A short unstructured region in NBR1 mediates interactions with MAP1LC3A, FIP200, and TAX1BP1. (A and B) HEK293T cells were co-transfected with full-length (FL) myc-TAX1BP1 and indicated BFP-V5-NBR1 truncations. Extracts derived from transfected cells were immunoprecipitated (IP) with protein G dynabeads conjugated with anti-V5 antibody. Input and eluates were resolved by SDS-PAGE followed by immunoblotting (IB) with the indicated antibodies. (C) A sliding frame peptide array spanning NBR1^711–759 was probed with 100 nM GST-MAP1LC3A, GST-FIP200^Claw (residues 1490–1594), or TAX1BP1^CC2-MBP (residues 346–506). Antibody-HRP conjugates were used to visualize binding to the arrays. Each spot represents a one residue register shift. (D) Quantification of HRP-derived intensities from C. Peptide sequences and corresponding positions in C are indicated (A1–E6). The canonical NBR1 LIR motif is indicated in blue. a.u., arbitrary units. Source data are available for this figure: SourceData F1.