Reconstruction of muscle development as a sequence of macromolecular synthesis.

Abstract

Publisher Summary This chapter hopes to promote progress toward an understanding of muscle development by attempting to integrate the results of the different lines of research. An approximate schedule of the successive steps in the determination of mesodermal tissue that leads to the development of presumptive muscle cells in the limb buds of the chick is elaborated. The chapter outlines the characteristics of this crucial transition period in developing muscle tissue. It begins with the frustrating problem of the first appearance of cell-specific proteins. Two general difficulties in the analysis of developmental processes are encountered. The first of these pertains to the definition of what is meant by specific cell proteins. Perhaps more critical is the second difficulty—defining what is meant by “the first appearance” of a cell-specific protein. The appearance and increase in myosin in skeletal muscle is used as the standard indicator. The overall activity of the transcriptional and translational system is measured as incorporation of amino acids into proteins. The chapter inquires the relationship of protein accumulation to protein synthesis expressed as amino acid incorporation.