Fig. 5.

The cytoplasmic domain of ADAM10 dimerizes in a cell membrane. (A) Illustration of MBP-AraC constructs used in the study. Construct a10TmCp-DN contains the same ADAM10 residues as in a10TmCp plus a loss-of-function mutation in the AraC domain (AraC*). (B) MalE complementation to test the topology of chimeric proteins. The pMal-p2 and pMal-c2 plasmids express MBP protein in the periplasm and cytoplasm of E. coli, respectively. The positive control construct (pos. contr.) expresses the MBP-AraC chimeric protein containing a tightly dimerizing integrin αIIb transmembrane sequence (28). (C and D) Ratios of GFP fluorescence intensity vs. OD₆₀₀ for each construct are compared with the background (bkgd) and positive control. In the background sample, E. coli was not transformed with the MBP-AraC–expressing vector. (Upper) Comparable expression levels of chimeric MBP-AraC proteins probed by Western blot using the anti-MBP antibody.