Key result
Tetrameric IP3R requires IP3 binding at all four sites to open and release calcium.
Why the study?
The requirement that all four IP3-binding sites within the tetrameric IP3R must bind IP3 before channel opening was not fully understood, impacting knowledge of IP3 and IP3R activity distribution within cells.
The finding that all four IP3-binding sites must be occupied for IP3R channel opening has important implications for understanding intracellular calcium signaling.
Informs Ca2+ handling models in cardiomyocytes; extends structural understanding of IP3R gating for further study.
Inositol 1,4,5-trisphosphate receptors (IP3Rs) and ryanodine receptors are the channels responsible for Ca(2+)release from the endoplasmic and sarcoplasmic reticulum. Research inScience Signalingby Alzayadyet al show that all four IP3-binding sites within the tetrameric IP3R must bind IP3before the channel can open, which has important consequences for the distribution of both IP3and IP3R activity within cells.
No takes yet. Share an insight, caveat, or question.
Taylor et al. (2016) reported an editorial. IP3 binding was evaluated. All four IP3-binding sites within the tetrameric IP3R must bind IP3 before the channel can open, impacting the distribution of IP3 and IP3R activity within cells.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: