Intracellular Ca2+-uptake and its contribution to signalling

钙是真核细胞中最常见的第二信使，通常认为Ca2+信号的特异性可以通过刺激特异性、时空不同的细胞质Ca2+浓度变化来实现。这些Ca2+信号响应于不同的刺激是通道和转运体的组合和严格调节的活动的结果，这些通道和转运体介导细胞质内Ca2+的分泌和外排。我们的目标是了解个体细胞内Ca2+储存和运输系统如何促进[Ca2+]细胞瞬态的时空特征。我们已经添加了所谓的geco，这是一种新型的基于强度的Ca2+传感器，具有非常高的动态范围，可以在工具箱中使用不同的颜色，现在能够生成根中局部和系统Ca2+响应的高分辨率图谱。我们特别关注的将是确定空泡钙的释放是否以及如何有助于Ca2+信号。通过光谱上不同的GECOs的组合表达，我们将能够同时测量不同腔室中的Ca2+动力学，并通过将GECOs与ROS和pH传感器结合，我们计划阐明这些重要信号分子之间的时空关系。此外，通过细胞类型特异性和诱导表达钙诱饵，我们计划干扰局部和全身Ca2+反应。

Calcium is the most common second messenger in eukaryotic cells and it is generally assumed that specificity in Ca2+ signalling can be achieved by stimulus-specific, spatio-temporally distinct changes in cytosolic Ca2+ concentrations. Such Ca2+ signatures in response to different stimuli are the result of the combined and tightly regulated activities of channels and transporters that mediatein- and efflux of cytosolic Ca2+. Our objective is to understand how individual intracellular Ca2+-stores and transport systems contribute to the spatial and temporal characteristics of [Ca2+]cyttransients. We have added the so-called GECOs, a novel class of intensity based Ca2+ sensors with a very high dynamic range and available in different colours to the toolbox and are now able to generate a high-resolution atlas of both local and systemic Ca2+-responses in roots. Our particular focus will be to determine if and how release of vacuolar calcium contributes to Ca2+-signatures. By combinatorial expression of spectrally distinct GECOs we will be able to simultaneously measure Ca2+-dynamics in different compartments and by combining GECOs with sensors for ROS and pH we plan to elucidate the temporal and spatial relationships among these important signalling molecules. Furthermore, by cell-type specific and inducible expression of calcium decoys we plan to interfere with local and systemic Ca2+-responses.