Comprehensive analyses of hox gene expression in Xenopus laevis embryos and adult tissues

From whole genome sequencing of an allotetraploid frog, Xenopus laevis, two homeologous sets (L and S) of four Hox clusters A through D (HoxA.L/S, HoxB.L/S, HoxC.L/S, and HoxD.L/S) and 13 paralogous groups (PGs) with 76 genes were identified, allowing us to carry out the first comprehensive analyses of hox gene expression in vertebrates. Expression of all hox genes during development and in adult tissues was analyzed by RNA‐sequencing. The expression levels of most hox genes were similar between homeologs, but in some pairs, large differences were observed and several of these were confirmed by RT‐PCR and whole mount in situ hybridization experiments. These results indicate that subfunctionalization of hox genes may have occurred since allotetraploidization. Furthermore, comprehensive analysis of hox gene expression during early development did not agree with the hypothesis of temporal collinearity especially in genes belonging to PG2 to PG10.

Expression of all 76 hox genes of Xenopus laevis in eight Hox clusters was analyzed by RNA‐sequencing during development and in adult tissues. In some pairs of homeologous genes, large differences in expression were observed, indicating subfunctionalization of hox genes since allotetraploidization. Comprehensive analysis of hox gene expression during early development did not agree with the hypothesis of temporal collinearity especially in genes belonging to PG2 to PG10.

Source: Development, Growth and Differentiation - June 1, 2017 Category: Research Authors: Mariko Kondo, Takayoshi Yamamoto, Shuji Takahashi, Masanori Taira Tags: Original Article Source Type: research