鹿茸再生关键组织角柄骨膜基因组DNA甲基化分析

Analysis of Genome-wide DNA Methylation in the Key Tissue (Pedicle Periosteum) for Antler Regeneration of Sika Deer

为研究鹿茸再生过程中的分子调控机制,利用荧光标记的甲基化敏感扩增多态性(Fluorescence-labeled methylation sensitive amplified polymorphism,F-MSAP)方法,分别从组织和细胞水平检测致敏区角柄骨膜(Potentiated pedicle periosteum,PPP)和休眠区角柄骨膜(Dormant pedicle periosteum,DPP)的基因组DNA甲基化水平。结果表明:无论在组织还是细胞水平,PPP的DNA甲基化水平均低于DPP,并且差异显著(P<0.05)。通过人工制造致敏区角柄骨膜(artificial PPP,a PPP)对试验结果进行了功能验证,证明鹿茸再生过程中,DNA甲基化是重要的分子调控机制,DNA去甲基化是激活鹿茸角柄骨膜再生能力的先决条件。

Deer antlers are the only mammalian appendages that can fully regenerate each year from the permanent bony protuberances of the frontal bones,called pedicles. Pedicle periosteum（ PP） is the key tissue for antler regeneration and the source of antler stem cells. The distal 1/3 of the PP has acquired the ability to regenerate antlers and is termed the potentiated PP（ PPP）,whereas the proximal 2/3 of the PP requires further interactions within its niche to launch antler regeneration,and is termed the dormant PP（ DPP）. However,the molecular mechanisms underlying the process of antler regeneration are unknown. In this study,we used the fluorescence-labeled methylation-sensitive amplified polymorphism method to assess the levels of DNA methylation in both cells and tissues of the PPP and the DPP. The results showed that the levels of DNA methylation were significantly lower in the PPP compared to the DPP（ P0. 05）. Therefore,DNA methylation may be involved in the process of antler regeneration. This involvement was further confirmed by functionaltesting by artificially creating a potentiated PP（ a PPP） from DPP tissue. Our data suggest that DNA methylation plays an important role in antler regeneration,and DNA demethylation is a prerequisite step for the initiation of antler regeneration,and provides the first experimental evidence to link epigenetic regulation and mammalian appendage regeneration.