Artificial
chromosomes made of beads (2 microns) coated with chromatin nucleate
microtubules that eventually self-organize into spindles. The
experiment is carried out by adding chromatin beads to Xenopus
egg extracts arrested in a "metaphase state". Microtubules
are observed by visualizing the fluorescence emitted by Rhodamine
labelled tubulin molecules added in small amounts to the extracts.
This experiment demonstrates that the microtubules that form the
spindle can be nucleated by chromosomes and not only by centrosomes
as previously thought. Accelerated 25 times. Experiment carried out by Rebecca Heald in Eric Karsenti's laboratory (1994-1996) Heald et al. 1996, Self-Organization of microtubules into bipolar spindles around artificial chromosomes in Xenopus egg extracts, Nature, 382, 420-425. Eric Karsenti link to lab |
