Gametic specialization of centromeric histone paralogs in <i>Drosophila virilis</i>

In most eukaryotes, centromeric histone (CenH3) proteins mediate mitosis and meiosis ensure epigenetic inheritance of centromere identity. We hypothesized that disparate chromatin environments in soma versus germline might impose divergent functional requirements on single CenH3 genes, which could be ameliorated by gene duplications subsequent specialization. Here, we analyzed the cytological localization two recently identified paralogs, Cid1 Cid5, Drosophila virilis using specific antibodies epitope-tagged transgenic strains. find only ancestral is present somatic cells, whereas both Cid5 are expressed testes ovaries. However, lost male but retained throughout oogenesis, during female mature sperm. Following fertilization, detectable early embryo, suggesting maternally deposited rapidly loaded onto paternal centromeres protamine-to-histone transition. Our studies reveal mutually exclusive gametic specialization paralogs. Duplication divergence allow essential genes to resolve an intralocus conflict between maternal many animal species.