Fluorescence protein complementation in microscopy: applications beyond detecting bi-molecular interactions.

Area of Science:

• Biochemistry
• Molecular Biology
• Microscopy

Background:

• Traditional bimolecular fluorescence complementation (BiFC) relies on protein proximity to form fluorescent species.
• Conventional BiFC uses protein fragments that only emit light when interacting proteins bring them together.

Purpose of the Study:

• To highlight the utility of spontaneously complementing fluorescent protein fragments.
• To encourage further development and application of these self-associating fragments.

Main Methods:

• Review of literature on fluorescent protein fragment complementation.
• Focus on superfolder green fluorescent protein (GFP) derived fragments (GFP1-10 and GFP11).

Main Results:

• Certain fluorescent protein fragments, specifically GFP1-10 and GFP11, exhibit spontaneous complementation.
• These fragments serve as effective folding reporters for high-throughput expression and structural biology.
• Self-associating fragments are valuable for live imaging, including labeling specific synapses and visualizing protein topology.

Conclusions:

• Spontaneously complementing fluorescent protein fragments offer unique advantages for live imaging and protein studies.
• The GFP11 tag is particularly useful when full-length fluorescent proteins hinder protein function or imaging.
• These tools have broad potential in live imaging of pathogens and understanding subcellular protein localization.