物理化学および生物物理学ジャーナル
オープンアクセス

概要

The Spherical Reference System of Metazoan Cells

Marco Regolini

Centrioles, through their 9-fold symmetry, circumferential polarity (non-equivalence of their 9 triplets) and orthogonal arrangement, may build a biological interface tool that recognizes topogenic molecular signals and translates them by delivering targeted complexes (polarity and adhesion factors, transmembrane receptors, mRNAs) into their expected locations, precisely connecting, like a wiring device, each targeted complex with the corresponding correctly-oriented microtubule. Through this tool (the centrosome and its aster of robust microtubules) DNA can draw, build and “label” an intrinsic finely tuned 3D grid line of the cell. Counterclockwise circumferential polarity of the mother centriole is the natural candidate to be the molecular basis of Metazoan bilateral symmetry. The following analysis aims to support the idea that there are well known molecular mechanisms capable of realizing the circumferential non-equivalence of the triplets and the reversal orientation of mother centriole rotational polarity: starting from experimental facts (the requirements of a spherical reference system based on two orthogonal protractors show a surprising correspondence with the evidence emerging from numerous experimental studies on centrioles and centrosomes), some plausible hypotheses are formulated (and logical consequent considerations deducted) to show that the proposed geometrical main role of the centrosome has robust and solid biophysical and biochemical foundations.