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The endoplasmic reticulum: one continuous or several separate Ca(2+) stores?

O H Petersen·A Tepikin·M K Park
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Abstract

The Ca2+ store and sink in the endoplasmic reticulum (ER) is important for Ca2+ signal integration and for conveyance of information in spatial and temporal domains. Textbooks regard the ER as one continuous network, but biochemical and biophysical studies revealed apparently discrete ER Ca2+ stores. Recent direct studies of ER lumenal Ca2+ movements show that this organelle system is one continuous Ca2+ store, which can function as a Ca2+ tunnel. The concept of a fully connected ER network is entirely compatible with evidence indicating that the distribution of Ca2+ -release channels in the ER membrane is discontinuous with clustering in certain localities.

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CalciumCell CompartmentationEndoplasmic ReticulumJournal ArticleResearch Support, Non-U.S. Gov'tReview

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O H Petersen, A Tepikin, M K Park. 2001. The endoplasmic reticulum: one continuous or several separate Ca(2+) stores?. https://doi.org/10.1016/s0166-2236(00)01787-2

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