Curvilinear, Three-Dimensional Motion of Chromatin Domains and Nucleoli in Neuronal Interphase Nuclei

Abstract

The term "nuclear rotation" refers to a motion of nucleoli within interphase nuclei of several cell types. No mechanism or function has been ascribed to this phenomenon, and it was unknown whether nuclear structures in addition to nucleoli participate in this motion. Moreover, it was unclear whether nuclear rotation occurs independent of concurrent motion of juxtanuclear cytoplasm. The work reported here presents quantitative evidence, for three-dimensional intranuclear, tandem motion of fluorescently labeled chromatin domains associated with nucleoli and those remote from nucleoli. The results show that such motion is curvilinear, that it is not restricted to nucleoli, and, moreover, that it occurs independently of motion of juxtanuclear, cytoplasmic structures. These results suggest that this motion represents karyoplasmic streaming and its function is to transpose to nuclear pores those chromatin domains actively transcribed.

‘Poking’ microtubules bring about nuclear wriggling to position nuclei

“…A similar phenomenon has been reported a number of times during the past 60 or so years for cultured cells and some cells in the developing brain of the zebra fish embryos (Pomerat, 1953;Bard et al, 1985;De Boni and Mintz, 1986;Albrecht-Buehler, 1986 and1988;Herbomel, 1999). However, the mechanism and significance of nuclear wriggling remained unclear.…”

Chromatin Higher-order Structure and Dynamics

“…8). Early studies tracking changes in location of large segments of chromatin and whole chromosome territories indicated that, when corrected for nuclear rotation, the regions were essentially immobile over distances .0.4 mm (Cremer et al 1982, Diboni and Mintz 1986, Shelby et al 1996. However, more recent work combining higher spatial resolution with in vivo labeling of smaller defined segments of chromatin, revealed a more complex scenario with different regions of chromatin showing very different mobilities.…”

Spatial repositioning of centromeric domains during regrowth of axons in nuclei of murine dorsal root ganglion neuronsin vitro

“…The as-325 sociation of nuclear reorganization with changes in cell function therefore suggests that spatial reorganization of chromatin domains may play a role in the control of gene expression. (De Boni and Mintz, 1986;De Boni, 1994).…”