Hoxc4 chromatin is activated

Hoxc4 is expressed in embryos at E12.5 caudal to rhombomere 7 (r7, Geada et al. 1992). Hoxc4 is also expressed at the level of prevertebrae 4-5, in spinal column, esophagus, lung, trachea, and metanephric kidney (Geada et al. 1992). Vitamin A (and hence retinoic acid) appears to induce expression of Hoxc4 (Liu and Zhu 2000). Hoxc4 is induced by beta-catenin during neurogenesis of embryonic stem cells (Otero et al. 2004). Chromatin at Hoxc4 loses methylation at lysine-27 of histone H3 (H3K27me3), loses polycomb repressive complex 2 (PRC2), and gains methylation at lysine-4 of histone H3 (H3K4me3) during treatment of embryonic stem cells with retinoic acid (Mazzoni et al. 2013).

Hoxc4基因在胚胎E12.5期于菱形7区（r7，Geada等，1992年）后方表达。此外，Hoxc4亦在脊椎、食管、肺、气管和后肾中表达（Geada等，1992年）。维生素A（进而为视黄酸）似乎可诱导Hoxc4的表达（Liu和Zhu，2000年）。在胚胎干细胞的神经发生过程中，Hoxc4受到β-连环蛋白的诱导（Otero等，2004年）。在用视黄酸处理胚胎干细胞的过程中，Hoxc4的染色质在组蛋白H3的赖氨酸-27位（H3K27me3）去甲基化，失去多梳抑制复合体2（PRC2），并在组蛋白H3的赖氨酸-4位（H3K4me3）甲基化（Mazzoni等，2013年）。