Fig. 6.

RASA3 is mislocalized in scat leading to its loss of function. (A) Western blot analyses on scat peripheral blood show that RASA3 is present in whole red cells (predominantly reticulocytes). (B) By immunofluorescence, RASA3 is mislocalized to the cytosol in scat. (C) Western blot analysis of the red cell membrane ghost fractions confirms the presence of RASA3 on the membrane in WT mice and loss of membrane-bound RASA3 in scat. (D) As a consequence of mislocalization to the cytosol, active GTP-bound active Ras is increased in scat. (E) Consistent with the loss of RASA3 during maturation, active Ras levels are increased in mature red blood cells (RBCs), both in WT and scat as shown by Western blot. (F) Quantitation of the bands demonstrates a higher degree of increase in scat RBCs. X ± SEM; *P < 0.05, t test. (G) Proposed model in which the scat disease during crisis episodes results from RASA3 protein mislocalization leading to loss of its GAP activity.