psself204-phasepdb

Basic information

PhaSepDB ID	psself204	Reference	32385244	Uniprot Entry	Q9Z340	Gene names	Par3
Class	PS-self	Location	Cytoplasm	MLO	Par complex

LLPS related evidences

Publication note	Here we show that the Par complex exhibits cell cycle-dependent condensation in Drosophila neuroblasts, driven by liquid-liquid phase separation. The open conformation of Par3 undergoes autonomous phase separation likely due to its NTD-mediated oligomerization. Par6, via C-terminal tail binding to Par3 PDZ3, can be enriched to Par3 condensates and in return dramatically promote Par3 phase separation. aPKC can also be concentrated to the Par3N/Par6 condensates as a client. Interestingly, activated aPKC can disperse the Par3/Par6 condensates via phosphorylation of Par3. Perturbations of Par3/Par6 phase separation impair the establishment of apical-basal polarity during neuroblast asymmetric divisions and lead to defective lineage development. (Organism: Rattus norvegicus; Cell line: COS-7 cells)
Material state	liquid,hydrogel : FRAP analysis revealed that both Par3N and Par6β in the condensed puncta rapidly exchanged with the proteins in the surrounding cytoplasm. Those Par3N/Par6β droplets transitioned into gel-like structures over time, and the droplets rarely fused together after 20 min.
LLPS region	1-1337,1-685,1–854	Key domains	N-terminal domain (NTD),PDZ3 : Removing NTD (ΔNTD) from Par3N significantly reduced phase separation efficiency of the Par3N/Par6β complex, as well as that of Par3N alone. deletion of PDZ3 (ΔPDZ3) but not PDZ1 (ΔPDZ1) from Par3N effectively impaired LLPS of the Par3N/Par6β complex.
LLPS diagram (Click the image to enlarge)	_

LLPS partner

Protein partner	Par6,aPKC ( Q9JK83,Q62074 )	Par6, via C-terminal tail binding to Par3 PDZ3, can be enriched to Par3 condensates and in return dramatically promote Par3 phase separation. aPKC can also be concentrated to the Par3N/Par6 condensates as a client.
RNA partner	_	_
Others	_	_

LLPS regulation

PTM	phosphorylation	Activated aPKC can disperse the Par3/Par6 condensates via phosphorylation of Par3.
Mutation	p.V13D,p.D70K,p.S827E,p.S829E	When introducing a V13D, D70K mutation in Par3 NTD (referred to as NTDmu), which disrupts its oligomerization, only very few puncta could be detected. Fewer puncta were observed when Par6β was co-expressed with Par3 Δ4N12 S827,829E when compared with Par3 Δ4N12.
Alternative splicing	_
Repeat	_
Oligomerization	Removing NTD (ΔNTD) from Par3N significantly reduced phase separation efficiency of the Par3N/Par6β complex, as well as that of Par3N alone.