Recent studies indicate novel roles for the ubiquitous ion pump, Na,K-ATPase, in addition to its function as a key regulator of intracellular sodium and potassium concentration. We have previously demonstrated that ouabain, the endogenous ligand of Na,K-ATPase, can trigger intracellular Ca²+ oscillations, a versatile intra- cellular signal controlling a diverse range of cellular processes. Here we report that Na,K-ATPase and inosi- tol 1,4,5-trisphosphate (InsP3) receptor (InsP3R) form a cell signaling microdomain that, in the presence of oua- bain, generates slow Ca²+ oscillations in renal cells. Us- ing fluorescent resonance energy transfer (FRET) meas- urements, we detected a close spatial proximity between Na,K-ATPase and InsP3R. Ouabain significantly en- hanced FRET between Na,K-ATPase and InsP R. The FRET effect and ouabain-induced Ca²+ oscillations were not observed following disruption of the actin cytoskel- eton. Partial truncation of the NH₂ terminus of Na,K- ATPase catalytic al-subunit abolished Ca²+ oscillations and downstream activation of NF-kB. Ouabain-induced Ca²+ oscillations occurred in cells expressing an InsP3 sponge and were hence independent of InsP3 generation. Thus, we present a novel principle for a cell signaling microdomain where an ion pump serves as a receptor.
Recent studies indicate novel roles for the ubiquitous ion pump, Na,K-ATPase, in addition to its function as a key regulator of intracellular sodium and potassium concentration. We have previously demonstrated that ouabain, the endogenous ligand of Na,K-ATPase, can trigger intracellular Ca²+ oscillations, a versatile intra- cellular signal controlling a diverse range of cellular processes. Here we report that Na,K-ATPase and inosi- tol 1,4,5-trisphosphate (InsP3) receptor (InsP3R) form a cell signaling microdomain that, in the presence of oua- bain, generates slow Ca²+ oscillations in renal cells. Us- ing fluorescent resonance energy transfer (FRET) meas- urements, we detected a close spatial proximity between Na,K-ATPase and InsP3R. Ouabain significantly en- hanced FRET between Na,K-ATPase and InsP R. The FRET effect and ouabain-induced Ca²+ oscillations were not observed following disruption of the actin cytoskel- eton. Partial truncation of the NH₂ terminus of Na,K- ATPase catalytic al-subunit abolished Ca²+ oscillations and downstream activation of NF-kB. Ouabain-induced Ca²+ oscillations occurred in cells expressing an InsP3 sponge and were hence independent of InsP3 generation. Thus, we present a novel principle for a cell signaling microdomain where an ion pump serves as a receptor.
Biology 2e
2nd Edition
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark
Chapter9: Cell Communication
Section: Chapter Questions
Problem 12RQ: Histamine binds to the H1 G-protein-linked receptor to initiate the itchiness and airway...
Related questions
Question
Can you give a clear explanations of the introduction for this paper? Please explain as if your presenting a group presentation about this paper introduction.
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 3 steps
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Recommended textbooks for you
Biology 2e
Biology
ISBN:
9781947172517
Author:
Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:
OpenStax
Biochemistry
Biochemistry
ISBN:
9781305577206
Author:
Reginald H. Garrett, Charles M. Grisham
Publisher:
Cengage Learning
Human Physiology: From Cells to Systems (MindTap …
Biology
ISBN:
9781285866932
Author:
Lauralee Sherwood
Publisher:
Cengage Learning
Biology 2e
Biology
ISBN:
9781947172517
Author:
Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:
OpenStax
Biochemistry
Biochemistry
ISBN:
9781305577206
Author:
Reginald H. Garrett, Charles M. Grisham
Publisher:
Cengage Learning
Human Physiology: From Cells to Systems (MindTap …
Biology
ISBN:
9781285866932
Author:
Lauralee Sherwood
Publisher:
Cengage Learning