Previous studies show that angiotensin II (Ang II) increases phosphoinositide turnover in cultured neonatal heart cells. Ang II has also been shown to transiently increase spontaneous beating behavior in these cells. In this study we seek to identify the molecular mechanism underlying this rapid (3-5-minute) desensitization. Time-course studies on the accumulation of [3H]inositol phosphates ind...

Neurons receive information from other neurons via their dendritic tree. Dendrites and their branches result from alternating outgrowth and retraction. The Rho GTPases Rac and Cdc42 (cell division cycle 42) facilitate the outgrowth of branches, whereas Rho attenuates it. The mechanism of neurite retraction is unknown. Because the adenylyl cyclase activator forskolin causes numerous branched ext...

The human IgA Fc receptor (FcalphaR, CD89) triggers several important physiological functions, including phagocytosis, NADPH oxidase activation and antigen presentation. Efforts are underway to delineate FcalphaR signal-transduction pathways that control these functions. In a previous study, we demonstrated that cross-linking of FcalphaR increased its partitioning into membrane glycolipid rafts...