References
PMID:9113980
RhoGDI (so-called ARHGDIA) and GDIG4 (so-called ARHGDIB) are two known GDIs for the Rho-subfamily of GTPases.
ARHGDIG is about 50 percent identical to ARHGDIA and ARHGDIB. ARHGFIG binds to CDC42 and RhoA with less affinity compared with ARHGDIA and does not bind with Rac1, Rac2, or Ras.
ARHGDIG functions as a GDI for CDC42 but with about 20 times less efficiency than ARHGDIA.
PMID:9490022
ARHGDIA,B,G are CDC42_GDIs