Knowing Your Place

Two papers independently confirm that chromosome arrangements are retained through mammalian cell division and transmission of chromosomal position from mother to daughter might be mediated by controlling the timing of particular chromosomal partitioning during mitosis.

Abstract

CELL BIOLOGY During cell division, replicated chromosomes condense and are separated to daughter cells by the mitotic spindle. The dynamics of chromosome condensation and partitioning has been subjected to much scrutiny. Now two papers, by Gerlich et al . and Walter et al., independently confirm that chromosome arrangements are retained through mammalian cell division. By bleaching fluorescently labeled chromosomes in a variety of living mammalian tissue culture cells just before mitosis, Gerlich et al . revealed that a general retention of the chromosomal localization was maintained—chromosome regions in the “top” of the nucleus stayed at the top, and those at the “bottom” stayed at the bottom. Similarly, Walter et al. used “chromosome painting” to observe that in HeLa cells, the global distribution of chromosomes and chromosomal territories was retained throughout interphase even though during mitosis itself some rearrangements of specific chromosome territories were seen. Transmission of chromosomal position from mother to daughter might be mediated by controlling the timing of particular chromosomal partitioning during mitosis and could be important in maintaining gene expression patterns. — SMH Cell 10.1016/s0092867403001892 (2003); J. Cell Biol . 160 , 685 (2003).