Vv. Philimonenko et al., The nucleoskeleton: A permanent structure ct cell nuclei regardless of their transcriptional activity, EXP CELL RE, 264(2), 2001, pp. 201-210
Nuclear matrix or nucleoskeleton is thought to provide structural basis for
intranuclear order. However, the nature of this structure is still uncerta
in because of numerous technical difficulties in its visualization. To reve
al the "real" morphology of the nucleoskeleton, and to identify possible so
urces of structural artifacts, three methods of nucleoskeleton preparations
were compared. The nucleoskeleton visualized by all these techniques consi
sts of identical elements: nuclear lamina and an inner network comprising c
ore filaments and the "diffuse" nucleoskeleton. We then tested if the nucle
oskeleton is a stable structure or a transient transcription-dependent stru
cture. Incubation with transcription inhibitors (cu-amanitin, actinomycin D
, and DRB) for various periods of time had no obvious effect on the morphol
ogy of the nucleoskeleton. A typical nucleoskeleton structure was observed
also in a physiological model - in transcriptionally inactive mouse 2-cell
embryos and in active 8- to 16-cell embryos. Our data suggest that the nucl
eoskeleton is a permanent structure of the cell nucleus regardless of the n
uclear transcriptional state, and the principal architecture of the nucleos
keleton is identical throughout the interphase. (C) 2001 Academic Press.