Data from: TSSK6 is required for γH2AX formation and the histone-to-protamine transition during spermiogenesis

Spermiogenesis includes transcriptional silencing, chromatin condensation
and extensive morphological changes as spermatids transform into sperm.
Chromatin condensation involves histone hyperacetylation, transitory DNA
breaks, histone H2AX Ser139 phosphorylation (γH2AX), and replacement of
histones by protamines. Previously, we reported that the spermatid protein
kinase TSSK6 is essential for fertility in mice, but its specific role in
spermiogenesis is unknown. Here, we show that TSSK6 expression is
spatiotemporally coincident with γH2AX formation in nuclei of developing
mouse spermatids. RNA-Seq analysis demonstrates that genetic ablation of
Tssk6 does not impact gene expression or silencing in spermatids. However,
loss of TSSK6 blocks γH2AX formation, even though the timing and level of
the transient DNA breaks is unaltered. Further, Tssk6 KO sperm contained
increased histones H3 and H4, and protamine 2 precursor/intermediate(s)
indicative of a defective histone to protamine transition. These results
demonstrate that TSSK6 is required for γH2AX formation during
spermiogenesis, and also link γH2AX to the histone-to-protamine transition
and male fertility.