(A) IPs by anti-Flag antibody from cytosolic fractions of HEK293T cells transfected with Xp-STRAD and the indicated Flag-LKB1 were subjected to IB.
(B) IPs by anti-LKB1 antibody from cytosolic fractions of LKB1-deficient HeLa cells with stable reconstitution of the indicated Flag-LKB1 were subjected to IB.
(C) IPs by anti-IgG control or anti-LKB1 antibody from cytosolic fractions of HEK293T cells with control, Skp2, Ubc13 or MO25 knockdown were subjected IB.
(D) IPs by anti-Flag antibody from Hep3B cells with stable transduction of vector or Skp2 along with the indicated Flag-LKB1 were subjected to IB. The ratio of MO25-LKB1 binding is shown.
See also Figure S4.