(a) Presence of reactive antibodies against Bio-Rad Precision Plus All Blue protein marker in mouse sera. Marker proteins were separated by preparative 10% SDS-PAGE (left lane) and sera were tested with a Miniblotter 28 channel unit. M1, M2, M3: mouse 1, 2, 3; p: preimmune serum; i: immune serum after 3rd immunization. For better visualization, 5× more protein marker was loaded on the colorimetric lane than on the lanes used for Western blot analysis with the mouse sera. (b) Detection of commercial prestained protein molecular weight markers by the anti-BLUE monoclonal antibody. NEB: New England Biolabs Blue Prestained Protein Standard, broad range (P7706; 1 μl); Thermo: ThermoScientific Page Ruler Plus (26619; 1 μl); BioR1: Precision Plus Protein Unstained Protein Standard (161-0363; 2 μl); BioR2: Bio-Rad Precision Plus Protein All Blue Prestained Protein Standard (161-0373; 1 μl) separated by 10% SDS-PAGE and transferred to nitrocellulose membrane (left panel). The membrane was then incubated as described in Materials & Methods with anti-BLUE (right panel). (c) anti-BLUE does not cross-react with unstained proteins from whole cell lysates. 1: E. coli; 2: A. thaliana; 3: S. cerevisiae; 4: C. elegans; 5: D. melanogaster; 6: Chicken follicle; 7: CHO, Chinese hamster ovary; 8: Rat1, rat fibroblasts; 9: N2a, mouse neuroblastoma; 10: CV1, Green monkey epithelial; 11: Hela, human epithelial; M: Bio-Rad Precision Plus Protein All Blue (1 μl). Nitrocellulose membrane stained with Ponceau S (lower panel). The membrane was then incubated as described in Materials & Methods with anti-BLUE (upper panel). (d) Simultaneous detection of protein marker with detection of Lamin A/C. One of two identical blots containing the indicated lysates was incubated with anti-Lamin A/C antibody, clone 4C11, alone (left panel) or in combination with anti-BLUE (right panel). 1: HAP1 LMNA−, near-haploid human adherent cell line with a fibroblast-like morphology, lacking the LMNA gene; 2: HAP1 wildtype/control cells; 3: MEF LMNA−/−, mouse embryo fibroblasts lacking the LMNA gene; 4: MEF wildtype/control cells; M: Bio-Rad Precision Plus Protein All Blue (1 μl).