A method to map spatiotemporal pH changes in a multicellular living organism using a DNA nanosensor

Cells maintain internal pH to support normal functions. pH affects biomolecule structure and activity. Prior pH probes have limitations in sensitivity or specificity. Researchers need tools to track pH changes in living organisms. Some probes lack dynamic range or stability. Others cannot distinguish between organelles. This gap motivated the development of a new DNA-based nanosensor. The sensor must operate in complex multicellular environments. The study introduces a DNA nanomachine for pH mapping in C. elegans.

The aim is to develop a pH-sensing tool for in vivo use in multicellular organisms. The tool must detect pH changes in real time and in specific cellular compartments. The tool should function across different genetic backgrounds. The method must be stable and sensitive in physiological pH ranges. The tool should be compatible with fluorescent detection techniques. The method should allow comparison between wild-type and mutant organisms. The goal is to enable detailed pH mapping during cellular processes like endocytosis. The tool should be adaptable for various biological investigations.

The method uses a DNA nanomachine introduced externally into C. elegans. The nanomachine is pH-sensitive and employs FRET for detection. The device is tested in coelomocytes of wild-type and mutant worms. The pH range of interest is 5.3–6.6, typical for intracellular compartments. The nanomachine's dynamic range is measured in this range. The half-life of the device is approximately 8 hours in vivo. The method allows tracking of pH changes during endocytosis. The tool is used across multiple genetic backgrounds to assess variability.

The DNA nanomachine successfully maps pH changes in coelomocytes of C. elegans. The device has a dynamic range of pH 5.3–6.6, covering relevant physiological conditions. The nanomachine's half-life is ~8 hours, suitable for long-term in vivo studies. The tool detects pH fluctuations during endocytosis in wild-type worms. The device also functions in mutant strains with altered pH regulation. The FRET signal provides spatial and temporal resolution of pH changes. The method is effective across multiple genetic backgrounds. The results suggest the tool can be used for various pH-dependent biological processes.

The DNA nanomachine effectively maps intracellular pH changes in a multicellular organism. The device operates in the pH range 5.3–6.6 with a half-life of ~8 hours. The tool is suitable for studying pH-dependent processes like endocytosis. The method works in both wild-type and mutant C. elegans. The device provides spatiotemporal resolution of pH changes. The tool is stable and sensitive for in vivo applications. The results suggest potential for broader use in pH-related biological investigations. The study demonstrates the nanomachine's utility in a complex multicellular system.