CAA: DNA-Protein Interactions Regulating Transcription of the Id Protein Gene During Myogenesis

这项研究得到了NSF职业发展奖的支持， 妇女 这项工作解决了一个最重要的方面之一， 当今分子生物学家面临的重大问题， 动物的分化过程 来自单个受精卵的特殊器官受到调节。 一 这种过程是肌肉形成或肌生成过程。 期间 生肌细胞启动许多基因的表达 其项目是特定于并且对于其职能是必要的 肌肉. 肌肉特异性基因的开启伴随着 下调编码以下基因的基因家族的表达： 其功能似乎是抑制分化的蛋白质， Id或分化抑制蛋白。 Id蛋白质是 并不是肌肉细胞所独有的，有一种假设是Id抑制了 细胞的分化已经提交给一个特定的 发育途径，直到胚胎发生的终末 区分是恰当的。 在培养中，当成肌细胞或前- 肌肉细胞用药物阿霉素处理，然后 将它们放在通常会分化成 肌管或肌细胞，它们不分化。 而是 细胞产生异常高水平的Id mRNA和蛋白质， 在分化过程中应该被打开的基因 关闭. 基因的开启和关闭是由 专门的调节蛋白和特定的DNA序列， 启动子或控制区。 这些实验旨在 确定和比较特定蛋白质-DNA的位点 细胞中Id基因启动子区的相互作用， 在不同水平表达Id，成肌细胞，肌管， 肌肉细胞受到暴露于阿霉素的影响。 “体内 “足迹”将用于确定监管 蛋白质被绑定。 启动子区的核苷酸序列 将被确定，并将被占用的网站与 那些已知结合各种组织特异性和普遍存在的 调节蛋白 为了使任何生物发育过程发生 要想成功，就必须对其进行认真的监管。 分子生物学家 已经成功地发现了一些不同的 控制发育的调节蛋白。 一种这样的蛋白质是 它被称为ID，它的功能之一似乎是保持前- 肌肉细胞变成肌肉组织， 时间在发展。 这项研究的成果将增加 我们对发展错综复杂的认识， 这样做可能会提供一些发展障碍的见解， 当分子控制失败时发生的疾病。

This research is supported by an NSF Career Advancement Award to Women. The work addresses a single aspect of one of the most compelling questions challenging molecular biologists today, that is, how the differentiation processes by which animals develop specialized organs from a single fertilized egg are regulated. One such process is that of muscle formation or myogenesis. During myogenesis, myogenic cells turn on expression of numerous genes whose projects are specific to and necessary for function of muscle. The turning on of muscle specific genes is accompanied by down-regulation of expression of a family of genes which code for proteins whose function appears to be to inhibit differentiation, the Id or Inhibitor of differentiation proteins. Id proteins are not unique to muscle cells and one hypothesis is that Id inhibits the differentiation of cells already commited to a specific developmental pathway until such time in embryogenesis as terminal differentiation is appropriate. In culture, when myoblasts or pre- muscle cells are treated with the drug doxorubicin, and are then placed in medium in which they would normally differentiate into myotubes or muscle cells, they do not differentiate. Instead, the cells produce abnormally high levels of Id mRNA and protein, and the genes which should be turned on during differentiation remain off. Genes are turned on and off by interactions between specialized regulatory proteins and specific DNA sequences in their promoter or control regions. These experiments are designed to determine and compare the sites of specific protein-DNA interactions in the promoter region of the Id gene in cells which are expressing Id at different levels, myoblasts, myotubes, and muscle cells affected by exposure to doxorubicin. "In vivo footprinting" will be used to determine where the regulatory proteins are bound. The nucleotide sequence of the promoter region will be determined, and the occupied sites will be compared to those already known to bind various tissue specific and ubiquitous regulatory proteins. In order for any biological developmental process to occur successfully, it must be carefully regulated. Molecular biologists have been successful at identifying a number of different regulatory proteins which control development. One such protein is called Id, and one of its functions appears to be to keep pre- muscle cells from becoming muscle tissue until exactly the right time in development. The results of this research will increase our appreciation for the intricacies of development, and in so doing may provide insight into some developmental disorders or diseases which occur when molecular controls fail.