Tx- and H6-tagged full-length RGS14 (1), and truncated versions of the protein which contain the RGS domain (2) (aa1-205, R14-RGS), the RBD region (3) (aa205-490, R14-RBD), the RBD region and an active (4) or inactive GPSM domain (5) (aa299-544, R14-RBD/GPSM, R14-RBD/GPSM(LLAA)), or the wild type (6) or inactivated GPSM domain (7) (aa444-544, R14-GPSM, R14-GPSM(LLAA)). Abbreviations: RGS: regulator of G protein signalling; R1,R2: Ras binding domains 1 and 2. GPSM, G protein signalling modulator.