The function of PELI1 (pellino E3 ubiquitin protein ligase 1, Ensembl gene identifier ENSG00000197329) is as follows. E3 ubiquitin ligase catalyzing the covalent attachment of ubiquitin moieties onto substrate proteins (PubMed:12496252, PubMed:17675297, PubMed:29883609, PubMed:30952868). Involved in the TLR and IL-1 signaling pathways via interaction with the complex containing IRAK kinases and TRAF6 (PubMed:12496252, PubMed:17675297). Acts as a positive regulator of inflammatory response in microglia through activation of NF-kappa-B and MAP kinase (By similarity). Mediates 'Lys- 63'-linked polyubiquitination of IRAK1 allowing subsequent NF-kappa-B activation (PubMed:12496252, PubMed:17675297). Conjugates 'Lys-63'- linked ubiquitin chains to the adapter protein ASC/PYCARD, which in turn is crucial for NLRP3 inflammasome activation (PubMed:34706239). Mediates 'Lys-48'-linked polyubiquitination of RIPK3 leading to its subsequent proteasome-dependent degradation; preferentially recognizes and mediates the degradation of the 'Thr-182' phosphorylated form of RIPK3 (PubMed:29883609). Negatively regulates necroptosis by reducing RIPK3 expression (PubMed:29883609). Mediates 'Lys-63'-linked ubiquitination of RIPK1 (PubMed:29883609). Following phosphorylation by ATM, catalyzes 'Lys-63'-linked ubiquitination of NBN, promoting DNA repair via homologous recombination (PubMed:30952868). Negatively regulates activation of the metabolic mTORC1 signaling pathway by mediating 'Lys-63'-linked ubiquitination of mTORC1-inhibitory protein TSC1 and thereby promoting TSC1/TSC2 complex stability (PubMed:33215753). {ECO:0000250|UniProtKB:Q8C669, ECO:0000269|PubMed:12496252, ECO:0000269|PubMed:17675297, ECO:0000269|PubMed:29883609, ECO:0000269|PubMed:30952868, ECO:0000269|PubMed:33215753}.