Researchers from the Institute for Research in Biomedicine have identified the histone BigH1 as a key protein in stem cell differentiation to male sex cells. The work was published yesterday in Cell Reports.
Depending on the stage of the process, BigH1 is either present and represses specific genes or it is inhibited to allow gene expression. This allows differentiation and the production of adult sex cells. If this balance is loss, male Drosophila melanogaster show gonadal malformations and infertility.
"We hypothesize that BigH1 represses the genes that are not specific to the germline (when stem cells give rise to sex cells). But we now have to unravel how it does this and how it is activated and silenced," says group leader Ferran Azorín.
"The histone BigH1, which we have studied in Drosophila melanogaster, shows most resemblance to the germline variant of human females but it also shows some similarities to variants of the male germ line," explains first author Albert Carbonell. "Because of these similarities, our work can contribute to our understanding of sex cell differentiation in humans and help to explain some types of infertility.”
The lab is now looking at BigH1 during the differentiation of female sex cells. "We know that this histone is essential, but we assume it will have a distinct role since the process involving female sex cells is considerably different to that of male ones," says Paula Climent, one of the authors on the paper.