Journal: bioRxiv
Article Title: Fine-tuning STEAP1 protein expression and purification to preserve its conformation and function
doi: 10.64898/2026.02.16.706263
Figure Lengend Snippet: A) Diagram of STEAP1 constructs. mEGFP: monomeric enhanced green fluorescent protein. B) Cell viability and VCD (Viable Cell Density) of cells expressing STEAP1 at different culturing timepoints. C) Western blot analysis of STEAP1 expression levels in relation to varying culturing durations. The asterisk denotes bands of STEAP1 positioned at the expected molecular weight. Arrows indicate bands of STEAP1 corresponding to the size of dimers and trimers. D) Measurement of STEAP1 expression levels in cells treated with heme additives (0.5 mM 5-Aminolevulinic acid HCl, 1 μM Hemin-Cl, and 5 μM Fe(III)Cl) or not via western blotting. An equal number of cells were used to prepare samples for each lane. E) FSEC analysis of the oligomeric status of STEAP1-mEGFP in cells treated with heme additives compared to those without additives. F) Cryo-EM structure of STEAP1 homotrimers (PDB: 8UCD), corresponding to the trimeric peak in . The heme moiety is shown in red, lipid in pink, and bound FAD in magenta.
Article Snippet: Following SDS-PAGE, proteins were transferred to nitrocellulose membranes, which were blocked using Blocking Buffer for Fluorescent Western Blotting (cat. no. MB-070, Rockland Immunochemicals) and incubated with monoclonal anti-FLAG antibodies (cat. no. F1804, Sigma).
Techniques: Construct, Expressing, Western Blot, Molecular Weight, Cryo-EM Sample Prep