Fig. 5. ns156 alters MLS-2, an Nkx/HMX-related homeodomain protein. (A) mls-2(ns156) rescue studies. Strains were scored as in Fig. 4. VL/R, ventral left/right CEPsh glia. n, number of animals. C39E6, mls-2 cosmid. One representative line is shown for each construct. The mls-2 genomic locus construct contains 8.3 kb surrounding and including the gene. (B) C. elegans mls-2 gene structure. Boxes, exons; -shaped lines, introns; the homeodomain is in blue. (C) Alignment of homeodomains and HMX motifs of MLS-2 and related proteins. Pink, identical in all; blue, identical in all but one or two proteins; gray, present in five proteins. (D-J) (D) Diagram of ventral nuclei positions in a 270-minute embryo [adapted with permission from Sulston et al. (Sulston et al., 1983)]. (E,H) Enlarged regions of D, (F,I) DIC and (G,J) fluorescence images of a ventral right (E-G) and left (H-J) CEPsh glial cell precursor (red arrowhead) in a 270-minute embryo expressing mls-2::GFP. (K-N) Same as D-G but showing dorsal left and right CEPsh glia precursors.