Calcineurin Signaling and Calcium Homeostasis in Saccharomyces Cerevisiae

In the budding yeast Saccharomyces cerevisiae, intracellular calcium acts as a versatile second messenger coordinating stress responses, ion balance and cell wall integrity. Under resting conditions, free cytosolic calcium is maintained at low nanomolar concentrations by concerted action of calcium pumps and exchangers on the vacuolar and Golgi membranes. Environmental or cellular triggers—including osmotic shock, alkaline stress or mating pheromones—induce transient calcium influx through the Cch1–Mid1 channel complex or release from internal stores via the Yvc1 channel. Calcium ions bind to calmodulin, which in turn activates the serine–threonine phosphatase calcineurin. Calcineurin dephosphorylates the zinc-finger transcription factor Crz1, enabling its nuclear localisation and the coordinated expression of genes essential for ionic homeostasis, cell wall biosynthesis and phosphate transport. Restoration of basal calcium levels is achieved through vacuolar pumps such as Pmc1 and Golgi ATPases including Pmr1, while recently identified antiporters like Gdt1 contribute to fine-tuning Golgi calcium pools. This tightly regulated signalling network underpins yeast adaptability and offers insights into conserved mechanisms across eukaryotes.

Research from Nature Portfolio

A foundational study revealed that the Golgi-localised cation/Ca2+ exchanger Gdt1 is critical for maintaining cellular calcium stores and for modulating the stress-induced calcium signal when the principal Golgi pump is compromised. Functional assays in a heterologous system confirmed Gdt1’s role as a Ca2+/H+ antiporter sensitive to external pH, and genetic analysis in yeast showed that Gdt1 activity is required for proper glycosylation of secretory proteins under high calcium conditions. This work emphasises how specialised transporters in the secretory pathway integrate calcium homeostasis with protein maturation.

Calcineurin Signaling and Calcium Homeostasis in Saccharomyces Cerevisiae publication trend

The graph below shows the total number of articles in calcineurin signaling and calcium homeostasis in saccharomyces cerevisiae across all publications each year (not limited to Nature Index journals).

Technical terms

Calcineurin: A conserved Ca2+/calmodulin-dependent phosphatase that dephosphorylates target proteins to regulate stress-responsive gene expression.

Crz1: A zinc-finger transcription factor activated by calcineurin that controls genes involved in ion homeostasis and cell wall maintenance.

Golgi Ca2+/H+ antiporter (Gdt1): A membrane exchanger that imports calcium into the Golgi lumen in exchange for protons, contributing to secretory pathway function.

High-affinity calcium channel (Cch1–Mid1): A plasma-membrane complex that mediates calcium influx in response to environmental or developmental signals.

References

1. Interaction of calcium responsive proteins and transcriptional factors with the PHO regulon in yeasts and fungi. Frontiers in Cell and Developmental Biology (2023).
2. Overexpression profiling reveals cellular requirements in the context of genetic backgrounds and environments. PLOS Genetics (2023).
3. Yeast Gdt1 is a Golgi-localized calcium transporter required for stress-induced calcium signaling and protein glycosylation. Scientific Reports (2016).