{"doi":"10.1021/jacs.2c04477","title":"Development of a GalNAc-Tyrosine-Specific Monoclonal Antibody and Detection of Tyrosine <i>O</i>-GalNAcylation in Numerous Human Tissues and Cell Lines","abstract":"Glycosylation is a vital post-translational modification involved in a range of biological processes including protein folding, signaling, and cell–cell interactions. In 2011, a new type of O-linked glycosylation was discovered, wherein the side-chain oxygen of tyrosine is modified with a GalNAc residue (GalNAc-Tyr). At present, very little is known about GalNAc-Tyr prevalence, function, or biosynthesis. Herein, we describe the design and synthesis of a GalNAc-Tyr-derived hapten and its use in generating a GalNAc-Tyr selective monoclonal antibody. The antibody, G10C, has an unusually high affinity (app KD = 100 pM) and excellent selectivity for GalNAc-Tyr. We also obtained a crystal structure of the G10C Fab region in complex with 4-nitrophenyl-N-acetyl-α-d-galactosaminide (a small molecule mimic of GalNAc-Tyr) providing insights into the structural basis for high affinity and selectivity. Using this antibody, we discovered that GalNAc-Tyr is widely expressed in most human tissues, indicating that it is a ubiquitous and underappreciated post-translational modification. Localization to specific cell types and organ substructures within those tissues indicates that GalNAc-Tyr is likely regulated in a cell-specific manner. GalNAc-Tyr was also observed in a variety of cell lines and primary cells but was only present on the external cell surface in certain cancer cell lines, suggesting that GalNAc-Tyr localization may be altered in cancer cells. Collectively, the results shed new light on this under-studied form of glycosylation and provide access to new tools that will enable expanded biochemical and clinical investigations.","journal":"Journal of the American Chemical Society","year":2022,"id":270352,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":14,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.954,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":558821,"name":"Tiffany R. Bellomo","orcid":"0000-0001-6884-3117","position":1,"is_corresponding":false},{"id":726244,"name":"Ruslan Gibadullin","orcid":"0000-0001-8439-0218","position":2,"is_corresponding":false},{"id":519328,"name":"Molly D. Congdon","orcid":"0000-0002-9096-1344","position":3,"is_corresponding":false},{"id":279369,"name":"Elijah F. Edmondson","orcid":"0000-0002-6106-3705","position":4,"is_corresponding":false},{"id":623765,"name":"Mi Li","orcid":"0000-0002-9304-4146","position":5,"is_corresponding":false},{"id":376430,"name":"Alexander Wlodawer","orcid":"0000-0002-5510-9703","position":6,"is_corresponding":false},{"id":934600,"name":"Crystal Li","orcid":null,"position":7,"is_corresponding":false},{"id":915580,"name":"J. Sebastian Temme","orcid":"0000-0001-8306-2810","position":8,"is_corresponding":false},{"id":934156,"name":"Pavan Patel","orcid":"0000-0001-7175-4692","position":9,"is_corresponding":false},{"id":497095,"name":"Donna Butcher","orcid":"0000-0002-2065-8067","position":10,"is_corresponding":false},{"id":519329,"name":"Jeffrey C. Gildersleeve","orcid":"0000-0002-3744-6423","position":11,"is_corresponding":false},{"id":113528,"name":"Li Xia","orcid":null,"position":0,"is_corresponding":true}],"reference_count":43,"raw_metadata":null,"created_at":"2026-07-19T00:27:26.772098Z","pmid":"36054098","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}