ABSTRACT
Abstract 335 15.1 Introduction: Supramolecular Preformed Structure Is Important
in Cell Heredity 336 15.2 DNA and Membrane Heredity Compared 336 15.3 The Membranome: Genetic Membranes and the Determinants of
Membrane Identity 339 15.4 Stasis and Quantum Changes in the Membranome during Megaevolution 342 15.5 Lipid Targeting and Membrane Polarity 344 15.6 Biogenesis of Multiple Membrane Systems as an Epigenetic Constraint
on Evolution 346 15.7 Membranes, Cell Skeletons and Genomes Interact to Build and
Maintain Organisms 346 15.8 Envoi 347 References 348
Cells are organisms created by cooperating membranes, chromosomes, skeletons and geneencoded catalysts. Genetic information is transmitted intramolecularly by DNA replication and repair and supramolecularly by membrane heredity. All genes and membranes stem ultimately from those of precellular organisms, probably inside-out cells or obcells, the putative ancestors of the last common ancestor of life, probably a green bacterium with a murein exoskeleton responsible for osmotic stability and helping faithful DNA segregation and cell division. Membrane heredity is mediated by molecular complementarity of proteins that define membrane identity through their key roles in targeting membrane proteins. Membrane polarity and topology and membrane protein and lipid composition are the key features transmitted by membrane heredity. Loss and gain of discrete genetic membranes are very rare evolutionary events that change the membranome — the set of topologically and compositionally distinct membranes of a cell. Gain involves origin of novel targeting
machinery and can occur autogenously by membrane subdivision or symbiogenetically by enslaving a foreign cell and recruiting some or all its genetic membranes and genomes. Intricately interconnected features of multiple membrane morphogenesis impose exceptional epigenetic constraints on cell evolution. Cell architecture, anatomy and genetic viability depend on proper targeting of integral membrane proteins that bind to the bacterial exoskeleton (wall) or eukaryotic cytoskeleton.
