Search Results

Astrocytes are non-excitable cells in the brain and their activity largely depends on the intracellular calcium (Ca²⁺) level. Therefore, maintaining the intracellular Ca²⁺ homeostasis is critical for proper functioning of astrocytes. One of the key regulatory mechanisms of Ca²⁺ homeostasis in astrocytes is the store-operated Ca²⁺ entry (SOCE). This process is mediated by a combination of the Ca²⁺-store-depletion-sensor, Stim, and the store-operated Ca²⁺-channels, Orai and TrpC families. Despite the existence of all those families in astrocytes, previous studies have provided conflicting results on the molecular identification of astrocytic SOCE. Here, using the shRNA-based gene-silencing approach and Ca²⁺-imaging from cultured mouse astrocytes, we report that Stim1 in combination with Orai1 and Orai3 contribute to the major portion of astrocytic SOCE. Gene-silencing of Stim1 showed a 79.2% reduction of SOCE, indicating that Stim1 is the major Ca²⁺-store-depletion-sensor. Further gene-silencing showed that Orai1, Orai2, Orai3, and TrpC1 contribute to SOCE by 35.7%, 20.3%, 26.8% and 12.2%, respectively. Simultaneous gene-silencing of all three Orai subtypes exhibited a 67.6% reduction of SOCE. Based on the detailed population analysis, we predict that Orai1 and Orai3 are expressed in astrocytes with a large SOCE, whereas TrpC1 is exclusively expressed in astrocytes with a small SOCE. This analytical approach allows us to identify the store operated channel (SOC) subtype in each cell by the degree of SOCE. Our results propose that Stim1 in combination with Orai1 and Orai3 are the major molecular components of astrocytic SOCE under various physiological and pathological conditions.
Animals ; Astrocytes* ; Brain ; Calcium* ; Homeostasis ; Humans ; Mice

1.Up to Date on Astrocytes.

2.Establishment of a Culture Method and Characterization for Human Fetal Astrocytes.

3.Identification of Differentially Expressed Genes in Human Fetal Astrocytes.

4.Monitoring the Activity of Astrocytes in Learning and Memory.

5.Bacterial Lipopolysaccharide - Induced Generation of Nitric Oxide is Mediated by ERK1 and JNK1 / SAPK in Primary Rat Neonatal Astrocytes.

6.Scavenger receptor on astrocytes and its relationship with neuroinflammation.

7.Orai1 and Orai3 in Combination with Stim1 Mediate the Majority of Store-operated Calcium Entry in Astrocytes.

8.Characterization of Gene Expression Pattern in Human Astrocytes using DDRT - PCR Method.

9.Role of astrocyte in pathogenesis of epilepsy.

10.Astrocyte-Mediated Myelin Phagocytosis in Ischemia.

Display Mode

Output Records

File Type