Liu et al. demonstrate that the intrinsically disordered regions (IDRs) of phase-separation proteins (e.g., the IDR domain of FUS protein) can promote transcription activation by dCas9-VPR through multivalent interaction. As indicated, the matchstick represents dCa9-VPR transcription activator, and the rope represents FUS IDR. The little matchstick girl draws one matchstick to warm herself. But the snowy night is really cold, only a bundle of matchsticks tied together with FUS IDR (named dCas9-VPRF) could keep her warm for a little while, highlighting the role of FUS IDR in transcription activation.