Dissociation of Heterotrimeric G Proteins in Cells

Correction for Sci. Signal. 1(28):er3

Sci. Signal., 24 June 2008
Vol. 1, Issue 25, p. re5
DOI: 10.1126/scisignal.125re5

Dissociation of Heterotrimeric G Proteins in Cells

  1. Nevin A. Lambert*
  1. Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA 30912–2300, USA.
  1. *Corresponding author. E-mail: nlambert{at}mcg.edu


Heterotrimeric G proteins dissociate into their component Gα and Gβγ subunits when these proteins are activated in solution. Until recently, it has not been known if subunit dissociation also occurs in cells. The development of optical methods to study G protein activation in live cells has made it possible to demonstrate heterotrimer dissociation at the plasma membrane. However, subunit dissociation is far from complete, and many active [guanosine triphosphate (GTP)–bound] heterotrimers are intact in a steady state. This unexpectedly reluctant dissociation calls for inclusion of a GTP-bound heterotrimeric state in models of the G protein cycle and places renewed emphasis on the relation between subunit dissociation and effector activation.


N. A. Lambert, Dissociation of Heterotrimeric G Proteins in Cells. Sci. Signal. 1, re5 (2008).

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