Nuclear Matrix - Justification of The Nuclear Matrix Hypothesis

Justification of The Nuclear Matrix Hypothesis

For a long time the question whether a polymer meshwork, a “nuclear matrix” or “nuclear-scaffold” is an essential component of the in vivo nuclear architecture has remained a matter of debate. While there are arguments that the relative position of chromosome territories (CTs), the equivalent of condensed metaphase chromosomes at interphase, may be maintained due to steric hindrance or electrostatic repulsion forces between the apparently highly structured CT surfaces, this concept has to be reconciled with observations according to which cells treated with the classical matrix-extraction procedures maintain defined territories up to the point where a minor subset of acidic nuclear matrix proteins is released – very likely those proteins that governed their association with the nuclear skeleton.

S/MARs (scaffold/matrix attachment elements), the DNA regions that are thought to attach genomic DNA to the nuclear skeleton, show an ever increasing spectrum of established biological activities. All these activities are in agreement with (or most easily explained by) the nuclear matrix hypothesis. This is one justification for maintaining this concept before equally plausible alternative models emerge.

S/MARs find increasing use for the rational design of vectors with widespread use in gene therapy and biotechnology. Nowadays S/MAR functions can be modulated, improved and custom-tailored to the specific needs of novel vector systems.

• See also: minicircle