MITOTIC SPINDLES AND MICROTUBULE DYNAMICS IN XENOPUS EGG EXTRACTS

During cell division, a transient bipolar structure known as the mitot ic spindle assembles around duplicated chromosomes and segregates one copy of each to two daughter cells. An ideal approach to understanding the morphogenesis and function of mitotic spindles is to reconstitute the process in vitro and then dissect it biochemically. Spindle assem bly and anaphase have been reproduced in vitro in extracts of frog egg s. This system provides a means to characterize principles that underl ie spindle formation, and to address the function of individual protei ns in this complex morphogenetic event.