RNA-binding protein that plays an essential role in spermatogenesis. May act by binding to the 3'-UTR of mRNAs and regulating their translation. Forms a heterodimer with BOLL and DAZL. Interacts with PUM2, DAZAP1, DAZAP2, DZIP1 and DZIP3. Predominantly cytoplasmic. Nuclear at some stages of spermatozoide development. Localizes both to the nuclei and cytoplasm of spermatozoide differentiation. Nuclear in fetal gonocytes and in spermatogonial nuclei. It then relocates to the cytoplasm during male meiosis. Testis specific. The DAZ domains are essential and mediate the interaction with DAZAP1 and DAZAP2. The number as well as the precise structure of the DAZ proteins probably differs within the population. The disease may be caused by variants affecting the gene represented in this entry. AZFc deletions in the Yq11.23 region including the DAZ genes are the most common known genetic cause of human male infertility. The DAZ proteins (DAZ, DAZ2, DAZ4 and DAZ4) are all encoded by a strongly repeated region of the Y chromosome, in two clusters each comprising an inverted pair of DAZ genes. They are very similar, which gives their indidual characterization difficult. Thus, most experiments do not discriminate between the different members. One can therefore suppose that reported interactions with a DAZ protein involve all the 4 proteins. Belongs to the RRM DAZ family.