Beyond DNA: new probes for PAINT super-resolution microscopy

Area of Science:

• Biophysics
• Nanotechnology
• Microscopy

Background:

• Point Accumulation for Imaging in Nanoscale Topography (PAINT) is a powerful single-molecule localization microscopy (SMLM) technique.
• Current DNA-PAINT methods rely on transient DNA interactions for molecular imaging.
• A growing need exists for PAINT probes independent of DNA for broader SMLM applications.

Purpose of the Study:

• To review non-DNA-based PAINT probes for SMLM.
• To discuss the applications and challenges of these novel probes.
• To highlight advancements in the PAINT toolbox.

Main Methods:

• Literature review of scientific publications on PAINT probes.
• Categorization of non-DNA PAINT probes based on their binding mechanisms.
• Analysis of reported applications and limitations.

Main Results:

• Identified four main categories of DNA-free PAINT probes: endogenous interactions, engineered binders, fusion proteins, and synthetic molecules.
• Demonstrated diverse applications of these probes in SMLM.
• Outlined current challenges and future directions for non-DNA PAINT probe development.

Conclusions:

• Non-DNA PAINT probes significantly expand the versatility and applicability of SMLM.
• These alternative probes offer complementary strategies for nanoscale imaging.
• Further research into novel binding mechanisms will enhance SMLM capabilities.