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Title: Microtubule nucleation for the assembly of acentrosomal microtubule arrays in plant cells
Summary

Cytoskeletal microtubules (MTs) have a multitude of functions including intracellular distribution of molecules and organelles, cell morphogenesis, as well as segregation of the genetic material and separation of the cytoplasm during cell division among eukaryotic organisms. In response to internal and external cues, eukaryotic cells remodel theirMTnetwork in a regulated manner in order to assemble physiologically important arrays for cell growth, cell proliferation, or for cells to cope with biotic or abiotic stresses. Nucleation of newMTs is a critical step forMTremodeling. Although many key factors contributing toMTnucleation and organization are well conserved in different kingdoms, the centrosome, representing the most prominent microtubule organizing centers (MTOCs), disappeared during plant evolution as angiosperms lack the structure. Instead, flexibleMTOCs may emerge on the plasma membrane, the nuclear envelope, and even organelles depending on types of cells and organisms and/or physiological conditions.MT‐dependentMTnucleation is particularly noticeable in plant cells because it accounts for the primary source ofMTgeneration for assembling spindle, phragmoplast, and cortical arrays when the γ‐tubulin ring complex is anchored and activated by the augmin complex. It is intriguing what proteins are associated with plant‐specificMTOCs and how plant cells activate or inactivateMTnucleation activities in spatiotemporally regulated manners.

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NSF-PAR ID:
10460950
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
222
Issue:
4
ISSN:
0028-646X
Format(s):
Medium: X Size: p. 1705-1718
Size(s):
["p. 1705-1718"]
Sponsoring Org:
National Science Foundation
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