Comparison of gene expression profiles between wild-type and Kdm7a mutan embryos

Temporal and spatial colinear expression of Hox genes determines the specification of positional identities of the embryo. Post-translational modifications of histones contribute to transcriptional regulation, and are required for proper control of biological processes, including differentiation and development. Lysine demethylase 7A (Kdm7a) demethylates lysine 9 di-methylation of histone H3 (H3K9me2) and participates in transcriptional activation of developmental genes. However, the role of Kdm7a during mouse embryonic development remains to be elucidated. Here, we show that Kdm7a-/- mice exhibit anterior homeotic transformation of the axial skeleton (i.e. an increase in the number of presacral elements). Importantly, posterior Hox genes (caudally from Hox9) are specifically down-regulated in Kdm7a-/- embryos, which correlate with increased levels of H3K9me2. Taken together, these data suggest that Kdm7a is able to control transcription of posterior Hox genes, likely through its demethylating activity, and thereby regulating anterior-posterior development in mice. Total 12 samples were derived from [1] wild-type E9.5 embryos , [2] Kdm7a mutant E9.5 embryos, [3] wild-type E10.5 embryos, [4] Kdm7a mutant E10.5 embryos (n=3 for each condition).