Extended Data Fig. 4: Heat shock limits asincRNAs and triggers sincRNA-dependent nucleolar phase transitions.
From: Nucleolar RNA polymerase II drives ribosome biogenesis
a, Heat shock (43 °C) rapidly induces the formation of intranucleolar liquid droplets harbouring the ACM-containing VHL protein. b, Gradual amyloid-body (A-body) formation. The stress-induced, mobile and spherical liquid-like foci (yellow arrowhead) gradually transition into irregularly shaped, solid-like amyloid bodies (cyan arrowhead) in cells subjected to heat shock (43 °C)19. c, The appearance of early-stage, ACM-marked, liquid-like foci18,19 in cells subjected to a 15-min heat-shock treatment is abrogated upon siRNA-mediated knockdown of either sincRNA16 or sincRNA22. d, In a cell-free in vitro system, the low-complexity sincRNA (1 μM) forms liquid droplets when mixed with the ACM of human VHL or β-amyloid proteins (25 μM). Droplets were detected using fluorescently labelled RNA (5′FAM) and differential interference contrast (DIC). e, ss-RNA-seq reveals that sincRNA levels increase while asincRNA levels decrease across the IGS following a 30-min heat shock. Heat shock increases sincRNA levels by 607% and decreases asincRNA levels by 38%. a–e, Nucleolar-stress hyperresponsive MCF7 cells were used where applicable; images are representative of two independent experiments; scale bars, 5 μm.
