TY - JOUR
T1 - Structural mechanism underlying G protein family-specific regulation of G protein-gated inwardly rectifying potassium channel
AU - Kano, Hanaho
AU - Toyama, Yuki
AU - Imai, Shunsuke
AU - Iwahashi, Yuta
AU - Mase, Yoko
AU - Yokogawa, Mariko
AU - Osawa, Masanori
AU - Shimada, Ichio
PY - 2019/12/1
Y1 - 2019/12/1
N2 - G protein-gated inwardly rectifying potassium channel (GIRK) plays a key role in regulating neurotransmission. GIRK is opened by the direct binding of the G protein βγ subunit (Gβγ), which is released from the heterotrimeric G protein (Gαβγ) upon the activation of G protein-coupled receptors (GPCRs). GIRK contributes to precise cellular responses by specifically and efficiently responding to the Gi/o-coupled GPCRs. However, the detailed mechanisms underlying this family-specific and efficient activation are largely unknown. Here, we investigate the structural mechanism underlying the Gi/o family-specific activation of GIRK, by combining cell-based BRET experiments and NMR analyses in a reconstituted membrane environment. We show that the interaction formed by the αA helix of Gαi/o mediates the formation of the Gαi/oβγ-GIRK complex, which is responsible for the family-specific activation of GIRK. We also present a model structure of the Gαi/oβγ-GIRK complex, which provides the molecular basis underlying the specific and efficient regulation of GIRK.
AB - G protein-gated inwardly rectifying potassium channel (GIRK) plays a key role in regulating neurotransmission. GIRK is opened by the direct binding of the G protein βγ subunit (Gβγ), which is released from the heterotrimeric G protein (Gαβγ) upon the activation of G protein-coupled receptors (GPCRs). GIRK contributes to precise cellular responses by specifically and efficiently responding to the Gi/o-coupled GPCRs. However, the detailed mechanisms underlying this family-specific and efficient activation are largely unknown. Here, we investigate the structural mechanism underlying the Gi/o family-specific activation of GIRK, by combining cell-based BRET experiments and NMR analyses in a reconstituted membrane environment. We show that the interaction formed by the αA helix of Gαi/o mediates the formation of the Gαi/oβγ-GIRK complex, which is responsible for the family-specific activation of GIRK. We also present a model structure of the Gαi/oβγ-GIRK complex, which provides the molecular basis underlying the specific and efficient regulation of GIRK.
UR - http://www.scopus.com/inward/record.url?scp=85065195153&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85065195153&partnerID=8YFLogxK
U2 - 10.1038/s41467-019-10038-x
DO - 10.1038/s41467-019-10038-x
M3 - Article
C2 - 31043612
AN - SCOPUS:85065195153
VL - 10
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
IS - 1
M1 - 2008
ER -