Аннотация:Ultrasonic cleavage of polymers has been a subject of intensive studies during the past decades. Currently used experimental protocols and techniques for manipulation with nucleic acids allow us to conduct ultrasonic cleavage experiments with DNA fragments of known length and base pair sequence. Analysis of ultrasonic cleavage products with polyacrylamide gel electrophoresis, in turn, makes it possible to determine the exact positions of DNA cleavage sites and corresponding cleavage efficiencies. In our study the phenomenon of ultrasonic cleavage of DNA has been analyzed in details. Two main effects are observed in DNA cleavage patterns: attenuation of ultrasonic cleavage at sites that are closer to the ends of the DNA fragments and sequence-specificity of cleavage. Here we propose the approach and develop the model which can describe these two effects. The approach is based on the analysis of ultrasound - induced DNA cleavage using high resolution denaturing polyacrylamide gel electrophoresis. Our model describes the extension of the DNA molecules in cavitational flows that leads to the mechanochemical cleavage of DNA. The sequence specificity of ultrasonic cleavage is shown to be likely the result of sequence-dependent conformational dynamics. Hence, the relative efficiency of ultrasonic cleavage may serve as indicator of sequence specific flexibility in both strands of DNA. Such numerical evaluation may be useful for identifying promoter regions in the genome and assessing preferences for nucleosome positioning.