Chemical Engineering of Transcription Factors Uncovered Cell-Permeable μMax Modulators.

Area of Science:

• Protein engineering
• Chemical biology
• Synthetic biology

Background:

• Transcription factor engineering is vital for research and biomedicine.
• Current analogs are limited by native sequences and structures.
• Advanced analogs with noncanonical modifications are needed.

Purpose of the Study:

• To engineer novel abiotic transcription factors with enhanced stability and cell permeability.
• To create advanced analogs with noncanonical modifications for improved functional properties.

Main Methods:

• Rational design and total chemical synthesis of transcription factor analogs.
• Solid-phase synthesis and native chemical ligation to create a library of 30 Max-derived analogs.
• DNA-binding analysis and cellular uptake studies to identify lead compounds.

Main Results:

• Identified the μMax20 analog with mutations (Lys31, Lys57 to hArg) showing potent DNA binding and cell permeability.
• Site-specific modifications with aromatic staples improved stability and cellular delivery at nanomolar concentrations.
• The lead μMax20 analog suppressed Myc-driven gene expression and exhibited antiproliferative activity against Myc-dependent cancer cells.

Conclusions:

• Combining chemical protein synthesis with late-stage modifications enhances protein function.
• Novel abiotic transcription factors can be engineered for enhanced stability, cell permeability, and biological activity.
• Engineered transcription factors show potential as bioactive modulators for therapeutic applications.