pachytene (E4) (lanes
2 and 6), diplotene (E5) (lanes 3 and 7) or round spermatids (E2.1)
(lanes 4 and 8). (B) A 147mer DNA substrate containing a
C4′ pivaloyl adduct (lanes 9–15)
or no adduct (lane 16) incorporated in a stretch of three consecutive
mispairs was incubated with protein extracts from early pachytene
(E2.4) (lanes 9 and 16), mid pachytene (E4) (lane 10), diplotene
(E5) (lane 11), round spermatids (E2.1) (lane 12), HeLa cells (lane
13), mouse erythroleukemia cells (lane 14) or mouse embryonic fibroblasts
(lane 15).