psself346-phasepdb

Basic information

PhaSepDB ID	psself346	Reference	33731873	Uniprot Entry	Q9H9J4-2	Gene names	USP42
Class	PS-self	Location	Nucleus	MLO	Nuclear speckle

LLPS related evidences

Publication note	In this study, we present evidence that human USP42 forms liquid droplets in the nucleus through LLPS. We confirm that the positively charged motifs in its C-terminal disordered region drive phase separation and nuclear speckle incorporation, with its DUB activity playing an essential role. Depletion of USP42 leads to a reduced number of nuclear speckles and attenuated cell growth. (Organism: Homo sapiens; Cell line: HeLa cells,U2OS cells,COS-7 cells,HEK293T cells)
Material state	liquid : GFP-USP42 punctae demonstrated fluid features through fusion phenomena
LLPS region	742-1316	Key domains	C-terminal disordered region : the disordered region that is C-terminal to the USP domain appeared to dominate the subcellular localization of USP42, as two constructs lacking this region (USP42-∆C and USP42-USP domain) exhibited diffuse distribution throughout the cell, while this region alone displayed nuclear puncta localization.
LLPS diagram (Click the image to enlarge)	Summarized diagram showing the in vitro phase separation of purified GFP-USP42 fusion proteins in the absence (left) or presence (right) of the crowding agent PEG 4000 (25%).

LLPS partner

Protein partner	SC35,PLRG1 ( Q01130,O43660 )	no condensation was detected in vitro with purified PLRG1 proteins, thus indicating limited capability to phase separate on its own. However, when the USP42 C-terminal fragment (non-GFP-tagged) was added, GFP-tagged PLRG1 was readily incorporated into liquid droplets as revealed by RC and fluorescence microscopy. we carried out confocal microscopy assays using the well-established marker SC35 and observed evident colocalization of GFP-USP42 with SC35-positive nuclear speckles.
RNA partner	_	_
Others	_	_

LLPS regulation

PTM	_	_
Mutation	∆C,p.C120A	USP42-∆C exhibited diffuse distribution throughout the cell. although the USP42-C120A condensates failed to integrate into neighbouring nuclear speckles, these structures nevertheless exhibited fluid features and showed FRAP recovery, although to a lesser extent compared to wild type but resembled how the C-terminus truncation performed.
Alternative splicing	_
Repeat	_
Oligomerization	_