Is a negative regulator of proteasomal degradation of a set of methylated proteins, including DNMT1 and SOX2 (PubMed:24492612, PubMed:29358331). Involved in the maintainance of embryonic stem cells pluripotency, through the regulation of SOX2 levels (By similarity). {ECO:0000250|UniProtKB:Q8CCJ9, ECO:0000269|PubMed:24492612, ECO:0000269|PubMed:29358331}. This is the function of ENSG00000129292 (PHF20L1, PHD finger protein 20 like 1).