Creation of mouse strains for the study of hematopoiesis

描述（由申请人提供）：人类和小鼠DNA序列的可用性预示着生物学的新时代。这些数据正在产生所有人类和小鼠基因的结构细节。我们解释和使用这些数据的能力取决于我们评估整个生物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，小鼠构成了首要的模型。在小鼠中，可以使用乙基亚硝基脲（ENU）在生殖系中诱导随机点突变。小鼠的ENU诱变，随后筛选特定表型，允许分离携带导致偏离正常功能的单基因突变的菌株。这一点，再加上强大的突变基因鉴定方法，允许识别基因，调节复杂的生物过程。由于突变是单碱基对变化，因此产生的等位基因通常是功能部分丧失的等位基因，因此不可能有冗余的等位基因系列，这可以提供关于基因功能的丰富信息。此外，功能获得性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灵敏度和特异性。我们建议开发小鼠品系，以筛选在特定血细胞区室中发生改变的突变体。我们感兴趣的是调节造血干细胞数量和分化的稳态机制。这是一个受基因控制的复杂过程。事实上，已经有可能确定小鼠品系之间干细胞数量的变异性，并绘制几个有影响力的基因，但到目前为止，还没有确定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，包括筛选血细胞数量和功能的费力性。我们打算产生报告小鼠品系，其将允许通过分析小鼠血清来计数特定血细胞谱系区室。这种菌株的建立将允许筛选具有异常造血的突变体。

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.