Kondo Mariko, Yamamoto Takayoshi, Takahashi Shuji, Taira Masanori
Misaki Marine Biological Station, Graduate School of Science and Center for Marine Biology, The University of Tokyo, 1024 Koajiro Misaki, Miura, Kanagawa, 238-0225, Japan.
Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Dev Growth Differ. 2017 Aug;59(6):526-539. doi: 10.1111/dgd.12382. Epub 2017 Aug 9.
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.
通过对异源四倍体青蛙非洲爪蟾进行全基因组测序，鉴定出了四个Hox基因簇A至D的两个同源基因组（L和S）（HoxA.L/S、HoxB.L/S、HoxC.L/S和HoxD.L/S）以及13个旁系同源组（PGs）中的76个基因，这使我们能够对脊椎动物中的hox基因表达进行首次全面分析。通过RNA测序分析了所有hox基因在发育过程中和成年组织中的表达。大多数hox基因在同源基因之间的表达水平相似，但在某些基因对中观察到了较大差异，其中一些通过RT-PCR和整体原位杂交实验得到了证实。这些结果表明，自异源四倍体化以来，hox基因可能发生了亚功能化。此外，对早期发育过程中hox基因表达的综合分析与时间共线性假说不一致，特别是在属于PG2至PG10的基因中。
