The plant microtubule-associated protein AtMAP65-3/PLE is essential for cytokinetic phragmoplast function.
Directional cell expansion in interphase and nuclear and cell division in M-phase are mediated by four microtubule arrays, three of which are unique to plants: the interphase array, the preprophase band, and the phragmoplast. The plant microtubule-associated protein MAP65 has been identified as a key structural component in these arrays. The Arabidopsis genome has nine MAP65 genes, and here we show that one, AtMAP65-3/PLE, locates only to the mitotic arrays and is essential for cytokinesis. The Arabidopsis pleiade (ple) alleles are single recessive mutations, and we show that these mutations are in the AtMAP65-3 gene. Moreover, these mutations cause C-terminal truncations that abolish microtubule binding. In the ple mutants the anaphase spindle is normal, and the cytokinetic phragmoplast can form but is distorted; not only is it wider, but the midline, the region where oppositely oriented microtubules overlap, is unusually expanded. Here we present data that demonstrate an essential role for AtMAP65-3/PLE in cytokinesis in plant cells.
Müller
Sabine
S
The Institute of Applied Genetics, BOKU-University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
Smertenko
Andrei
A
Wagner
Vera
V
Heinrich
Maria
M
Hussey
Patrick J
PJ
Hauser
Marie-Theres
MT
D000483:Alleles; D017360:Arabidopsis; D002455:Cell Division / Q000502:physiology; D002498:Centrifugation; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D049452:Green Fluorescent Proteins; D007150:Immunohistochemistry; D008164:Luminescent Proteins / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000235:genetics* / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism / Q000502:physiology*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins; D017422:Sequence Analysis, DNA; D008941:Spindle Apparatus / Q000378:metabolism / Q000502:physiology*
D017931:DNA Primers; D018076:DNA, Complementary; D008164:Luminescent Proteins; D008869:Microtubule-Associated Proteins; D010940:Plant Proteins; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins