FUNCTIONAL CLONING OF DNA AND RNA BINDING PROTEINS

在我们目前对人类肿瘤发生的理解中，一个新兴的主题是癌症是随着个体细胞中的突变和表观遗传改变的积累而产生的。这种改变的最终结果是改变基因组的表达谱。了解在特定类型的癌症中表达改变的基因的身份和功能，将使特定基因和途径与独特的癌症诱导表型之间的相关性成为可能。这些信息将有助于我们对癌症生物学的理解，并将为癌症检测提供新的生物标志物，以及为治疗策略提供新的基因靶点。因此，当前癌症研究的重中之重是揭示区分癌细胞与野生型的分子变异，并确定受影响基因的功能。在表达改变可能标志着癌症分子特征的基因中，主要候选基因包括那些编码调节基因组表达并催化其复制和修复的蛋白质的基因，统称为核酸结合蛋白（nbp）。维持基因组的完整性和调节其适当的表达是必须控制的重要的第一级细胞内过程。由于癌症等遗传疾病可能是由于基因组的改变而导致的，而基因组的改变最终改变了在核酸保存和调节功能中起作用的基因的表达谱，因此我们在本提案的R21阶段的第一个目标是研究开发一种功能基因组学技术的可行性，该技术旨在通过编码与DNA和/或RNA结合的蛋白质的能力来识别人类基因。该技术的几个附加组件将在提案的R33扩展开发阶段得到解决。其中一个包括一个新的分类阶段，该阶段将根据nbp对特定核酸类型和构象的（编码）结合特性快速区分不同类别的nbp。我们还将开发生物信息学工具，可用于虚拟和基于微阵列的表达谱分析，以确定所选基因或基因簇的表达是否在正常与特定癌细胞中发生改变。一旦开发成功，这项新技术将使维持和调节基因组的基因的功能鉴定、分类和表达谱成为可能。它将直接提高癌症基因组解剖计划（CGAP）的数据质量，并且当细胞内的相对表达发生改变时，它可能会识别出赋予癌症易感性的新基因。这种技术目前还不存在。

An emerging theme in our current understanding of human oncogenesis is that cancers arise as mutations and epigenetic alterations accumulate in individual cells. The ultimate consequence of such changes is to alter the expression profile of the genome. Knowledge of the identity and function of genes whose expression is altered in particular types of cancer, would enable the correlation of specific genes and pathways to unique cancer induced phenotypes. This information would help our understanding of cancer biology and would provide new biomarkers for cancer detection as well as novel gene targets for therapeutic strategies. Thus, a high priority of current cancer research is to reveal the molecular variations that distinguish cancer cells from wild type and to determine the function of the affected genes. Of the possible genes whose altered expression may mark the molecular signature of cancer, primary candidates include those that encode proteins that function to regulate the expression of the genome and catalyze its replication and repair, collectively referred to as nucleic acid binding proteins (NBPs). Maintaining the integrity of the genome and regulating its appropriate expression are important first tier intracellular processes that must be controlled. Since genetic diseases such as cancer can result from alterations in the genome which ultimately change the expression profile of genes that function in nucleic acid house keeping and regulatory functions, our first goal, in the R21 phase of this proposal, is to examine the feasibility of developing a functional genomics technology aimed at identifying human genes selected by their ability to encode proteins that bind to DNA and/or RNA. Several additional components of the technology will be addressed in the R33 expanded development phase of the proposal. One encompasses a novel sorting phase that will rapidly distinguish between different classes of NBPs according to their (encoded) binding properties for particular nucleic acids types and conformations. We will also develop bioinformatic tools that can be used in both virtual and microarray based expression profiling to sample whether the expression of selected genes or gene clusters is altered in normal versus specific cancer cells. When developed, this new technology will enable the functional identification, categorization and expression profiling of genes that act to maintain and regulate the genome. It will directly improve the quality of data in the Cancer Genome Anatomy Project (CGAP) and it will likely identify new genes that confer a predisposition for cancer when their relative expression within a cell is altered. Such technology does not presently exist.