The regulation of keratinocyte stem cells

描述（由申请人提供）：角质形成细胞干细胞在维持表皮和毛囊的正常结构和功能方面具有毋庸置疑的作用，并且被认为是遗传性和获得性皮肤病的重要参与者。因此，鉴定调控其数量和增殖潜力的基因是皮肤生物学中的关键问题。我们在这里提出了一种新的策略，用于识别参与角质形成干细胞调控的基因。该策略利用了我们实验室最近取得的几项重要进展：1）毛囊干细胞选择性标记的鉴定，2）克隆性角质形成细胞干细胞体外检测的灵敏度和定量的发展，3）与干细胞数量相关的几个基因座的遗传作图，以及干细胞基因表达的分析，和4）角质形成细胞干细胞基因表达的分析。这项研究的目的是确定调节角质形成干细胞数量的主要基因。我们的假设是，有特定的基因和途径，调节角质形成细胞干细胞的数量，可能不同于那些调节transit-amplifying细胞的特定目标1的重点是使用遗传工具来完善我们已经确定的连锁区间。在具体目标2中，我们将使用候选基因方法进行干细胞基因鉴定;包括已经鉴定的Bmps基因中序列变体的功能意义。在目标3中，我们将使用一个互补的全球基因组的方法来确定相关的分子途径，并评估在数量性状基因座内的编码序列差异的情况下，引起基因表达差异的调节多态性。我们在这项建议中详细的调查将使角质形成干细胞的主要基因和调控途径的鉴定。这项研究将影响皮肤生物学和干细胞研究领域，并应提供新的见解皮肤致癌机制。干细胞调控基因的鉴定对于基因治疗以及对于慢性过度增殖性皮肤病、不愈合的伤口和皮肤癌的新治疗方式的设计是重要的。

DESCRIPTION (provided by applicant): Keratinocyte stem cells have an unquestioned role in maintaining the normal structure and function of the epidermis and hair follicles and are thought to be important players in inherited and acquired skin disease. Hence, identification of genes regulating their number and proliferative potential is a critical problem in cutaneous biology. We propose here a novel strategy for identifying genes involved in keratinocyte stem cell regulation. This strategy takes advantage of several recent important advances made in our laboratory: 1) identification of a selectable marker on hair follicle stem cells, 2) development of a sensitive and quantitative in vitro assay for clonogenic keratinocyte stem cells, 3) genetic mapping of several loci with linkage to stem cell number analysis of stem cell gene expression, and 4) analysis of keratinocyte stem cell gene expression. The objective of this proposed research is to identify major genes regulating the number of keratinocyte stem cells. Our hypothesis is that there are specific genes and pathways that regulate the number of keratinocyte stem cells that may be different from those regulating transit-amplifying cells The focus of Specific Aim 1 is to use genetic tools to refine the linkage intervals we have already identified. In Specific Aim 2 we will use a candidate gene approach for stem cell gene identification; including the functional significance of the sequence variant in the Bmps gene already identified. In Aim 3, we will use a complementary global genomic approach to identify associated molecular pathways, and to assess regulatory polymorphisms causing differences in gene expression in the absence of coding sequence differences within the quantitative trait locus. The investigation we detail in this proposal will enable the identification of major genes and regulatory pathways in keratinocyte stem cells. This research will impact the fields of cutaneous biology and stem cell research and should provide new insight into the mechanism of skin carcinogenesis. Identification of stem cell regulatory genes is important for gene therapy as well as for the design of new therapeutic modalities for chronic hyperproliferative skin disease, for wound that do not heal, and for skin cancer.