mtKeima

mtKeima is a fluorescent protein derived from the coral species Montipora sp. that is widely used in biological research and imaging techniques. It belongs to the family of fluorescent proteins that exhibit pH-dependent fluorescence, making it useful for studying cellular processes such as autophagy, protein trafficking, and pH changes within cells.

The distinctive feature of mtKeima is its ability to switch fluorescence excitation spectra based on pH, while maintaining a consistent emission wavelength. At neutral pH, it is excited optimally at around 440 nm, but in acidic environments, its excitation peaks shift to approximately 560 nm. This property allows researchers to distinguish between different cellular compartments or states based on their pH environment.

Annotated for use in mitochondrial studies, mtKeima can be targeted specifically to mitochondria within cells, enabling visualization of mitochondrial dynamics, health, and mitophagy (mitochondrial autophagy). Its robustness, photostability, and high contrast have made it a popular choice for live-cell imaging and quantitative analysis.

The development of mtKeima was driven by a need for fluorescent markers capable of assessing organelle-specific pH changes with high spatial and temporal resolution. It is often used in conjunction with other fluorescent proteins for multicolor imaging or in high-throughput screening processes.

In summary, mtKeima is a specialized, pH-sensitive fluorescent protein primarily utilized in cellular and molecular biology to investigate mitochondrial function and intracellular environments. Its unique excitation properties facilitate detailed, real-time imaging of dynamic biological processes within living cells.