Cfp1 Action in Cartilage Development

软骨内骨化是间充质祖细胞（MPC）分化成软骨细胞的过程。 在形成骨骼之前，它们分化能力的紊乱导致骨骼异常。 因此，破译控制这些细胞的分子机制对于理解这些细胞的功能至关重要。 研究骨骼疾病的原因以及开发新的治疗方法来恢复骨骼。而 转录因子和信号分子与软骨发育有关，但对 启动该过程的上游机制。最近来自小鼠和人类的数据表明， 调节因子作为MPC功能的关键调节剂。CXXC指蛋白1（Cfp1）是一种表观遗传的 涉及祖细胞功能的调节因子，尽管其作用机制还不清楚。 定义明确。为了解决这个问题，我们删除了Cfp1特别是从肢芽间充质。初步数据显示 Cfp1的缺失导致出生时前肢完全缺失。胚胎的后续分析 前肢显示，在缺乏Cfp1的情况下，MPCs未能进行浓缩，这是细胞分裂的最初步骤。 软骨形成全转录组分析揭示了软骨形成基因标记的显著减少， 包括主转录调节因子Sox 9，它是缩合所必需的，进一步暗示Cfp 1 作为软骨形成早期的关键因素。初步数据表明，Cfp1可能调节 这是通过激活BMP信号传导的关键发育步骤。此外，当突变的后肢形成时， 严重发育不良，这与我们的观察结果一致，即软骨细胞中Cfp 1的缺失导致骨骼变短。 总之，这些数据表明，Cfp 1也调节软骨细胞的分化和成熟， 生长板发育我们假设Cfp 1调节软骨发育的多个阶段 通过调节重要的转录调节因子和关键信号通路。Cfp1的进一步研究 将提供关于细胞和分子机制的表观遗传调控如何影响 软骨形成和生长板发育。我们提出：1）确定Cfp 1在软骨细胞增殖过程中的作用， 2）确定Cfp 1缺失对生长板发育的影响 以及3）鉴定软骨发育过程中Cfp 1的调控网络。

Endochondral ossification is a process by which mesenchymal progenitor cells (MPCs) differentiate into cartilage prior to forming bone. Perturbations in their capacity to differentiate leads to skeletal anomalies. Therefore, deciphering the molecular mechanisms controlling these cells is crucial for both understanding the causes of skeletal diseases as well as developing new therapeutic approaches to restore the skeleton. While transcription factors and signaling molecules have been linked to cartilage development, less is known about the upstream mechanisms that initiate the process. Recent data from mice and humans implicate epigenetic regulatory factors as critical modulators of MPC function. CXXC finger protein 1 (Cfp1) is an epigenetic regulatory factor implicated in progenitor cell function, though the mechanism(s) of its action have not been well defined. To address this, we deleted Cfp1 specifically from limb bud mesenchyme. Preliminary data show that loss of Cfp1 results in the complete absence of forelimbs at birth. Subsequent analysis of embryonic forelimbs revealed that, in the absence of Cfp1, MPCs failed to undergo condensation, the initial step in chondrogenesis. Whole transcriptome analysis revealed a dramatic reduction in chondrogenic gene markers, including the master transcriptional regulator, Sox9, which is required for condensation, further implicating Cfp1 as a crucial factor in the early stages of cartilage formation. Preliminary data indicate that Cfp1 may regulate this key developmental step through activation of BMP signaling. Further, while mutant hindlimbs form they are severely stunted, consistent with our observation that deletion of Cfp1 in chondrocytes results in shorter bones. Together, these data suggest that Cfp1 also regulates chondrocyte differentiation and maturation during growth plate development. We hypothesize that Cfp1 regulates multiple stages of cartilage development through modulation of essential transcriptional regulators and key signaling pathways. Further study of Cfp1 will provide fundamental insight into how epigenetic regulation of cellular and molecular mechanisms impacts chondrogenesis and growth plate development. We propose: 1) to identify Cfp1's actions during chondrocyte differentiation in the developing long bone, 2) to determine the effect of Cfp1 loss on growth plate development and 3) to identify the Cfp1 regulatory network during cartilage development.