The Protein Knowledge Network (ProKN), developed by the University of Delaware as part of the NIH Common Fund Data Ecosystem (CFDE), is an integrative bioinformatics platform designed to harmonize and explore complex relationships within protein-related data. By utilizing a knowledge graph approach, ProKN links proteins with their post-translational modifications, genetic variants, and functional pathways, offering specialized tools like KSMoFinder for predicting kinase-substrate interactions, as well as services for ID mapping, variant mapping, and protein embeddings. ProKN supports the FAIR data enabling researchers to bridge disparate datasets and generate new hypotheses for precision medicine and drug discovery.