TY - JOUR
T1 - Nuclear pore disassembly from endoplasmic reticulum membranes promotes Ca2+ signalling competency
AU - Boulware, Michael J.
AU - Marchant, Jonathan S.
PY - 2008/6/15
Y1 - 2008/6/15
N2 - The functionality of the endoplasmic reticulum (ER) as a Ca2+ storage organelle is supported by families of Ca2+ pumps, buffers and channels that regulate Ca2+ fluxes between the ER lumen and cytosol. Although many studies have identified heterogeneities in Ca2+ fluxes throughout the ER, the question of how differential functionality of Ca2+ channels is regulated within proximal regions of the same organelle is unresolved. Here, we studied the in vivo dynamics of an ER subdomain known as annulate lamellae (AL), a cytoplasmic nucleoporin-containing organelle widely used in vitro to study the mechanics of nuclear envelope breakdown. We show that nuclear pore complexes (NPCs) within AL suppress local Ca+ signalling activity, an inhibitory influence relieved by heterogeneous dissociation of nucleoporins to yield NPC-denuded ER domains competent at Ca2+ signalling. Consequently, we propose a novel generalized role for AL - reversible attenuation of resident protein activity - such that regulated AL (dis)assembly via a kinase/phosphatase cycle allows cells to support rapid gain/ loss-of-function transitions in cellular physiology.
AB - The functionality of the endoplasmic reticulum (ER) as a Ca2+ storage organelle is supported by families of Ca2+ pumps, buffers and channels that regulate Ca2+ fluxes between the ER lumen and cytosol. Although many studies have identified heterogeneities in Ca2+ fluxes throughout the ER, the question of how differential functionality of Ca2+ channels is regulated within proximal regions of the same organelle is unresolved. Here, we studied the in vivo dynamics of an ER subdomain known as annulate lamellae (AL), a cytoplasmic nucleoporin-containing organelle widely used in vitro to study the mechanics of nuclear envelope breakdown. We show that nuclear pore complexes (NPCs) within AL suppress local Ca+ signalling activity, an inhibitory influence relieved by heterogeneous dissociation of nucleoporins to yield NPC-denuded ER domains competent at Ca2+ signalling. Consequently, we propose a novel generalized role for AL - reversible attenuation of resident protein activity - such that regulated AL (dis)assembly via a kinase/phosphatase cycle allows cells to support rapid gain/ loss-of-function transitions in cellular physiology.
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U2 - 10.1113/jphysiol.2008.153379
DO - 10.1113/jphysiol.2008.153379
M3 - Article
C2 - 18450775
AN - SCOPUS:45249108917
SN - 0022-3751
VL - 586
SP - 2873
EP - 2888
JO - Journal of Physiology
JF - Journal of Physiology
IS - 12
ER -