小鼠造血组织卵黄囊与胎肝的基因表达谱初步研究

Gene expression profile of yolk sac and fetal liver in mouse

目的 以C5 7BL/6小鼠胚胎期造血组织卵黄囊与胎肝为对象 ,识别在不同的发育阶段c kit+ 与Sca 1 + 早期造血细胞的变化 ,以及在基因表达水平上的主要特点 ,了解造血组织在原始造血向永久造血转移阶段造血能力变化的机制。方法 用流式细胞仪计数分离到的单个细胞中c kit+ 与Sca 1 + 细胞的比例 ,以总RNA建立的cDNA文库通过随机测序的方法 ,识别这些细胞总体的基因表达情况。结果 随胚胎发育 ,卵黄囊和胎肝中的Sca 1 + 细胞比例逐步升高 ,交配后 9～ 1 2d卵黄囊Sca 1 + 细胞比例为 0 .2 4 %～ 2 .5 0 % ,而卵黄囊中c kit+ 细胞的比例有明显下降 ,交配后 9～ 1 2d卵黄囊c kit+ 细胞比例为 6 .1 0 %～ 1 .77% ;对交配后第 9天和第 1 2天的卵黄囊和交配后第 1 2天的胎肝 3个文库的部分基因测序 ,识别的已知功能基因显示表达量较高的基因为各型珠蛋白 ,且以胚胎型为主。结论 细胞表面标志和基因表达的水平测定显示胚胎期的红系造血相对较为活跃 ;

Objective To better understand the mechanisms of the fetal hematopoiesis turn over from primitive to definitive hematopoiesis through the expression level of c kit + and sca 1 + , and major characters of gene expression profile of these cells. Methods c kit and sca 1 expression level were monitored with fluorescence activated cell sorting (FACS) of the mononuclear cells from mouse yolk sac and fetal liver, while gene expression profile was carried out with EST sequencing strategy. Results The Sca 1 + cells were increased while the c kit + cells decreased with the embryonic development. Through profiling the functionally identified known genes, most of the highly expressed were globin genes, especially of embryonic types. Conclusion The erythropoiesis played a key role in early fetal hematopoiesis in mammalian.