FIGURE 4.

Vulval defects of the pst-1(tm3364) mutant. A, wild-type vulva forms an invagination space that looks like a pointed hat during early to mid-L4 stage (left). The pst-1(tm3364) mutation induced a collapse of the vulval invagination space (middle). In the mid-L4 stage, the pst-1(tm3364) vulva exhibited an ectopic invagination space (asterisk, right panel). Scale bar = 20 μm. B, penetrance in several genetic backgrounds of vulval morphological defects, including the squashed vulva and inappropriate vulval cell positioning. Ex, extrachomosomal array. C, the vulval structures of wild-type (left) and pst-1(tm3364) homozygote (right) animals were visualized with AJM-1·GFP. Incorrectly positioned cells are circled with a yellow dashed line. Scale bar = 20 μm. D, DIC and fluorescence images of pst-1(tm3364)/nT1 (left) and pst-1(tm3364) homozygote (right) mid-L4 animals that expressed P_lin-11::gfp. The pst-1(tm3364)/nT1 animals with the syIs80 transgene showed P_lin-11::gfp expression patterns similar to those of wild-type animals (data not shown). The GFP signals derived from the nT1[qIs51] balancer chromosome are indicated with asterisks. Arrowheads indicate VC motor neurons, and V/U indicates P_lin-11::gfp expression in the vulva and uterus. Bar = 200 μm. E, DIC and fluorescence images of pst-1(tm3364)/nT1 (left) and pst-1(tm3364) homozygote (right) vulvas during the L3 stage (Pn.pxx stage). GFP signals from VC motor neurons are indicated with asterisks. GFP signals from the uterus are indicated with arrows. Bar = 25 μm. F, DIC and fluorescence images of pst-1(tm3364)/nT1 (left) and pst-1(tm3364) (right) homozygote vulvas during the mid-L4 stage (Pn.pxxx stage). Bar = 25 μm.