Figure 7.

Screening for Ecta mutants using col-19::che-1 misexpression. A: Worms expressing che-1 under the control of an early epidermal promoter are not viable, displaying gcy-5::gfp fluorescence in the epidermis at the L1 stage (no stable lines could be established)(Patel and Hobert 2017), whereas animals with a col-19::che-1 transgene (otIs642) are fertile and do not express gcy-5::gfp in the epidermis at any stage (panel C). In this screen, mutants are isolated in which gcy-5::gfp is seen in the epidermis at the adult stage, when che-1 is expressed. Included is a schematic of col-19::che-1 transgene. B: P0 animals are mutagenized, F1s are split among 10 plates, and F2s are screened using the COPAS Biosort “Wormsorter” for the Ecta phenotype. C: Mutants identified in this screen. Representative micrographs of mutants isolated in the screen. Top panel shows otIs642; ntIs1 alone, where no expression of gcy-5::gfp (ntIs1) is observed in the epidermis, despite che-1 expression. Panels on the right are higher magnification micrographs of the panels on the left. In all mutant strains strong gcy-5::gfp expression is observed in the epidermis.