C. elegans transgenes and transgenic lines for affinity purification of nuclei. (A) Schematic representation of the C. elegans nuclear targeting fusion (NTF) transgene, consisting of the muscle-specific myo-3 promoter, the whole genomic sequence of npp-9 for targeting to the nuclear envelope, mCherry for fluorescence visualization, biotin ligase recognition peptide (BLRP) as a substrate for biotinylation, and 3xFLAG for immunodetection, followed by the npp-9 3′UTR. The biotin tag is ligated in vivo to the lysine residue shown in bold within the sequence of the BLRP. (B) Schematic representation of the birA::gfp transgene, consisting of the E. coli biotin ligase birA fused to gfp, flanked by the his-72 promoter and 3′ UTR. (C,D) Adult transgenic C. elegans showing expression of the NTF targeted to the nuclei of muscle cells. mCherry fluorescence (C) and DIC image (D).
