Identification of a STIM1 Splicing Variant that Promotes Glioblastoma Growth.

Deregulated store-operated calcium entry (SOCE) mediated by aberrant STIM1-ORAI1 signaling is closely implicated in cancer initiation and progression. Here the authors report the identification of an alternatively spliced variant of STIM1, designated STIM1β, that harbors an extra exon to encode 31 additional amino acids in the cytoplasmic domain. STIM1β, highly conserved in mammals, is aberrantly upregulated in glioma tissues to perturb Ca signaling.

Bidirectional role of microtubule dynamics in the acquisition and maintenance of temporal information in dorsolateral striatum.

Accurate and precise timing is crucial for complex and purposeful behaviors, such as foraging for food or playing a musical instrument. The brain is capable of processing temporal information in a coordinated manner, as if it contains an 'internal clock'. Similar to the need for the brain to orient itself in space in order to understand its surroundings, temporal orientation and tracking is an essential component of cognition as well.

Store-Operated Calcium Entry Mediated by ORAI and STIM.

The calcium release-activated calcium (CRAC) channel, composed of ORAI and stromal interaction molecules (STIM), represents a prototypical example of store-operated calcium entry in mammals. The ORAI-STIM signaling occurs at membrane contact sites formed by close appositions between the endoplasmic reticulum (ER) and the plasma membrane. ORAI1 is a four-pass transmembrane protein that forms a highly calcium-selective ion channel in the plasma membrane.

The STIM-Orai Pathway: Light-Operated Ca Entry Through Engineered CRAC Channels.

Ca signals regulate a plethora of cellular functions that include muscle contraction, heart beating, hormone secretion, lymphocyte activation, gene expression, and metabolism. To study the impact of Ca signals on biological processes, pharmacological tools and caged compounds have been commonly applied to induce fluctuations of intracellular Ca concentrations. These conventional approaches, nonetheless, lack rapid reversibility and high spatiotemporal resolution.

Optogenetic toolkit for precise control of calcium signaling.

Calcium acts as a second messenger to regulate a myriad of cell functions, ranging from short-term muscle contraction and cell motility to long-term changes in gene expression and metabolism. To study the impact of Ca-modulated 'ON' and 'OFF' reactions in mammalian cells, pharmacological tools and 'caged' compounds are commonly used under various experimental conditions. The use of these reagents for precise control of Ca signals, nonetheless, is impeded by lack of reversibility and specificity.