The article explores the role of DNA shape in protein-DNA recognition, focusing on the binding of arginines to narrow minor grooves. The authors analyze the three-dimensional structures of protein-DNA complexes to demonstrate that arginines are significantly enriched in narrow minor grooves, which are often associated with A-tracts (AT-rich sequences). This binding mechanism leverages the enhanced negative electrostatic potential of narrow minor grooves, facilitating protein-DNA interactions. The study highlights that the ability to detect local variations in DNA shape and electrostatic potential is a general mechanism for protein-DNA recognition, providing insights into the structural and energetic origins of binding specificity. The findings have implications for predicting transcription factor binding sites in genomes and understanding the complex interactions between proteins and DNA.The article explores the role of DNA shape in protein-DNA recognition, focusing on the binding of arginines to narrow minor grooves. The authors analyze the three-dimensional structures of protein-DNA complexes to demonstrate that arginines are significantly enriched in narrow minor grooves, which are often associated with A-tracts (AT-rich sequences). This binding mechanism leverages the enhanced negative electrostatic potential of narrow minor grooves, facilitating protein-DNA interactions. The study highlights that the ability to detect local variations in DNA shape and electrostatic potential is a general mechanism for protein-DNA recognition, providing insights into the structural and energetic origins of binding specificity. The findings have implications for predicting transcription factor binding sites in genomes and understanding the complex interactions between proteins and DNA.