Mitotic spindle organization by the preprophase band

J. Christian Ambrose, Richard Cyr

Research output: Contribution to journalArticlepeer-review

51 Scopus citations


In higher plants, the preprophase band (PPB) of microtubules (MTs) forecasts the cell division site prior to mitosis and specifies the organization of MTs into a bipolar prophase spindle surrounding the nucleus. However, the mechanisms governing this PPB-dependent establishment of bipolarity are unclear. Here, we present evidence from live cell imaging studies that suggest a role for the MTs bridging the PPB and the prophase nucleus in mediating this function. Results from drug treatments, along with genetic evidence from null kinesin plants, suggest that these MTs contribute to the bipolarity, orientation, and position of the prophase spindle. Specifically, the absence of these bridge MTs is associated with lack of bipolarity, while non-uniform distributions of bridge MTs correlate with prophase spindle migration, deformation, and enhanced bipolarity toward the region of highest bridge MT density. This behavior does not require actomyosin-based forces, and is enhanced by suppressing MT dynamics with taxol. These observations occur during late prophase, and are coincident with the gradual closing of annular spindle poles. Based on these data, we describe a hypothetical mechanism for bridge MT-dependent organization of prophase spindles.

Original languageEnglish (US)
Pages (from-to)950-960
Number of pages11
JournalMolecular plant
Issue number6
StatePublished - Nov 2008

All Science Journal Classification (ASJC) codes

  • Molecular Biology
  • Plant Science


Dive into the research topics of 'Mitotic spindle organization by the preprophase band'. Together they form a unique fingerprint.

Cite this