The function of TEX19 (testis expressed 19, ENSG00000182459) is as follows. Required during spermatogenesis and placenta development, participating in the repression of retrotransposable elements and prevent their mobilization. Collaborates with the Piwi-interacting RNA (piRNA) pathway, which mediates the repression of transposable elements during meiosis by forming complexes composed of piRNAs and Piwi proteins. Interacts with Piwi proteins and directly binds piRNAs, a class of 24 to 30 nucleotide RNAs that are generated by a Dicer- independent mechanism and are primarily derived from transposons and other repeated sequence elements. Also during spermatogenesis, promotes, with UBR2, SPO11-dependent recombination foci to accumulate and drive robust homologous chromosome synapsis (By similarity). Interacts with LINE-1 retrotransposon encoded LIRE1, stimulates LIRE1 polyubiquitination, mediated by UBR2, and degradation, inhibiting LINE- 1 retrotransposon mobilization (PubMed:28806172). .