ZNF318 is a 2279 amino acid endocrine regulatory protein that localizes to the nucleus. Highly expressed in testis, ovaries and kidneys, ZNF318 is a co-repressor of androgen receptor (AR)-mediated transcriptional activation and is thought to regulate transcription during spermatogenesis. ZNF318 interacts with the N-terminal domain of AR and contains two matrin-type zinc fingers. Two isoforms of ZNF318, designated TZF and TZF-L, are produced due to alternative splicing events. Each of these splice variants are thought to have unique roles in transcriptional regulation. While the TZF isoform functions as a repressor of AR-mediated transcriptional activation, the TZF-L isoform is thought to enhance AR-mediated transcriptional activation.