Studies on peptide:N-glycanase-p97 interaction suggest that p97 phosphorylation modulates endoplasmic reticulum-associated degradation.
During endoplasmic reticulum-associated degradation, the multifunctional AAA ATPase p97 is part of a protein degradation complex. p97 associates via its N-terminal domain with various cofactors to recruit ubiquitinated substrates. It also interacts with alternative substrate-processing cofactors, such as Ufd2, Ufd3, and peptide:N-glycanase (PNGase) in higher eukaryotes. These cofactors determine different fates of the substrates and they all bind outside of the N-terminal domain of p97. Here, we describe a cofactor-binding motif of p97 contained within the last 10 amino acid residues of the C terminus, which is both necessary and sufficient to mediate interactions of p97 with PNGase and Ufd3. The crystal structure of the N-terminal domain of PNGase in complex with this motif provides detailed insight into the interaction between p97 and its substrate-processing cofactors. Phosphorylation of p97's highly conserved penultimate tyrosine residue, which is the main phosphorylation site during T cell receptor stimulation, completely blocks binding of either PNGase or Ufd3 to p97. This observation suggests that phosphorylation of this residue modulates endoplasmic reticulum-associated protein degradation activity by discharging substrate-processing cofactors.
Zhao
Gang
G
Center for Structural Biology, Deparatment of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5115, USA.
Zhou
Xiaoke
X
Wang
Liqun
L
Li
Guangtao
G
Schindelin
Hermann
H
Lennarz
William J
WJ
D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D000818:Animals; D018360:Crystallography, X-Ray; D004247:DNA / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000201:enzymology*; D051379:Mice; D008958:Models, Molecular; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine / Q000378:metabolism; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary
D009687:Nuclear Proteins; D019000:Phosphotyrosine; D004247:DNA; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D000251:Adenosine Triphosphatases; C404942:p97 ATPase