Fig. 4

Characterization of AXIN1-295aa. a An IP assay was conducted to detect endogenous AXIN1-295aa using an anti-AXIN1 N-terminus antibody. Mass spectrometry was performed using the gel cut from 25 to 55 kDa following SDS-PAGE. b The recognized peptides from mass spectrometry match with AXIN1-295aa. The sequences are highlighted in green in c. c AXIN1-295aa is homologous to the N-terminus of full-length AXIN1 with two aa differences at position 294 to 295 aa. Two amino acids, “TD”, of circAXIN1, which were distinguishable from full-length AXIN1, were detected. Commercial antibodies recognizing the N-terminus of AXIN1 are available. d The antibody that recognizes the N-terminus of AXIN1 was able to detect endogenously and ectopically expressed AXIN1-295aa. Left: anti-FLAG antibody was used in immunoblotting to detect overexpressed AXIN1-295aa. Right: AXIN1 antibody that can recognize the N-terminus of AXIN1 detected both full-length AXIN1 as well as endogenous and overexpressed AXIN1-295aa. e Full-length AXIN1 and AXIN1-295aa are detected in GC cell lines by an anti-AXIN1 N-terminus antibody (CST). f Full-length AXIN1 is detected using an anti-C-terminus antibody and AXIN1-295aa is detected using an anti-N-terminus antibody (US Biological), respectively, in GC cell lines