Superficially wild-type. CRISPR/Cas9 engineered STOP-IN null mutant of col-137. Universal 43bp-long knock-in insertion with 3-frame stop codon (STOP-IN cassette). left flanking sequence: GAATCGCAATTTCCACGATTGCAACTCTGACCGCTA right flanking sequence: TCTTGGCAATTCCAATGTTGTACAATTACATGCAAC inserted sequence between the two flanking sequence (STOP-IN cassette): GGGAAGTTTGTCCAGAGCAGAGGTGACTAAGTGATAAgctagc. sgRNA: TGCAACTCTGACCGCTATCT Method Reference: G3 (Bethesda).