PT  - JOURNAL ARTICLE
AU  - Kartikeya Vijayasimha
AU  - Amy L. Leestemaker-Palmer
AU  - James S. Gibbs
AU  - Jonathan W. Yewdell
AU  - Brian P. Dolan
TI  - NEDD8 activity is important for direct antigen MHC class I antigen presentation
AID  - 10.1101/2022.02.25.482016
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.02.25.482016
4099  - http://biorxiv.org/content/early/2022/02/27/2022.02.25.482016.short
4100  - http://biorxiv.org/content/early/2022/02/27/2022.02.25.482016.full
AB  - Successful direct MHC class I antigen presentation is dependent on the protein degradation machinery of the cell to generate antigenic peptides which can be loaded onto MHC class I molecules for surveillance by CD8+ T cells of the immune system. Most often this process involves the ubiquitin-proteasome system, however other ubiquitin-like (UBL) proteins have also been implicated in protein degradation and direct antigen presentation. Here, we examine the role of neuronal precursor cell-expressed developmentally down-regulated protein 8 (NEDD8) in direct antigen presentation. NEDD8 is the UBL with highest similarity to ubiquitin and fusion of NEDD8 to the amino-terminus of a target protein can lead to the target proteins degradation. We find that appending NEDD8 to the N-terminus of the model antigen ovalbumin resulted in degradation by both the proteasome and autophagy protein degradation pathways, but only proteasomal degradation, involving the proteasomal subunit NEDD8 ultimate buster 1 (NUB1), resulted in peptide presentation. When directly compare to ubiquitin, NEDD8-fusion was less efficient at generating peptides. However, inactivation of the NEDD8-conugation machinery by treating cells with MLN4924, inhibited the presentation of peptides from Defective Ribosomal Products (DRiPs) derived from a model antigen. These results demonstrate that NEDD8 activity in the cell is important for direct antigen presentation, but not by directly targeting proteins for degradation.Competing Interest StatementThe authors have declared no competing interest.3MA3-methyladenineDRiPDefective ribosomal productNCnon-cleavableNEDD8neuronal precursor cell-expressed developmentally down-regulated protein 8NUB1NEDD8 ultimate buster 1 rVV –recombinant vaccinia virusSCRAPShield-controlled recombinant antigenic proteinTUBETandem Ubiquitin Binding EntitiesUBLUbiquitin-like proteinUbUbiquitin