Fig. 5. let-756 functions non-autonomously to regulate muscle membrane extension. (A-D) LET-756::YFP expression from RP195 Ex[let-756p::LET-756::YFP; let-756p::DsRed]; let-756(s2887) unc-32(e189) III animals. Scale bar: 5 µm. (A) The anterior dorsal BWMs show LET-756::YFP expression in the nucleus (black arrow) and at the sites of BWM-BWM contacts (yellow arrow). (B) Nuclear localization of LET-756::YFP (arrow) in a CAN neuron. (C) RFP channel of the same cell in B. (D) A DIC image of the same cell in B. The arrow indicates the same spot as in B. (E,F) An RP175 Ex[let-756p::YFP; let-756p::LET-756]; let-756(s2887) unc-32(e189) III animal. Expression of let-756 in two BWMs (arrow, F) is sufficient to rescue the lethality associated with a let-756(s2887) null mutation, and can locally rescue the scrawny phenotype (arrow, E). Scale bar: 50 µm. (G) let-756 expression from either the 3.0 kb let-756 promoter/enhancer sequence, a pan-neuronal promoter (F25B3.3p) or a hypodermal promoter (dpy-7p) in a let-756(s2887) null background confers significantly fewer EMEs (red asterisks) than let-756(s2887) null escapers without the rescuing arrays (P<0.001). Black asterisks indicate significantly more EMEs than in trIs10 or trIs10; unc-32(e189) controls (P<0.001). n values are indicated for each genotype within each bar and error bars represent the s.e.m.