Arabidopsis TANGLED identifies the division plane throughout mitosis and cytokinesis

Curr Biol. 2007 Nov 6;17(21):1827-36. doi: 10.1016/j.cub.2007.09.063. Epub 2007 Oct 25.

Abstract

Background: In premitotic plant cells, the future division plane is predicted by a cortical ring of microtubules and F-actin called the preprophase band (PPB). The PPB persists throughout prophase, but is disassembled upon nuclear-envelope breakdown as the mitotic spindle forms. Following nuclear division, a cytokinetic phragmoplast forms between the daughter nuclei and expands laterally to attach the new cell wall at the former PPB site. A variety of observations suggest that expanding phragmoplasts are actively guided to the former PPB site, but little is known about how plant cells "remember" this site after PPB disassembly.

Results: In premitotic plant cells, Arabidopsis TANGLED fused to YFP (AtTAN::YFP) colocalizes at the future division plane with PPBs. Strikingly, cortical AtTAN::YFP rings persist after PPB disassembly, marking the division plane throughout mitosis and cytokinesis. The AtTAN::YFP ring is relatively broad during preprophase/prophase and mitosis; narrows to become a sharper, more punctate ring during cytokinesis; and then rapidly disassembles upon completion of cytokinesis. The initial recruitment of AtTAN::YFP to the division plane requires microtubules and the kinesins POK1 and POK2, but subsequent maintenance of AtTAN::YFP rings appears to be microtubule independent. Consistent with the localization data, analysis of Arabidopsis tan mutants shows that AtTAN plays a role in guidance of expanding phragmoplasts to the former PPB site.

Conclusions: AtTAN is implicated as a component of a cortical guidance cue that remains behind when the PPB is disassembled and directs the expanding phragmoplast to the former PPB site during cytokinesis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / cytology
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / analysis
  • Arabidopsis Proteins / metabolism*
  • Cell Cycle Proteins / analysis
  • Cell Cycle Proteins / metabolism*
  • Cytokinesis*
  • Kinesin / metabolism
  • Meristem / cytology
  • Meristem / metabolism
  • Microtubules / chemistry
  • Mitosis*
  • Molecular Sequence Data
  • Plants, Genetically Modified
  • Recombinant Fusion Proteins / analysis
  • Recombinant Fusion Proteins / metabolism

Substances

  • Arabidopsis Proteins
  • Cell Cycle Proteins
  • Recombinant Fusion Proteins
  • TANGLED protein, Arabidopsis
  • POK1 protein, Arabidopsis
  • POK2 protein, Arabidopsis
  • Kinesin

Associated data

  • GENBANK/DQ631804