Creation of mouse strains for the study of hematopoiesis

描述(申请人提供)：人类和小鼠DNA序列的可获得性预示着生物学的新纪元。这些数据正在产生所有人类和老鼠基因的结构细节。我们解释和使用这些数据的能力取决于我们评估整个有机体内基因功能的能力，这通常是通过研究基因突变来完成的。对于人类疾病的研究，特别是血液疾病的研究，小鼠构成了主要的模型。在小鼠中，使用乙基亚硝脲(ENU)可以在生殖系中诱导随机点突变。对小鼠进行enu突变，然后对特定表型进行筛选，可以分离出携带导致正常功能偏离的单基因突变的菌株。这一点，再加上强大的突变基因识别方法，使得能够识别调控复杂生物过程的基因。由于突变是单碱基对的变化，产生的等位基因往往是部分功能缺失的等位基因，因此不可能有多余的等位基因序列，这可以给出丰富的基因功能信息。此外，功能获得型等位基因也是可能的。ENU诱变的能力完全取决于表型筛选的敏感性和特异性。我们建议开发小鼠品系，使人们能够筛选在特定血细胞室发生变化的突变。我们感兴趣的是调节造血干细胞数量和分化承诺的动态平衡机制。这是一个受基因控制的复杂过程。事实上，已经有可能在小鼠品系中识别干细胞数量的变异性，并绘制出几个有影响的基因，但到目前为止，还没有发现调节干细胞数量的特定基因。到目前为止，所描述的方法受到主要问题的阻碍，包括血细胞数量和功能筛查的繁琐性质。我们打算产生报告小鼠品系，通过对小鼠血清的分析，可以计数特定的血细胞谱系。这种菌株的建立将使人们能够筛选出具有异常造血功能的突变株。

DESCRIPTION (provided by applicant): The availability of DNA sequence for the human and mouse has heralded a new era in biology. These data are yielding structural details for all human and mouse genes. Our ability to interpret and use these data is dependent on our ability to assess gene function within a whole organism, which is typically done through the study of gene mutations. For the study of human disease, especially those of the blood, the mouse constitutes a premier model. In the mouse, it is possible to induce random point mutations in the germline using ethyl nitrosourea (ENU). ENU mutagenesis of mice followed by screens for specific phenotypes allows for the isolation of strains bearing single gene mutations that cause deviation from normal function. This, coupled with robust approaches to mutant gene identification, allows the identification of genes that regulate complex biological processes. Because the mutations are single base pair changes, the alleles generated are very often partial loss of function alleles, and thus no redundant allele series are possible, which can give a wealth of information about gene function. In addition, gain-of-function alleles are also possible. The power of ENU mutagenesis is entirely dependent on the sensitivity and specificity of the phenotypic screen. We propose the development of mouse strains that will allow one to screen for mutants that are altered in particular blood cell compartments. We are interested in the homeostatic mechanisms that regulate hematopoietic stem cell number and commitment to differentiation. This is a complex process that is under genetic control. Indeed, it has been possible to identify variability in stem cell number among mouse strains and to map several influential genes, but as of yet, no specific genes that regulate stem cell number have been identified. The approaches described thus far are hampered by major problems including the laborious nature of screens for blood cell number and function. We intend to generate strains of reporter mice that will allow the enumeration of a specific blood cell lineage compartment through analysis of mouse serum. The establishment of such strains will allow one to screen for mutants that have abnormal hematopoiesis.