Mutual exclusion of Atg4 or Atg3 with p62 in LC3 complex.

HEK293 cells were co-transfected with mRFP-p62/GFP-Atg3/Flag-LC3 or mRFP-p62/GFP-Atg4B/Flag-LC3 for 48 h. Total cell lysates were used to conduct IP using correspondent antibodies. Immunoblottings were then applied using antibodies as indicated (A and B). HEK293 cells were transfected with GFP-Atg4B or GFP-Atg4B^C74A alone or with mRFP-p62 for 48 h (C). HEK293 cells were transfected with GFP-Atg3 alone or with mRFP-p62 for 48 h (D). Total cell lysates were used to detect LC3 species as indicated. Relative band intensity of protein of interest was divided by correspondent band intensity of β-actin loading control. Fold of increase or decrease was then determined by setting the control sample as 1.