STIM2

Description

The STIM2 (stromal interaction molecule 2) is a protein-coding gene located on chromosome 4.

STIM2, short for Stromal Interaction Molecule 2, is a protein that is encoded by the STIM2 gene in humans. It belongs to a family of two proteins, STIM1 and STIM2, that are involved in regulating calcium levels within cells. STIM2, like STIM1, is a type 1 transmembrane protein located in the endoplasmic reticulum (ER), a network of internal membranes within cells. Alternative ways of starting protein production from this gene lead to the creation of two slightly different versions of the STIM2 protein.

STIM2, along with STIM1, is a calcium sensor, meaning it detects changes in calcium concentrations. Specifically, it helps regulate the process of store-operated calcium entry (SOCE), a mechanism that allows cells to replenish their internal calcium stores. SOCE is essential for many cellular processes, as it provides a continuous supply of calcium, a key signaling molecule in cells. Although STIM1 is the primary trigger for SOCE, STIM2 is believed to play a crucial role as a feedback regulator, helping to stabilize calcium levels within the cell and the ER.

STIM2 is particularly sensitive to small changes in ER calcium levels. When these levels decrease, STIM2 changes its conformation (shape) and interacts with channels in the cell membrane called store-operated calcium (SOC) channels, such as ORAI channels. This interaction allows calcium to flow back into the cell, restoring the balance of calcium levels.

While the specific function of STIM2 was unclear for a while, research conducted using animal models between 2009 and 2010 revealed its involvement in various cellular processes, including the development and function of smooth muscle cells, immune cells, and neurons. Additionally, STIM2 has been implicated in tumor development, autoimmune diseases, and the mechanisms of neuronal damage after temporary blood flow disruptions.

STIM2 was discovered in 2001 as a close relative of STIM1, representing the second member of this gene family found in vertebrates.

STIM2 plays a role in regulating calcium levels within cells, specifically in the process of store-operated calcium entry (SOCE). SOCE is a mechanism where calcium ions (Ca2+) are brought into the cell from outside after the cell's internal calcium stores are depleted. STIM2 acts as a sensitive sensor for changes in calcium levels within the endoplasmic reticulum (ER), a major intracellular calcium storage organelle. When calcium levels in the ER decrease, STIM2 triggers the opening of calcium channels located in the cell membrane, allowing calcium to flow back into the cell. This process helps maintain a stable calcium balance. STIM2 also interacts with other calcium channels in the cell membrane, including ORAI1, ORAI2, and ORAI3. It can potentially suppress the activity of STIM1, another protein involved in SOCE.

STIM2 is also known as -.

Associated Diseases

WES Whole Exome Sequencing

Clinical Exome Sequencing