Appears to be a negative regulator of type-1 angiotensin II receptor-mediated signaling by regulating receptor internalization as well as mechanism of receptor desensitization such as phosphorylation. Induces also a decrease in angiotensin II-stimulated transcriptional activity. May play a role of negative regulator in cardiomyocyte hypertrophy induced by angiotensin II through an inhibition of p38 mitogen-activated protein kinase pathway. Interacts with RACK1 (By similarity), and with the C-terminal region of AGTR1. Present in perinuclear vesicular membranes, Endoplasmic reticulum, Golgi and endocytic vesicles. Ubiquitous but more abundant in kidney, testis and heart.