The Molecular Mechanism of Morphogenesis: a Theory of Location DNA

A. M. Olovnikov¹

¹Institute of Biochemical Physics, Russian Academy of Sciences, ul. Chernahovskogo 5-94, Moscow, 125319 Russia; E-mail: am@olovnikov.msk.ru

Submitted September 17, 1996.

---

A molecular mechanism whereby cells read positional information during morphogenesis and regeneration is proposed. This mechanism enables the cells to translate the linear genomic information into three-dimensional shapes of the body. The mechanism uses a new DNA fraction called location DNA; this term replaces the former "egoistic" DNA. Domains formed by this DNA and packaged by means of lipid-containing bridges are selectively unpackaged in the gradient of an inductor whose concentration is positively correlated with generation of free radicals in the cell. Free radicals selectively destroy the lipid bridges; individual bridges display various degrees of resistance to oxidative destruction. Therefore, domains of location DNA are selectively decompacted and activated so that the position information can be read out. The epigenetic memory on the achieved state of cellular determination is based on triplexation, that is, the formation of a triplex consisting of a signal RNA molecule and a nascent double-stranded DNA molecule during lagging DNA strand synthesis or DNA repair synthesis. A telomeric element (the chronomere) of postmitotic neurons, due to DNA end underrepair synthesis, allows the organisms to measure the flow of biological time. The length of the chronomere indicates the biological age of the body.

---

KEY WORDS: positional information, epigenetic memory, determination, biological time, free radicals, junk DNA, lipids, telomere, triplex.

---