PMID- 23711249
OWN - NLM
STAT- MEDLINE
DCOM- 20131031
LR  - 20161125
IS  - 1471-4159 (Electronic)
IS  - 0022-3042 (Linking)
VI  - 126
IP  - 6
DP  - 2013 Sep
TI  - Native STIM2 and ORAI1 proteins form a calcium-sensitive and 
      thapsigargin-insensitive complex in cortical neurons.
PG  - 727-38
LID - 10.1111/jnc.12320 [doi]
AB  - In non-excitatory cells, stromal interaction molecule 1 (STIM1) and STIM2 mediate 
      store-operated calcium entry via an interaction with ORAI1 calcium channels. 
      However, in neurons, STIM2 over-expression appears to play a role in calcium 
      homeostasis that is different from STIM1 over-expression. The aim of this study 
      was to establish the role and localization of native STIM2 in the neuronal cell. 
      Co-immunoprecipitation experiments revealed that the interaction between 
      endogenous STIM2 and ORAI1 was greater in a low-calcium medium than in a 
      high-calcium medium. Using a Proximity Ligation Assay (PLA), the number of 
      apparent complexes of endogenous STIM2 with ORAI1 was quantified. No change in 
      the number of PLA signals was observed in the presence of thapsigargin, which 
      depletes calcium from the endoplasmic reticulum (ER). However, the number of 
      apparent STIM2-ORAI1 complexes increased when intracellular and subsequently ER 
      calcium concentrations were decreased by BAPTA-AM or a low-calcium medium. Both 
      Fura-2 acetoxymethyl ester calcium imaging and PLA in the same neuronal cell 
      indicated that the calcium responses correlated strongly with the number of 
      endogenous STIM2-ORAI1 complexes. The small drop in calcium levels in the ER 
      caused by decreased intracellular calcium levels appeared to initiate the 
      calcium-sensitive and thapsigargin-insensitive interaction between STIM2 and 
      ORAI1. We show in neuronal somata the formation of endogenous complexes of 
      stromal interaction molecule 2 (STIM2) with ORAI1 calcium channels. Their number 
      increased when intracellular Ca(2)(+) concentrations were decreased by the Ca(2)(+) 
      chelator BAPTA-AM or a low-calcium medium (EGTA), but did not in the presence of 
      thapsigargin (TG). We conclude that the small drop of Ca(2)(+) level in endoplasmic 
      reticulum, due to the decreased level of intracellular Ca(2)(+), is sufficient to 
      trigger STIM2-ORAI1 complex formation in a thapsigargin-insensitive manner.
CI  - (c) 2013 International Society for Neurochemistry.
FAU - Gruszczynska-Biegala, Joanna
AU  - Gruszczynska-Biegala J
AD  - Laboratory of Neurodegeneration, International Institute of Molecular and Cell 
      Biology, Warsaw, Poland.
FAU - Kuznicki, Jacek
AU  - Kuznicki J
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20130612
PL  - England
TA  - J Neurochem
JT  - Journal of neurochemistry
JID - 2985190R
RN  - 0 (Calcium Channels)
RN  - 0 (Calcium-Binding Proteins)
RN  - 0 (Chelating Agents)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Membrane Proteins)
RN  - 0 (ORAI1 Protein)
RN  - 0 (Orai1 protein, rat)
RN  - 0 (STIM2 protein, rat)
RN  - 0 (Stromal Interaction Molecule 2)
RN  - 139890-68-9 (1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid 
      acetoxymethyl ester)
RN  - 526U7A2651 (Egtazic Acid)
RN  - 67526-95-8 (Thapsigargin)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Animals
MH  - Blotting, Western
MH  - Calcium/*pharmacology
MH  - Calcium Channels/*metabolism
MH  - Calcium-Binding Proteins/*metabolism
MH  - Cells, Cultured
MH  - Cerebral Cortex/cytology/drug effects/*metabolism
MH  - Chelating Agents/pharmacology
MH  - Egtazic Acid/analogs & derivatives/pharmacology
MH  - Endoplasmic Reticulum/drug effects/metabolism
MH  - Enzyme Inhibitors/*pharmacology
MH  - Female
MH  - Image Processing, Computer-Assisted
MH  - Immunoprecipitation
MH  - Membrane Proteins/*metabolism
MH  - Microscopy, Fluorescence
MH  - Neurons/drug effects/*metabolism
MH  - ORAI1 Protein
MH  - Pregnancy
MH  - Rats
MH  - Rats, Wistar
MH  - Stromal Interaction Molecule 2
MH  - Thapsigargin/*pharmacology
OTO - NOTNLM
OT  - ORAI1
OT  - STIM2
OT  - calcium signaling
OT  - neurons
OT  - proximity ligation assay
OT  - store-operated calcium entry
EDAT- 2013/05/29 06:00
MHDA- 2013/11/01 06:00
CRDT- 2013/05/29 06:00
PHST- 2012/12/18 00:00 [received]
PHST- 2013/04/30 00:00 [revised]
PHST- 2013/05/17 00:00 [accepted]
PHST- 2013/05/29 06:00 [entrez]
PHST- 2013/05/29 06:00 [pubmed]
PHST- 2013/11/01 06:00 [medline]
AID - 10.1111/jnc.12320 [doi]
PST - ppublish
SO  - J Neurochem. 2013 Sep;126(6):727-38. doi: 10.1111/jnc.12320. Epub 2013 Jun 12.