CalDAG-GEFs are required for PI3Kγ-mediated Rap1 and integrin α4β1 activation in myeloid cells.

<p>(A) Adhesion of chemoattractant-treated CD11b+ myeloid cells to VCAM-1 after transfection with non-silencing, CalDAG-GEFI, CalDAG-GEFII, Epac1, Epac2 and CalDAG-GEFI+CalDAG-GEFII siRNAs (n = 3), *P<0.01, CalDAG-GEFI, CalDAG-GEFII vs non silencing siRNA. (B) Adhesion to VCAM-1 of myeloid cells after transfection with CalDAG-GEFI and II or control siRNAs in combination with pRapV12, p110γCAAX, or empty plasmid (n = 3), *P<0.01 CalDAG-GEFI and II vs control siRNAs. (C) Rap1 GTP and total Rap immunoblot of unstimulated, non-silencing siRNA-transfected (Basal) myeloid cells and SDF-1α stimulated CalDAG-GEFI and II, Epac 1 and 2, and non-silencing siRNA-transfected myeloid cells. (D) Rap1 GTP and total Rap immunoblot of unstimulated non-silencing siRNA-transfected (basal) and SDF-1α-stimulated myeloid cells after transfection with PLCγ1 or control siRNA. (E) Adhesion of PLCγ1 or control siRNA-transfected, chemoattractant-stimulated myeloid cells (n = 3), *P<0.01 PLCγ1 vs non-silencing siRNA. (F) Adhesion to VCAM-1 of myeloid cells after transfection with PLCγ1 or control siRNA in combination with pRapV12, p110γCAAX, or vector control (empty plasmid) (n = 3), *P<0.01 vs PLCγ1 non-silencing siRNA.