Elucidation of the role of Creb5 in promoting the formation and patterning of the intervertebral disc

项目概要/摘要。 脊柱疾病，包括椎间盘退变，小关节综合征和脊柱侧凸，是常见的 疾病椎间盘退变和小关节综合征以及脊柱侧凸， 与慢性腰痛相关/或可能导致慢性腰痛，这是非常常见的，造成更多的全球残疾，而不是 任何其他条件。该项目的广泛，长期目标是全面了解 细胞身份的规范和调节形成和模式的调节网络 椎间盘在脊柱功能中起着关键作用，易受发育性疾病的影响， 退化性疾病和损伤。然而，像关节软骨损伤后，椎间盘细胞不 修复/再生良好。因此，识别转录因子和/或信号分子是至关重要的 决定椎间盘中不同类型的细胞（包括干细胞/祖细胞） 治疗脊柱疾病的策略。我最近的研究结果表明，转录因子Creb 5是 在IVD形成前在椎间间充质细胞中特异性表达;随后在 纤维环中的所有细胞，包括内纤维环（IAF）和外纤维环 在IVD形成后的纤维化（OAF）中表达;并且也在小关节中表达。最重要的是，我发现， 在经工程改造以缺乏Creb 5功能的小鼠中，纤维环细胞的形态显著改变; 并且Prg 4/润滑素和WNT拮抗剂Wif 1（Wnt抑制因子1）的表达显著增加， 在这些小鼠的椎间盘中减少。因此，我的研究结果表明，Creb 5是必要的，以维持 椎间盘的适当形态，并且对于驱动Prg 4/润滑素和 椎间盘中的Wifi 1。与Creb 5在IVD中的重要性一致，全基因组关联 一项研究确定Creb 5是日本青少年特发性脊柱侧凸的易感基因。最近的一 一项全基因组关联研究将Creb 5确定为与退行性变手术相关的易感基因座。 肩袖疾病，这是最常见的渐进性磨损和撕裂的另一个纤维结缔组织 （腱）。由于Creb 5在椎间间充质（IM）中特异性表达， 在椎间盘、小关节和纤维环的所有细胞中，我假设Creb 5起着关键的作用。 在脊柱中的作用，并建议进一步研究Creb 5在脊柱发育中的作用。该项目将 确定Creb 5在脊椎发育阶段和成体阶段的表达模式，将描述Creb 5在脊椎发育过程中的作用。 在脊柱发育过程中表达Creb 5的细胞的命运;并测试Creb 5 HA-CreERt 2小鼠是否可以成为成年小鼠。 具有时间控制以靶向所有成熟纤维环细胞的阶段遗传工具。该项目还将确定 Creb 5调节基因和与椎间盘中的Creb 5结合的染色质调节元件。

Project Summary/Abstract. Spine diseases, including intervertebral disc degeneration, facet joint syndrome, and scoliosis, are common diseases. Both intervertebral disc degeneration and facet joint syndrome, as well as scoliosis, are frequently associated with/or may lead to chronic low back pain, which is very common, causing more global disability than any other condition. The broad, long-term goal of this project is to develop a comprehensive understanding of both the specification of the cell identity and the regulatory network that regulates the formation and patterning of the intervertebral disc, which plays a pivotal role in spinal function and is subject to developmental disease, degenerative disease, and injury. However, like articular cartilage after damage, intervertebral disc cells do not repair/regenerate well. Thus, it’s critical to identify both the transcription factors and/or the signaling molecules that determine different cell types (including stem/progenitors) in the intervertebral disc to develop different strategies to treat spine disease. My recent findings have indicated that the transcription factor Creb5 is specifically expressed in intervertebral mesenchymal cells before IVD formation; is subsequently expressed in all the cells in the annulus fibrosus, including both the inner annulus fibrosus (IAF) and the outer annulus fibrosus (OAF) after IVD formation; and is also expressed in facet joints. Most significantly, I have found that the morphology of the annulus fibrosus cells is significantly altered in mice engineered to lack Creb5 function; and that expression of both Prg4/lubricin and the WNT antagonist Wif1 (Wnt inhibitor factor 1) are dramatically decreased in the intervertebral discs of these mice. Thus, my findings indicate that Creb5 is necessary to maintain the proper morphology of the intervertebral disc, and is critical to drive expression of both Prg4/lubricin and Wif1 in the intervertebral disc. Consistent with the importance of Creb5 in the IVD, a genome-wide association study identified Creb5 as a susceptibility locus for adolescent idiopathic scoliosis in Japan. A more recent genome-wide association study identified Creb5 as a susceptibility locus associated with surgery for degenerative rotator cuff disease, which is most often caused by progressive wear and tear of another fibrous connective tissue (tendon). As Creb5 is specifically expressed in the intervertebral mesenchymal (IM) that gives rise to the intervertebral disc, in facet joints, and in all the cells of annulus fibrosus, I hypothesize that Creb5 plays a critical role in the spine and propose to further investigate the role of Creb5 in spine development. This project will determine the expression pattern of Creb5 during spine development stage and adult stage; will delineate the fate of Creb5-expressing cells during spine development; and test whether Creb5HA-CreERt2 mice can be an adult stage genetic tool with temporal control to target all mature annulus fibrosus cells. This project will also identify both Creb5 regulated genes and chromatin regulatory elements that bind Creb5 in the intervertebral disc.