Suppression of the phase 2 DTC defect was partial when RNAi was used to reduce EMB-9/collagen IV in
mig-6(
ev701) heterozygotes. Loss of precise DTC guidance along the DV axis of the lateral epidermis during the phase 2 migration is the phenotype of
mig-6(
ev701) heterozygous animals. Authors call this the class-s (class-short) defect as it is caused by disruption of the
mig-6 short isoform. Migration is not slow as seen with the disruption of the long isoform. In wildtype, phase 1 migration comprises a longitudinal migration in opposite directions away from the mid-body using the ventral body muscle basement membrane as a substratum for migration. During phase 2, the DTCs turn and migrate across the lateral epidermal basement membrane towards the dorsal body wall muscles.