oxSi87 [peel-1p::N-terminal 12 amino acids of PEEL-1::GFP::peel-1 3'UTR + Cbr-unc-119(+)] II. GFP is expressed in the spermatogenic germline. During spermatogenesis, GFP is packaged into sperm. Reference: Seidel HS, et al. PLoS Biol. 2011 Jul;9(7):e1001115.