Correlative microscopy: bridging the gap between fluorescence light microscopy and cryo-electron tomography

Area of Science:

• Cell Biology
• Microscopy Techniques
• Structural Biology

Background:

• Cryo-electron tomography (cryo-ET) provides high-resolution 3D views of cellular structures.
• Low contrast and radiation sensitivity in cryo-ET lead to poor signal-to-noise ratios.
• Identifying regions of interest for cryo-ET is challenging and time-consuming.

Purpose of the Study:

• To develop an efficient method for locating specific cellular structures for cryo-ET.
• To minimize radiation dose during the search for target regions.
• To integrate fluorescence light microscopy with cryo-electron microscopy.

Main Methods:

• A correlative cryo-light microscopy and cryo-electron microscopy workflow was established.
• Fluorescently labeled cells were vitrified and imaged using a specialized cryo-holder.
• Absolute coordinates were transferred from light microscopy to electron microscopy via a user interface.

Main Results:

• The correlative approach significantly reduces the dose required for locating regions of interest.
• The method successfully identified and enabled high-resolution imaging of cellular structures.
• The workflow was validated using neuronal and keratinocyte cell lines.

Conclusions:

• Correlative cryo-light and electron microscopy is an effective strategy for targeted cryo-ET.
• This technique enhances the efficiency of studying complex cellular architectures.
• The developed method facilitates nanometer-scale resolution imaging of specific biological targets.