<p>Intrinsically disordered regions (IDRs) drive intracellular phase separation and biomolecular condensate formation through interactions encoded in their sequence. Although condensates form spatially distinct assemblies in cells, the high conformational flexibility of IDRs and absence of well-defined 3D structures raise the question of how they could encode condensate specificity. To systematically characterize IDR–IDR interactions and their ability to mediate self-specific partitioning, we develop <i>micDROP</i>, a synthetic system of multivalent IDRs forming constitutive droplets. We examine ten natural IDRs that phase-separate in <i>micDROP</i> and find that their saturation concentrations in vivo correlate with total sequence stickiness. Co-expression of IDR pairs fused to distinct <i>micDROP</i> scaffolds reveals widespread promiscuity, whereas TDP43 and UBQ2 consistently form self-specific condensates. A short, conserved α-helical segment in the TDP43 IDR governs this self-recognition. Our results indicate that IDRs tune phase separation propensity through sequence composition, while discrete condensate identity likely requires additional structural determinants.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Mapping interactions between disordered regions reveals promiscuity in biomolecular condensate formation

  • Atar Gilat,
  • Alexander I. Alexandrov,
  • Benjamin Dubreuil,
  • Emmanuel D. Levy

摘要

Intrinsically disordered regions (IDRs) drive intracellular phase separation and biomolecular condensate formation through interactions encoded in their sequence. Although condensates form spatially distinct assemblies in cells, the high conformational flexibility of IDRs and absence of well-defined 3D structures raise the question of how they could encode condensate specificity. To systematically characterize IDR–IDR interactions and their ability to mediate self-specific partitioning, we develop micDROP, a synthetic system of multivalent IDRs forming constitutive droplets. We examine ten natural IDRs that phase-separate in micDROP and find that their saturation concentrations in vivo correlate with total sequence stickiness. Co-expression of IDR pairs fused to distinct micDROP scaffolds reveals widespread promiscuity, whereas TDP43 and UBQ2 consistently form self-specific condensates. A short, conserved α-helical segment in the TDP43 IDR governs this self-recognition. Our results indicate that IDRs tune phase separation propensity through sequence composition, while discrete condensate identity likely requires additional structural determinants.