Figure 3. β-galactosidase expression in transgenic wild-type and heterochronic mutant animals transformed with
col-19/lacZ (pZC19.61) and col- 7/lacZ (pZC7.21) reporter genes (Materials and Methods; Fig. 2). The rolling phenotype conferred by the
rol-6(
su1006) transformation marker (Mello et al., 1991) is recognizable in fixed animals by a twist in the worm's body. (A,B) Wild-type hermaphrodites at the L4-to-adult molt and adult stages, respectively, transformed with the
col-19/lacZ reporter. The nuclear localization signal included in the reporter gene product (Fig. 2) directs β-galactosidase to the nuclei of expressing seam (se) cells and syncytial (sy) cells. β-galactosidase staining appeared first in vulva cells at the L4-to-adult molt; then, in seam cells of young adults; finally, in syncytial cells and non-vulval ventral hypodermal cells of older adults. (C) β-galactosidase expression in the hypodermal seam of a wild-type adult hermaphrodite transformed with the
col-7/lacZ reporter. β-galactosidase staining was adult-specific and restricted to the seam cells. The fusion protein produced from this construct lacks a nuclear localization signal, so much of the β-galactosidase activity is extranuclear. (D) Wild-type larvae (L) and adult (A) hermaphrodites transformed with the
col-19/lacZ fusion. (E)
lin-28(
n719) larvae transformed with
col-19/lacZ. (F)
lin-29(
n546) adult transformed with col- 19/lacZ. Note the staining near the protruding vulva. (G) Wild-type larva (L) and adult (A) hermaphrodites transformed with the
col-7/lacZ. (The non-expressing adult at left was not a roller). (H)
lin-14(
n360) larva (L) and adult (A) hermaphrodites transformed with
col-7/lacZ. (I)
lin-4(
e912) adult transformed with
col-19/lacZ. Bar for A-C, 20 μm; for D-I, 100 μm.