title: Gln40 deamidation blocks structural reconfiguration and activation of SCF ubiquitin ligase complex by Nedd8.
abstract: The full enzymatic activity of the cullin-RING ubiquitin ligases (CRLs) requires a ubiquitin-like protein (that is, Nedd8) modification. By deamidating Gln40 of Nedd8 to glutamate (Q40E), the bacterial cycle-inhibiting factor (Cif) family is able to inhibit CRL E3 activities, thereby interfering with cellular functions. Despite extensive structural studies on CRLs, the molecular mechanism by which Nedd8 Gln40 deamidation affects CRL functions remains unclear. We apply a new quantitative cross-linking mass spectrometry approach to characterize three different types of full-length human Cul1-Rbx1 complexes and uncover major Nedd8-induced structural rearrangements of the CRL1 catalytic core. More importantly, we find that those changes are not induced by Nedd8(Q40E) conjugation, indicating that the subtle change of a single Nedd8 amino acid is sufficient to revert the structure of the CRL catalytic core back to its unmodified form. Our results provide new insights into how neddylation regulates the conformation and activity of CRLs.
authors.affiliation: Department of Physiology and Biophysics, University of California, Irvine, California 92697, USA.
authors.forename: Clinton
authors.initials: C
authors.lastname: Yu
authors.affiliation: Department of Pharmacology and Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Haibin
authors.initials: H
authors.lastname: Mao
authors.affiliation: Department of Chemistry, University of California, Irvine, California 92697, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Novitsky
authors.affiliation: Department of Pharmacology and Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Tang
authors.affiliation: Department of Chemistry, University of California, Irvine, California 92697, USA.
authors.forename: Scott D
authors.initials: SD
authors.lastname: Rychnovsky
authors.affiliation: Department of Pharmacology and Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Ning
authors.initials: N
authors.lastname: Zheng
authors.affiliation: Department of Physiology and Biophysics, University of California, Irvine, California 92697, USA.
authors.forename: Lan
authors.initials: L
authors.lastname: Huang
mesh_terms: D020816:Amino Acid Motifs; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain; D044842:Cullin Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003641:Deamination; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism*; D006801:Humans; D013058:Mass Spectrometry; D000075687:NEDD8 Protein; D011485:Protein Binding; D044843:SKP Cullin F-Box Protein Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014452:Ubiquitins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; C100318:Cullin 1; D044842:Cullin Proteins; D000075687:NEDD8 Protein; C082860:NEDD8 protein, human; C479529:RBX1 protein, human; D014452:Ubiquitins; D005973:Glutamine; D018698:Glutamic Acid; C584471:CULL-RING ligase, human; D044843:SKP Cullin F-Box Protein Ligases; D044767:Ubiquitin-Protein Ligases