Chapter 3 Protein Synthesis During Amphibian Metamorphosis

Abstract

This chapter discusses the advantages of studying the biochemical processes in amphibian metamorphosis as a model for studying the regulation in late embryonic development. Not only are the embryos free-living, but also the artificial induction of metamorphosis, by thyroid hormones, at the developmental stages, well before spontaneous metamorphosis, have made it possible to establish a sequence of events preceding the acquisition of the adult functions and structures. Among the earliest responses of target cells is a readjustment of the permeability barriers to a variety of nutrients and precursors of macromolecules. However, the eventual specificity of the developmental changes is most likely to reside in the nature of new or additional species of RNA and protein molecules formed. Due to a combination of the complexity of nuclear RNA, the high degree of nuclear restriction of the rapidly turning over nuclear RNA and the inadequacies of the currently available analytical techniques has not been possible to relate to the burst of RNA synthesis, with selective gene activation at the onset of metamorphosis.