Ligand-induced endocytosis and nuclear localization of angiotensin II receptors expressed in CHO cells.
A construct (AT1R-NF) containing a "Flag" sequence added to the N-terminus of the rat AT1 receptor was stably expressed in Chinese hamster ovary cells and quantified in the cell membrane by confocal microscopy after reaction with a fluorescein-labeled anti-Flag monoclonal antibody. Angiotensin II bound to AT1R-NF and induced endocytosis with a half-time of 2 min. After 60-90 min, fluorescence accumulated around the cell nucleus, suggesting migration of the ligand-receptor complex to the nuclear membrane. Angiotensin antagonists also induced endocytosis, suggesting that a common step in the transduction signal mechanism occurring after ligand binding may be responsible for the ligand-receptor complex internalization.
Merjan
A J
AJ
Departamento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
Kanashiro
C A
CA
Krieger
J E
JE
Han
S W
SW
Paiva
A C
AC
D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000502:physiology*; D057911:Angiotensin Receptor Antagonists; D000818:Animals; D015152:Blotting, Northern; D016466:CHO Cells / Q000378:metabolism*; D002462:Cell Membrane; D006224:Cricetinae; D004705:Endocytosis / Q000502:physiology; D008024:Ligands; D018613:Microscopy, Confocal; D009685:Nuclear Envelope / Q000378:metabolism*; D051381:Rats; D011945:Receptors, Angiotensin / Q000378:metabolism* / Q000502:physiology; D015398:Signal Transduction; D014162:Transfection
D057911:Angiotensin Receptor Antagonists; D008024:Ligands; D011945:Receptors, Angiotensin; D000804:Angiotensin II