DEVELOPMENTAL REGULATION OF HUMAN MUSCLE PROTEINS

在人类发展过程中， 肌肉的收缩装置发生变化。因此，截然不同 由多基因家族成员编码的蛋白质存在于 胚胎、新生儿和成年发育阶段的肌肉。 肌肉蛋白亚型的变化发生在细胞的过程中 分化、个体发育和对生理刺激的反应 这些变化对心脏的收缩有明显的影响。 肌肉的属性。复杂的监管机制必须 确定正确的蛋白质在 在正确的时间正确的地点。 肌肉发育过程中基因表达的可塑性是 特别是从数量和多样性上看 肌球蛋白重链蛋白(肌球蛋白)。这是一个重大的进步 人类肌球蛋白在培养物中表达的研究结果 通过使用荧光激活的细胞分选器。现在，纯洁的 原代人体肌肉细胞群可在 人体各发育阶段肌肉组织中的数量 并在文化上有所区别。此外，对人的调节 肌球蛋白基因在异核细胞中的表达可以被监测 融合产品，其中休眠的人类肌肉基因 激活了。基因表达的发育过程 最近在培养的细胞中检测到几个肌球蛋白基因 具有高度敏感性的单抗的人肌肉细胞 以及识别不同人类肌球蛋白的特定试剂。 肌肉基因表达的这些转变现在服从于 生化和分子分析。 这项建议的具体目的是增进我们的了解 人类肌肉蛋白质的发育调控。 为此，在体内表达的人肌球蛋白序列 将在体外进行表征和诱导。发展中的 肌球蛋白基因表达的阶段特异性调控 反式作用因子将在异核体中探索。这个 发育和纤维型特异性肌球蛋白的特异性cDNA 用单抗对其表达进行分析 将被隔离和定性。这种方法应该 最终导致对监管、结构和 肌球蛋白重链基因家族成员在蛋白水平上的功能 在人类发育过程中的分子水平。

During human development the structural components of the contractile apparatus of muscle change. Accordingly, distinct proteins encoded by members of multigene families are present in muscle at embryonic, neonatal and adult stages of development. Changes in muscle protein isoforms occur in the course of cell differentiation, ontogeny, and in response physiological stimuli and these changes have a marked impact on the contractile properties of the muscle. Complex regulatory mechanisms must exist that determine that the correct protein is expressed in the correct place at the correct time. The plasticity of gene expression during muscle development is especially well demonstrated by the number and diversity of myosin heavy chain proteins (myosins). A major advance in the study of the expression of human myosins in culture has resulted from the use of the fluorescence-activated cell sorter. Now, pure populations of primary human muscle cells can be isolated in quantity from muscle tissues at all stages of human development and differentiated in culture. In addition, the regulation of human myosin gene expression can be monitored in heterokaryons, cell fusion products in which dormant human muscle genes are activated. A developmental progression in the expression of several myosin genes has recently been detected in cultured human muscle cells with monoclonal antibodies, highly sensitive and specific reagents that recognize distinct human myosins. These transitions in muscle gene expression are now amenable to a biochemical and molecular analysis. The specific aim of this proposal is to increase our understanding of the developmental regulation of human muscle proteins. Toward this end, the sequence of human myosins expressed in vivo will be characterized and induced in vitro. The developmental regulation of myosin gene expression by putative stage-specific trans-acting factors will be explored in heterokaryons. The cDNAs specific to developmental and fiber-type specific myosins whose expression has been analyzed with monoclonal antibodies will be isolated and characterized. This approach should ultimately lead to the dissection of the regulation, structure and function of members of the myosin heavy chain gene family at a molecular level in the course of human development.