Novel Subunit of NF-kB Confers Gene Regulatory Specificity

转录因子NF-kB广泛调节大量基因，并参与癌症和 炎症性疾病。异常的组成性NF-κ B激活已被认为是一个关键的致病因素 在癌症和炎症性疾病中。我们的长期目标是阐明控制特异性 NF-κ B靶基因的表达。具体的假设是，NF-κ B DNA结合复合物含有 新的成分，除了Rel二聚体和这些介导特定的基因调控。我们基于 1）核提取物中天然NF-kB的原始大小估计> 200 kD，但当用纯化的p50和p65蛋白重建时，估计其为115 kD，这将是 适合于简单的异二聚体，2）来自纯化蛋白质的重构异二聚体具有> 100倍的 3）我们最近发现核糖体蛋白S3（RPS 3）是一种新的组分， 在NF-κ B DNA结合复合物中介导选择性基因调控。这个实验的重点是 我们的建议是鉴定NFTkB的新亚基并确定Rgl的生化功能。 - 是的具体目标是：1.阐明RPS 3介导的NF-kB靶向特异性的机制 基因调控; 2.鉴定NF-κ B DNA结合复合物中的新组分， 基因表达。我们将纯化CD 25 kB DNA结合复合物中的新组分，阐明其分子结构， 在正常和非正常条件下， 3、开发体内模型并设计靶向RPS 3的新型小肽和新的靶向RPS 3的新型小肽; NF-kB DNA结合复合物中的组分特异性地抑制NF-kB基因。我们将绘制最小的 部分p65，RPS 3和新的组成部分的物理相互作用和NF-κ B的功能，并评估 靶向这些最小部分的细胞渗透性肽的抑制能力。该项目将提供新的 深入了解NF-kB和更好地了解NF-kB的调节特异性。这些结果也将 为治疗癌症和炎性疾病提供了潜在的新的治疗靶点，并且可以 通常与NF-κ B相关疾病有关。

The transcription factor NF-kB extensively regulates a plethora of genes and is involved in cancer and inflammatory disease. Aberrant constitutive NF-kB activation has been recognized as a critical pathogenetic in cancer and inflammatory disease. Our long-term goal is to elucidate the mechanism controlling specific expression of NF-kB target genes. The specific hypothesis is that NF-kB DNA binding complexes contain novel components, besides the Rel dimer and these mediate specific gene regulation. We based that hypothesis on the observations 1) the original size estimate of native NF-kB in nuclear extracts was > 200 kD, but when reconstituted from purified p50 and p65 proteins, it was estimated to be 115 kD which would be appropriate for a simple heterodimer, 2) reconstituted heterodimers from purified proteins have a > 100 fold lower affinity than native NF-kB, 3) our recent finding that ribosomal protein S3 (RPS3) is a novel component in NF-kB DNA binding complexes that mediates selective gene regulation. The experimental focus of this proposal is to identify the novel subupjtsgfNFTkB andsto define the biochemical function of rion-Rgl ^ suburiits. The specific aims are: 1. to elucidate the mechanism of RPS3-mediated specificity in NF-kB target gene regulation; 2. to identify novel component(s) in NF-kB DNA binding complexes that mediated specific gene expression. We will purify the novel components in CD25 kB DNA binding complex, elucidate the functional significance and mechanism of novel components in NF-kB signaling under normal and pathological settings; 3, to develop in vivo models and design novel small peptides targeting RPS3 and novel components in NF-kB DNA binding complexes to specifically irihibitor NF-kB genes. We will map the minimal parts in p65, RPS3 and novel components for physical interaction and NF-kB function and assess the inhibitory capability of cell-permeable peptides targeting at these minimal parts. This project will provide new insight into NF-kB and better our understanding of the regulatory specificity of NF-kB. These results will also provide potential novel therapeutic targets for the treatment of cancer and inflammatory disease, and may have implication for NF-kB-related diseases in general.