Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2015 Apr;8(4):582-94.
doi: 10.1016/j.molp.2014.12.023. Epub 2015 Jan 9.

Focusing on the focus: what else beyond the master switches for polar cell growth?

Yuan Qin  1 , Juan Dong  2
Affiliations
Review

Focusing on the focus: what else beyond the master switches for polar cell growth?

Yuan Qin et al. Mol Plant. 2015 Apr.

Abstract

Cell polarity, often associated with polarized cell expansion/growth in plants, describes the uneven distribution of cellular components, such as proteins, nucleic acids, signaling molecules, vesicles, cytoskeletal elements, and organelles, which may ultimately modulate cell shape, structure, and function. Pollen tubes and root hairs are model cell systems for studying the molecular mechanisms underlying sustained tip growth. The formation of intercalated epidermal pavement cells requires excitatory and inhibitory pathways to coordinate cell expansion within single cells and between cells in contact. Strictly controlled cell expansion is linked to asymmetric cell division in zygotes and stomatal lineages, which require integrated processes of pre-mitotic cellular polarization and division asymmetry. While small GTPase ROPs are recognized as fundamental signaling switches for cell polarity in various cellular and developmental processes in plants, the broader molecular machinery underpinning polarity establishment required for asymmetric division remains largely unknown. Here, we review the widely used ROP signaling pathways in cell polar growth and the recently discovered feedback loops with auxin signaling and PIN effluxers. We discuss the conserved phosphorylation and phospholipid signaling mechanisms for regulating uneven distribution of proteins, as well as the potential roles of novel proteins and MAPKs in the polarity establishment related to asymmetric cell division in plants.

Keywords: cell expansion; cytoskeleton; polarity; polarity determination; signal transduction.

PubMed Disclaimer

Figures

Figure 1
Figure 1
An integrated model for tip growth of pollen tubes. (a) A diagram demonstrates the intracellular organization of a growing pollen tube. (b) Upper panel: a self-organizing ROP1 signaling network controls the oscillation of pollen tube tip growth. Bottom panel: the apical ROP1 activity oscillates ahead of tip growth, followed by the Ca2+ gradient oscillates.
Figure 2
Figure 2
The ROP small GTPases-based molecular mechanism for coordinated cell polar growth to form puzzle-shaped pavement cells. (a) Schematic representation of the cytoskeletal architecture in intercalary pavement cells. (b) A simplified model for the auxin-controlled interdigitation through antagonistic ROP2 and ROP6 pathways that direct the formation of lobes and indentations, respectively.
Figure 3
Figure 3
Zygote and stomatal lineage system: cell polarity formation and asymmetric cell division (ACD). (a) Schematic depiction of zygote ACD (left) and the hypothesized genetic mechanisms in polarity formation (right). (b–c) Schematic depiction of stomatal ACD in Arabidopsis (b) and maize (c). Thick dashed lines in (b–c) indicate where the polarity complexes, BASL/POLAR and PANs/ROPs, are localized. CV, central vacuole. N, nucleus. SMC, subsidiary mother cell. SC, subsidiary cell. GMC, guard mother cell. GCs, guard cells.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Anthony RG, Henriques R, Helfer A, Meszaros T, Rios G, Testerink C, Munnik T, Deak M, Koncz C, Bogre L. A protein kinase target of a PDK1 signalling pathway is involved in root hair growth in Arabidopsis. The EMBO journal. 2004;23:572–581. - PMC - PubMed
    1. Baskin TI. On the alignment of cellulose microfibrils by cortical microtubules: a review and a model. Protoplasma. 2001;215:150–171. - PubMed
    1. Basu D, Le J, Zakharova T, Mallery EL, Szymanski DB. A SPIKE1 signaling complex controls actin-dependent cell morphogenesis through the heteromeric WAVE and ARP2/3 complexes. Proceedings of the National Academy of Sciences of the United States of America. 2008;105:4044–4049. - PMC - PubMed
    1. Bayer M, Nawy T, Giglione C, Galli M, Meinnel T, Lukowitz W. Paternal control of embryonic patterning in Arabidopsis thaliana. Science. 2009;323:1485–1488. - PubMed
    1. Beck M, Komis G, Ziemann A, Menzel D, Samaj J. Mitogen-activated protein kinase 4 is involved in the regulation of mitotic and cytokinetic microtubule transitions in Arabidopsis thaliana. The New phytologist. 2011;189:1069–1083. - PubMed

Publication types

MeSH terms

LinkOut - more resources