Metabolic gradients and morphological polarization in embryonic development of hydroid polypes

• Published in: Development (Cambridge) Vol. 22; no. 3; pp. 431 - 447
• Main Authors: Belousov, L V, Ostroumova, T V
• Format: Journal Article
• Language: English
• Published: England Cambridge University Press for The Company of Biologists Limited 01.11.1969
• Subjects: Animals; Autoradiography; Cell Nucleus - metabolism; Cnidaria - embryology; Cnidaria - growth & development; Cnidaria - metabolism; Cytoplasm - metabolism; Female; Lysine - metabolism; Morphogenesis; Ovum - growth & development; Ovum - metabolism; Oxidation-Reduction; Respiration; Tritium; Uridine - metabolism
• ISSN: 0950-1991; 0022-0752; 1477-9129
• DOI: 10.1242/dev.22.3.431

One of the main problems of modern embryology is the problem of relations between morphogenetic and metabolic processes. For several decades this problem was studied under the influence of the theory of physiological gradients and of some of its modifications (Child, 1941; Dalcq & Pasteels, 1938). The general principle of these conceptions was that the processes of cell differentiation were strictly determined by previous regional metabolic conditions (metabolic, or physiological gradients). The gradients were supposed in their turn to be determined by the heterogeneity of the embryo's environment. Therefore, a simple and non-reversible chain of relationships was postulated: heterogeneity of environment → graded metabolic differences → regional differences at the cellular or supracellular levels. No possibility of any kind of inverse relations—that is, influence of cellular and supracellular events upon the metabolic processes—was taken into account in these conceptions. More recently however a number of facts were obtained which demonstrate the possibility of reverse relations.