A hypothetical Master Development Program for multi-cellular organisms: Ontogeny and phylogeny

Abstract

An effort was made to design a hypothetical system of gene regulation that would allow for precise and reproducible development of a single eukaryote cell into a multi-cell/clone/tissue organism through internal guidance alone, without external cues or environmental coordinates. The concept was constrained only by chemical feasibility. The result is not consistent with biology as currently interpreted, but it has some interesting features and it is consistent with accepted biological facts. The hypothesis is based on a Master Development Program (i.e., DNA sequences protected by the heterochromatin) that is transcribed into Generation-Specific Control Keys that consist of nuclear messenger RNAs that regulate high-level transcription factor genes (e.g., Hox genes). The execution and evolution of this hypothetical mechanism are discussed as are its implications for evolution and development.