Header menu link for other important links
X
A G-protein subunit translocation embedded network motif underlies GPCR regulation of calcium oscillations
, A.K. Patel, W.K.A. Karunarathne, V. Kalyanaraman, K.V. Venkatesh, N. Gautam
Published in Biophysical Society
2014
PMID: 24988358
Volume: 107
   
Issue: 1
Pages: 242 - 254
Abstract
G-protein βγ subunits translocate reversibly from the plasma membrane to internal membranes on receptor activation. Translocation rates differ depending on the γ subunit type. There is limited understanding of the role of the differential rates of Gβγ translocation in modulating signaling dynamics in a cell. Bifurcation analysis of the calcium oscillatory network structure predicts that the translocation rate of a signaling protein can regulate the damping of system oscillation. Here, we examined whether the Gβγ translocation rate regulates calcium oscillations induced by G-protein-coupled receptor activation. Oscillations in HeLa cells expressing γ subunit types with different translocation rates were imaged and quantitated. The results show that differential Gβγ translocation rates can underlie the diversity in damping characteristics of calcium oscillations among cells. Mathematical modeling shows that a translocation embedded motif regulates damping of G-protein-mediated calcium oscillations consistent with experimental data. The current study indicates that such a motif may act as a tuning mechanism to design oscillations with varying damping patterns by using intracellular translocation of a signaling component. © 2014 Biophysical Society.
About the journal
JournalBiophysical Journal
PublisherBiophysical Society
ISSN00063495