TRX-1 regulates intestinal SKN-1 nuclear localization in a redox-independent fashion. Fluorescence microscopy was used to analyze the intestinal nuclear localization of SKN-1::GFP in (A) wild type, (B) trx-1 mutants, trx-1 mutants complemented with either (C) wild-type trx-1 or (D) redox dead trx-1. Worms were visualized using a 20× objective. Blue boxes indicate the portion of the micrograph field that is magnified in the boxes below each micrograph. (E) Percentage of SKN-1::GFP nuclear localization was categorically scored and quantified as described in Materials and Methods. While the percentage of SKN-1::GFP nuclear localization increased over twofold upon loss of trx-1 (P-value < 0.0001), complementation with either wild-type or redox dead trx-1 restored proper SKN-1 localization (P-value = 0.3843 and P-value = 0.1931, as compared to wild type, respectively). Percentages are an average of three biological replicates (n = 40 worms per replicate).