7RL3

Structure of Drosophila melanogaster Plk4 PB3

7RL3 の概要

• エントリーDOI: 10.2210/pdb7rl3/pdb
• 分子名称: Serine/threonine-protein kinase PLK4 (2 entities in total)
• 機能のキーワード: kinase, sak kinase, plk4, polo box, signaling protein, transferase
• 由来する生物種: Drosophila melanogaster (Fruit fly)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 19864.63

構造登録者

Slep, K.C.,Slevin, L.K. (登録日: 2021-07-23, 公開日: 2022-08-03, 最終更新日: 2023-08-16)

主引用文献

Ryniawec, J.M.,Buster, D.W.,Slevin, L.K.,Boese, C.J.,Amoiroglou, A.,Dean, S.M.,Slep, K.C.,Rogers, G.C.
Polo-like kinase 4 homodimerization and condensate formation regulate its own protein levels but are not required for centriole assembly.
Mol.Biol.Cell, 34:ar80-ar80, 2023

PubMed Abstract: Polo-like kinase 4 (Plk4) is the master-regulator of centriole assembly, and cell cycle-dependent regulation of its activity maintains proper centrosome number. During most of the cell cycle, Plk4 levels are nearly undetectable due to its ability to autophosphorylate and trigger its own ubiquitin-mediated degradation. However, during mitotic exit, Plk4 forms a single aggregate on the centriole surface to stimulate centriole duplication. Whereas most Polo-like kinase family members are monomeric, Plk4 is unique because it forms homodimers. Notably, Plk4 -autophosphorylates a degron near its kinase domain, a critical step in autodestruction. While it is thought that the purpose of homodimerization is to promote -autophosphorylation, this has not been tested. Here, we generated separation-of-function Plk4 mutants that fail to dimerize and show that homodimerization creates a binding site for the Plk4 activator, Asterless. Surprisingly, however, Plk4 dimer mutants are catalytically active in cells, promote centriole assembly, and can -autophosphorylate through concentration-dependent condensate formation. Moreover, we mapped and then deleted the weak-interacting regions within Plk4 that mediate condensation and conclude that dimerization and condensation are not required for centriole assembly. Our findings suggest that Plk4 dimerization and condensation function simply to down-regulate Plk4 and suppress centriole overduplication.

PubMed: 37163316
DOI: 10.1091/mbc.E22-12-0572

実験手法

X-RAY DIFFRACTION (1.75 Å)