The RelA-associated inhibitor, PPP1R13L, AMFR, RNF45.  It is an inhibitor of the ASPP protein, iASPP, also called the NFkB-interacting protein 1 (Bergamaschi et al. 2003).  See also the family description and Zheng et al. 2022. It is an E3 ubiquitin-protein ligase, AMFR, of 643 aas and 6 - 8 TMSs in the first (N-terminal) half of the protein.  The second (C-terminal) half is hydrophilic. This E3 ubiquitin-protein ligase mediates the polyubiquitination of lysine and cysteine residues in target proteins, such as CD3D, CYP3A4, CFTR, INSIG1, SOAT2/ACAT2 and APOB for proteasomal degradation (Shimizu et al. 1999, Liu et al. 2014, Wang et al. 2017). Homologs of AMFR can be found in the ER-RT family (TC# 3.A.16), the PPI family (TC# 3.A.20) and the Rcf family (8.A.112).