Tdrkh is essential for spermatogenesis and participates in primary piRNA biogenesis in the germline

ABSTRACT: Piwi proteins and their associated piRNAs are essential in the germline where they repress transposition, regulate translation, and guide epigenetic programming. Little is known, however, about the molecular mechanisms through which Piwi proteins and piRNAs mediate these processes. Here, we show that an evolutionarily conserved Tudor and KH-domain containing protein, Tdrkh (a.k.a. Tdrd2), partners with Miwi and Miwi2 in mice via symmetrically dimethylated arginine residues in Miwi and Miwi2. Tdrkh is localized to pi-bodies and piP-bodies and is required for nuclear localization of Miwi2. Genetic deletion of Tdrkh arrests meiosis at the zygotene stage, demethylates Line1 DNA, and up-regulates Line1 transposition, but does not promote apoptosis. Furthermore, Tdrkh mutants have severely reduced levels of mature piRNAs. Specifically, in Tdrkh mutants, piRNAs accumulate as a distinct population of 5’U-containing 31-37nt RNA that largely complements the missing mature piRNAs. These results demonstrate that the primary piRNA biogenesis pathway involves 3à5’ processing of the 31-37nt intermediates and that Tdrkh is required for this final step of piRNA biogenesis. However, Tdrkh is not required for the secondary piRNA biogenesis pathway (i.e., the ping pong cycle). These results shed light on mechanisms underlying primary piRNA biogenesis, an area in which information is conspicuously absent.

ORGANISM(S): Mus musculus

PROVIDER: GSE47151 | GEO | 2013/09/01

SECONDARY ACCESSION(S): PRJNA204938

REPOSITORIES: GEO