opIs56 [egl-1p::2xNLS::GFP]. opIs56 is a low copy integrant of 3 kb 5' sequence from egl-1 fused to 2xNLS GFP. unc-119(ed3) should be outcrossed. Low basal GFP expression in embryos, meiotic germ cells and several neurons. GFP expression can be induced by ionizing radiation in all germ cells. Best viewed with dissected gonads.