Fig. 3: CASK-Mint1 interaction facilitates CASK/Mint1/Munc18-1 complex formation.
From: CASK modulates the assembly and function of the Mint1/Munc18-1 complex to regulate insulin secretion
a Co-immunoprecipitation of overexpressed CASK-GFP, Mint1-Flag and Munc18-1 in 293 cells showed by western blot analysis. Immunoprecipitations (IPs) of CASK and Mint1 were carried out with anti-GFP or anti-FLAG ABs., respectively. b Munc18-1 bound to Mint1-MID-CID directly, but not to CASK-CaMK. Recombinant his-Munc18-1 was incubated with different fusion proteins of GST-CaMK (CASK), CST-Mint1-CID and GST-Mint1-MID-CID (lower panel) as indicated. Upper panel, his-Munc18-1 detected by western blot with anti-his AB. Lower panel, different GST-fusion proteins detected by WB with anti-GST AB. c Co-immunoprecipitation of exogenous CASK, Mint1-Flag and Munc18-1 with anti-flag antibodies when CASK was expressed at different levels in 293 cells. For a and c, anti-tag antibodies were used to detect the proteins co-immunoprecipitated with CASK or Mint1. d The effect of CASK-depletion on the formation of CASK/Mint1/Munc18-1 tripartite complex in native INS-1E cells stimulated with glucose. Left panel, western bolt analysis for detection of the formation of CASK/Mint1/Munc18-1 complex precipitated by IPs with CASK, Mint1 and Munc18 antibodies. Right panel, expression of CASK, Mint1 and Munc18 revealed by western bolt analysis. Ri-1: CASK-specific siRNA; NC: non-silencing control siRNA.
