WAS Protein Homolog Associated With Actin, Golgi Membranes And Microtubules (WHAMM)

Human WHDC1 expressed in insect cells had an apparent molecular mass of about 100 kD by SDS-PAGE. Western blot analysis detected WHDC1 in most human and mouse organs examined, with highest expression in brain. WHDC1 was also expressed in all cultured cell lines tested. WHDC1 partitioned predominantly in the membrane fraction of COS-7 cells, and it appeared to be a peripheral membrane protein, since high salt or alkaline pH released it into the soluble fraction. Immunohistochemical analysis localized WHDC1 primarily to the perinuclear compartment, near the microtubule-organizing center. In some cells, it also localized to tubulovesicular structures in the cell periphery. WHDC1 colocalized extensively with the cis-Golgi marker GM130 (GOLGA2), but not with medial- or trans-Golgi markers.