What is "nuclear matrix"

n. (context biology English) A framework of fibers extending throughout the nucleus of a cell.

In biology, the nuclear matrix is the network of fibres found throughout the inside of a cell nucleus and is somewhat analogous to the cell cytoskeleton. However, in contrast to the cytoskeleton, the nuclear matrix has been proposed to be a highly dynamic structure, perhaps more like a dynamic sponge with open compartments for free diffusion of molecules in the nucleus. The nuclear matrix, along with the nuclear lamina aid in organizing the genetic information within the cell.

The exact function of this matrix is still disputed, and its very existence has recently been called into question. Evidence for such a structure was recognised as long ago as 1948 (Zbarskii and Debov), and consequently many proteins associated with the matrix have been discovered. The presence of intra-cellular proteins is largely indisputable, and it is well recognized that proteins such as the Scaffold, or Matrix Associated Proteins (SAR or MAR) have some role in the organisation of chromatins. There is evidence that the nuclear matrix is involved in regulation of gene expression in Arabidopsis thaliana.