NELL-1, A Cbfa1 DOWNSTREAM TARGET, IN BONE FORMATION

NELL-1，Cbfa1 下游靶标，在骨形成中

基本信息

批准号：
7456445
负责人：
KANG TING
金额：
$ 32.6万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-07-01 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7456445
关键词：
Active Sites Affect Biological Assay Bone Growth Calvaria Cells Cephalic Chickens Cleft Lip Cleft Palate Clinical Commit Complement Coupled Coupling Data Defect Development Disruption Distraction Osteogenesis Dominant-Negative Mutation Embryo Epidermal Growth Factor Exhibits Financial compensation Genes Genetic Transcription Human In Vitro Invasive Knock-out Knockout Mice Knowledge Luciferases Mediating Mediator of activation protein Mesenchymal Molecular Mus Natural regeneration Nature Nuclear Extract Numbers Operative Surgical Procedures Osteoblasts Osteocalcin Osteogenesis Patients Phenotype Protein Overexpression Proteins Recombinants Regulation Response Elements Site Site-Directed Mutagenesis Specificity Surgical sutures Testing Therapeutic Tin Tissues Wild Type Mouse Work base bone cell type cis acting element craniofacial craniofacial repair embryonic stem cell in vivo intramembranous bone intramembranous bone formation intramembranous development mineralization preconditioning promoter reconstruction relating to nervous system suture fusion tool vector

项目摘要

DESCRIPTION (provided by applicant): Cbfa1 mediates mesenchymal cell commitment to an osteochondroprogenitor lineage and supports continued differentiation and function in committed osteoblasts. However, definitive downstream mediators of Cbfa1 that critically impact osteoblast differentiation and bone formation have yet to be described. Ne1 (a protein strongly expressed in neural tissue encoding epidermal growth factor like domain) was first identified in chicken embryos. The preliminary data shows that Nell-1 (Ne1-like molecule-1) in vivo is associated with normal and pathological suture fusion, while Nell- 1 in vitro is associated with increased osteoblast differentiation and mineralization. Furthermore, the human Nell-1 promoter contains three osteoblast-specific cis-acting element 2 (OSE2) response elements for Cbfa1 and that Nell-1 overexpression mice can functionally compensate for some aspects of intramembranous bone deficiency in heterozygous Cbfa1 deficient mice. These data have led to the hypothesis that Nell-1 is a central downstream target of Cbfa1 that supports continued differentiation and function in committed osteoblasts and proper Nell-1 expression is required for normal membranous bone growth and formation. To test this hypothesis, this proposal will analyze the following: 1) the regulation of Nell-1 transcription by Cbfa1 during osteoblast formation and function and by Cbfa1 through OSE2 response elements; 2) the functional compensation of Cbfa1 deficiency by Nell-1 in vivo and in vitro; and 3) the effects of targeted Nell-1 disruption in vivo. If Nell-1 is proven to be a critical mediator of intramembranous bone formation, it can further aid in understanding the development of intramembranous vs. endochondral bone. In addition, since sutures are major sites of calvarial intramembranous bone growth the close association of Nell-1 with calvarial sutures can also impact present knowledge on cranial vault development. Lastly, Nell-1 can be tremendously useful as a clinical tool to inhibit or induce intramembranous bone growth, with the secretory nature of Nell-1 making this utility even more feasible. Controlled inhibition of intramembranous bone growth by anti-Nell-1 strategies in CS patients may offer a less invasive, biologically based, therapeutic alternative to radical surgical craniofacial reconstruction. In addition, the ability of Nell- 1 to induce calvarial osteoblast differentiation may be clinically applied to situations where membranous bone formation and regeneration are desirable (e.g., cleft lip or cleft palate repair and craniofacial distraction osteogenesis).

描述（由申请人提供）：CBFA1介导了间充质细胞的承诺对骨软骨生殖器谱系的承诺，并支持持续的分化和功能在固定成骨细胞中。然而，严重影响成骨细胞分化和骨形成的CBFA1的确定下游介质尚待描述。 NE1（在编码表皮生长因子（如域）中强烈表达的蛋白质首次在鸡胚胎中鉴定出来。初步数据表明，体内NELL-1（NE1样分子1）与正常和病理缝合融合有关，而NELL-1的体外体外与成骨细胞分化和矿化的增加有关。此外，人NELL-1启动子包含CBFA1的三个成骨细胞特异性顺式作用元件2（OSE2）响应元件，NELL-1过表达小鼠可以在功能上补偿杂合性CBFA1缺乏障碍小鼠的某些方面的某些方面。这些数据导致了以下假设：NELL-1是CBFA1的中央下游目标，它支持持续的分化和功能在固定成骨细胞中的持续分化和功能，并且需要正常的膜骨生长和形成需要适当的NELL-1表达。为了检验该假设，该提案将分析以下内容：1）在成骨细胞形成和功能期间，CBFA1对NELL-1转录的调节以及通过OSE2响应元素通过CBFA1进行调节； 2）NELL-1在体内和体外的CBFA1缺乏症的功能补偿； 3）靶向NELL-1在体内造成的影响。如果证明NELL-1是膜内骨形成的关键介体，则可以进一步帮助理解膜内与内软骨内骨的发展。此外，由于缝合线是钙质内骨内生长的主要部位，因此NELL-1与钙缝合线的密切关联也会影响当前对颅库发育的知识。最后，NELL-1作为抑制或诱导膜内骨生长的临床工具非常有用，NELL-1的分泌性质使该效用更加可行。 CS患者中抗NELL-1策略对膜内骨内生长的控制抑制可能会提供侵入性较低的基于生物学的基于生物学的，治疗性的替代方法，可替代自由基外科颅面重建。另外，NELL-1诱导颅骨成骨细胞分化的能力可以在临床上应用于膜状骨形成和再生的情况（例如，唇lip或left唇或裂解的修复以及颅面分离的分散分散分散注意力的生成）。