Illuminating Dark Chemical Matter Using the Cell Painting Assay.

Area of Science:

• Drug discovery and development
• Chemical biology
• Cellular imaging

Background:

• Drug discovery relies on screening compound libraries for bioactive molecules.
• A significant portion of synthesized compounds, termed "dark chemical matter" (DCM), remains uncharacterized due to inactivity in traditional assays.
• Deorphanizing DCM is a promising strategy for identifying highly selective drug candidates with minimal off-target effects.

Purpose of the Study:

• To investigate the utility of morphological profiling via the Cell Painting assay for detecting bioactive compounds within DCM.
• To identify novel modulators of cellular processes from the DCM collection.
• To demonstrate the potential of phenotypic screening for deorphanizing uncharacterized compound libraries.

Main Methods:

• Utilized Cell Painting, a high-content imaging assay, to generate morphological profiles of cells treated with DCM compounds.
• Screened a diverse DCM collection to identify compounds exhibiting significant phenotypic changes.
• Validated identified hits through confirmation of their modulatory effects on specific biological pathways.

Main Results:

• Successfully identified bioactive compounds within the DCM collection using morphological profiling.
• Confirmed several DCM compounds as modulators of critical cellular processes, including microtubule dynamics, DNA synthesis, and pyrimidine biosynthesis.
• Demonstrated the power of unbiased phenotypic screening in uncovering novel bioactivity within large, uncharacterized compound sets.

Conclusions:

• Morphological profiling with Cell Painting is an effective and unbiased method for probing compound libraries and deorphanizing DCM.
• This approach facilitates the discovery of novel, selective small-molecule modulators with therapeutic potential.
• Phenotypic screening offers a valuable strategy for unlocking the hidden potential of "dark chemical matter" in drug discovery.