What is the difference between GFP and YFP?

Difference Between GFP and YFP

Green Fluorescent Protein (GFP) and Yellow Fluorescent Protein (YFP) are both members of the fluorescent protein family, widely used as markers in molecular and cellular biology. Despite their similarities, they have distinct characteristics and applications.

Key Differences

• Wavelength: GFP emits green light with a peak at approximately 509 nm, while YFP emits yellow light, with a peak emission at around 527 nm.
• Origin: Both proteins originally derive from the jellyfish Aequorea victoria, but YFP is a mutated version of GFP, engineered to shift the emission spectrum.
• Applications: GFP is used for general labeling of cells and cellular components, whereas YFP, due to its longer wavelength, is often used in energy transfer experiments such as FRET (Förster Resonance Energy Transfer) to study protein-protein interactions.
• Sensitivity: YFP is more sensitive to pH changes and chloride ions than GFP, which can affect its fluorescence intensity and stability.
• Mutation: The shift from GFP to YFP involves specific mutations, typically at positions 64, 65, and 72 (e.g., S65G, V68L, S72A), leading to the spectral shift.

In summary, while GFP and YFP share a common origin and structural similarities, they are distinguished by their emission wavelengths, sensitivity to environmental factors, and specific applications in biological research. Choosing between GFP and YFP depends on the specific requirements of the experiment, including desired wavelength, sensitivity to pH and ions, and the need for FRET applications.