The effect of increasing doses of the 5′-UTR with
site 1 deleted on the activity of the I factor promoter.
The vertical axis indicates the CAT activity (pmol/min/mg of
protein) in ovarian extracts from females obtained as indicated below.
The horizontal axis indicates the number of copies of the deleted
5′-UTR per haploid genome. Females of strains with 0, 2, 3, or 5 copies
of the deleted 5′- UTR per haploid genome were crossed with males
carrying the 1–186:CAT reporter gene. This gave progeny with 0, 2, 3,
or 5 copies of the deleted 5′-UTR per haploid genome. The black circles
indicate the results of crosses using females of strains CΔ9H,
PΔ40H, and CΔ9PΔ40H whereas the white circles indicate the
results for strains CΔ57H, PΔ20H, and CΔ57PΔ20H (Table 1).