Related Experiment Video
Updated: Aug 17, 2026

A Cell Free Assay to Study Chromatin Decondensation at the End of Mitosis
Published on: December 19, 2015
Barrier-to-autointegration factor is required to segregate and enclose chromosomes within the nuclear envelope and
Ayelet Margalit1, Miriam Segura-Totten, Yosef Gruenbaum
1Department of Genetics, Institute of Life Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel.
Abstract:
Barrier-to-autointegration factor (BAF) binds dsDNA, LEM-domain proteins, and lamins. Caenorhabditis elegans BAF requires Ce-lamin and two LEM-domain proteins (Ce-emerin and Ce-MAN1) to localize during nuclear assembly. It was unknown whether Ce-lamin and LEM proteins, in turn, depend on Ce-BAF (mutually dependent structural roles). RNA interference-mediated down-regulation of Ce-BAF caused gross defects in chromosome segregation, chromatin decondensation, and mitotic progression as early as the two-cell stage, and embryos died at the approximately 100-cell stage. Nuclear pores reassembled, whereas Ce-lamin, Ce-emerin, and Ce-MAN1 bound chromatin but remained patchy and disorganized. The nuclear membranes formed but failed to enclose anaphase-bridged chromatin. Time-lapse imaging showed two phenotypes: anaphase-bridged chromatin that eventually resolved, and segregated chromatin that returned to the midzone. Thus, the assembly of BAF, lamins, and LEM-domain proteins is mutually dependent, and is required to capture segregated chromosomes within the nascent nuclear envelope. Embryos that escaped lethality by down-regulation of Ce-BAF grew into sterile adults with misplaced distal tip cells and gonads, further suggesting that mild postembryonic reductions in BAF disrupt tissue-specific functions.
Related Concept Videos
Eukaryotic Compartmentalizations
For example, lysosomes in the animal cells...
Spindle Assembly
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a microtubule array...
Attachment of Sister Chromatids
Separation of Sister Chromatids
At the onset of anaphase, separase, a proteolytic enzyme, is...
The Spindle Assembly Checkpoint
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Disassembly of Intermediate Filaments
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...

