Dlx5 and Dlx6 can antagonize cell division at the G 1 /S checkpoint

Background Dlx5 and Dlx6 stimulate differentiation of diverse progenitors during embryonic development. Their actions as pro-differentiation transcription factors includes the up-regulation of differentiation markers but the extent to which differentiation may also be stimulated by regulation of the cell cycle has not been addressed. Results We document that expression of Dlx5 and Dlx6 antagonizes cell proliferation in a variety of cell types without inducing apoptosis or promoting cell cycle exit. Rather, a variety of evidence indicates that elevated Dlx5 and Dlx6 expression reduces the proportion of cells in S phase and affects the length of the cell cycle. Conclusions Antagonism of S-phase entry by Dlx5 and Dlx6 proteins likely represents a lineage-independent function to effect Dlx-mediated differentiation in multiple progenitor cell types.