Measuring SERCA-mediated calcium uptake in mouse muscle homogenates

Area of Science:

• Biochemistry
• Molecular Biology
• Physiology

Background:

• The sarco(endo)plasmic reticulum Ca²⁺ ATPase (SERCA) pump is crucial for muscle contraction and relaxation.
• Accurate quantification of Ca²⁺ uptake is essential for understanding muscle function and disease.
• Existing methods may have limitations in real-time kinetic measurements or sample requirements.

Purpose of the Study:

• To present a robust protocol for quantifying Ca²⁺ uptake by the SERCA pump in murine muscle homogenates.
• To enable real-time kinetic measurement of Ca²⁺ mobilization.
• To provide an adaptable assay suitable for various tissues and Ca²⁺ dyes.

Main Methods:

• Employing the indo-1 Ca²⁺ fluorophore for sensitive Ca²⁺ detection.
• Utilizing murine muscle homogenates for assay preparation.
• Adapting the protocol for a 96-well plate format for high-throughput analysis.

Main Results:

• The protocol successfully quantifies Ca²⁺ uptake by the SERCA pump.
• Real-time kinetic measurements of Ca²⁺ mobilization are achievable.
• The assay demonstrates adaptability to different tissue types and Ca²⁺ dyes.

Conclusions:

• This protocol offers a reliable and efficient method for studying SERCA pump activity.
• The assay's adaptability and minimal sample requirement make it accessible for widespread laboratory use.
• The real-time kinetic measurement capability provides valuable insights into muscle Ca²⁺ dynamics.