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Dissection of Local Ca2+ Signals in Cultured Cells by Membrane-targeted Ca2+ Indicators
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Dissection of Local Ca2+ Signals in Cultured Cells by Membrane-targeted Ca2+ Indicators

Published on: March 22, 2019

CBL-mediated targeting of CIPKs facilitates the decoding of calcium signals emanating from distinct cellular stores

Oliver Batistic1, Rainer Waadt, Leonie Steinhorst

  • 1Institut für Botanik, Universität Münster, Schlossplatz 4, 48149 Münster, Germany.

The Plant Journal : for Cell and Molecular Biology
|October 17, 2009
PubMed

Insights

Plant cells use Calcineurin B-like (CBL) proteins and CBL-interacting protein kinases (CIPKs) to decode calcium signals. This study reveals how CBL proteins target specific cellular locations, ensuring precise calcium signal processing for cellular responses.

Area of Science:

  • Plant molecular biology
  • Cellular signaling networks
  • Calcium homeostasis

Background:

  • Cells utilize complex calcium-decoding signaling cascades for adaptation and development.
  • The molecular basis for specificity in cellular responses mediated by calcium signaling remains unclear.
  • Calcineurin B-like (CBL) proteins are key players in calcium signal decoding through interactions with CBL-interacting protein kinases (CIPKs).

Purpose of the Study:

  • To determine the subcellular localization of all 10 Arabidopsis CBL proteins.
  • To construct a cellular localization matrix for the plant calcium signaling network.
  • To elucidate the mechanisms underlying the specificity of cellular responses to calcium signals.

Main Methods:

  • Comprehensive analysis of the subcellular localization of all 10 CBL proteins in Arabidopsis.
  • Development of a cellular localization matrix for plant calcium signaling components.
  • Identification of targeting signals within CBL proteins responsible for their localization.

Main Results:

  • All 10 Arabidopsis CBL proteins exhibit diverse subcellular localizations, including plasma membrane, tonoplast, cytoplasm, and nucleus.
  • Distinct N-terminal targeting signals dictate the spatially discrete localization of CBL/CIPK complexes.
  • COPII-independent pathways are involved in the targeting of CBL proteins.

Conclusions:

  • The CBL/CIPK signaling network functions as a sophisticated calcium decoding system.
  • This network enables simultaneous and specific processing of calcium signals from various intracellular and extracellular stores.
  • The findings provide a molecular mechanism for the specificity observed in cellular responses to calcium signals.

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