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Ubiquitylation‐dependent oligomerization regulates activity of Nedd4 ligases
Author(s) -
Attali Ilan,
Tobelaim William Sam,
Persaud Avinash,
Motamedchaboki Khatereh,
SimpsonLavy Kobi J,
Mashahreh Bayan,
LevinKravets Olga,
KerenKaplan Tal,
Pilzer Inbar,
Kupiec Martin,
Wiener Reuven,
Wolf Dieter A,
Rotin Daniela,
Prag Gali
Publication year - 2017
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.15252/embj.201694314
Subject(s) - ubiquitin ligase , ubiquitin , biology , allosteric regulation , ubiquitin protein ligases , nedd4 , microbiology and biotechnology , biochemistry , lysine , dna ligase , receptor , amino acid , dna , gene
Ubiquitylation controls protein function and degradation. Therefore, ubiquitin ligases need to be tightly controlled. We discovered an evolutionarily conserved allosteric restraint mechanism for Nedd4 ligases and demonstrated its function with diverse substrates: the yeast soluble proteins Rpn10 and Rvs167, and the human receptor tyrosine kinase FGFR 1 and cardiac I KS potassium channel. We found that a potential trimerization interface is structurally blocked by the HECT domain α1‐helix, which further undergoes ubiquitylation on a conserved lysine residue. Genetic, bioinformatics, biochemical and biophysical data show that attraction between this α1‐conjugated ubiquitin and the HECT ubiquitin‐binding patch pulls the α1‐helix out of the interface, thereby promoting trimerization. Strikingly, trimerization renders the ligase inactive. Arginine substitution of the ubiquitylated lysine impairs this inactivation mechanism and results in unrestrained FGFR 1 ubiquitylation in cells. Similarly, electrophysiological data and TIRF microscopy show that NEDD 4 unrestrained mutant constitutively downregulates the I KS channel, thus confirming the functional importance of E3‐ligase autoinhibition.