RT Journal Article
SR Electronic
T1 β-Arrestin–Biased Agonism of the Angiotensin Receptor Induced by Mechanical Stress
JF Science Signaling
JO Sci. Signal.
FD American Association for the Advancement of Science
SP ra46
OP ra46
DO 10.1126/scisignal.2000769
VO 3
IS 125
A1 Rakesh, Kriti
A1 Yoo, ByungSu
A1 Kim, Il-Man
A1 Salazar, Natasha
A1 Kim, Ki-Seok
A1 Rockman, Howard A.
YR 2010
UL http://stke.sciencemag.org/content/3/125/ra46.abstract
AB β-Arrestins, which were originally characterized as terminators of heterotrimeric guanine nucleotide–binding protein (G protein)–coupled receptor (GPCR) signaling, also act as important signal transducers. An emerging concept in GPCR signaling is β-arrestin–biased agonism, in which specific ligand-activated GPCR conformational states selectively signal through β-arrestins, rather than through G proteins. Here, we show that mechanical stretch induced β-arrestin–biased signaling downstream of angiotensin II type I receptors (AT1Rs) in the absence of ligand or G protein activation. Mechanical stretch triggered an AT1R-mediated conformational change in β-arrestin similar to that induced by a β-arrestin–biased ligand to selectively stimulate receptor signaling in the absence of detectable G protein activation. Hearts from mice lacking β-arrestin or AT1Rs failed to induce responses to mechanical stretch, as shown by blunted extracellular signal–regulated kinase and Akt activation, impaired transactivation of the epidermal growth factor receptor, and enhanced myocyte apoptosis. These data show that the heart responds to acute increases in mechanical stress by activating β-arrestin–mediated cell survival signals.