Regulation of organ straightening and plant posture by an actin–myosin XI cytoskeleton

@article{Okamoto2015RegulationOO,
  title={Regulation of organ straightening and plant posture by an actin–myosin XI cytoskeleton},
  author={Keishi Okamoto and Haruko Ueda and Tomoo Shimada and Kentaro Tamura and Takehide Kato and Masao Tasaka and Miyo Terao Morita and Ikuko Hara-Nishimura},
  journal={Nature Plants},
  year={2015},
  volume={1}
}
Plants are able to bend nearly every organ in response to environmental stimuli such as gravity and light1,2. After this first phase, the responses to stimuli are restrained by an independent mechanism, or even reversed, so that the organ will stop bending and attain its desired posture. This phenomenon of organ straightening has been called autotropism3 and autostraightening4 and modelled as proprioception5. However, the machinery that drives organ straightening and where it occurs are mostly… 
How to Investigate the Role of the Actin-Myosin Cytoskeleton in Organ Straightening.
TLDR
A method for assessing the straightening ability of organs by clinostat analysis using Arabidopsis thaliana inflorescence stems of actin and myosin xi mutants as examples is described.
Functions of plant-specific myosin XI: from intracellular motility to plant postures.
Arabidopsis Myosins XI1, XI2, and XIK Are Crucial for Gravity-Induced Bending of Inflorescence Stems
TLDR
It is shown that class XI but not class VIII myosins are required for stem gravitropism of Arabidopsis, indicating a role of class XI myosin in this process.
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TLDR
The diversity entwined with plant evolution is discussed and a new model for intracellular transport regulated by multiple actin–myosin isoforms is proposed.
Myosin-driven transport network in plants is functionally robust and distinctive
TLDR
The Kurth et al. paper shows that the green branch of the tree of life has evolved a very dense and largely unique endomembrane transport network empowered by myosins XI, which is well recognized that long-range cargo transport is actin-centric in fungal and plant cells but mostly relies on microtubule-based motors in vertebrates.
Gravitropic Movement in Wheat Coleoptile is Regulated by Ultradian Growth Oscillations
TLDR
In perturbed (tilted) coleoptiles, a non-trivial coupling between the oscillatory dynamics of curvature and elongation is discovered, which appears to be critical to the postural control of the organ, and indicates the presence of a mechanism that is capable of affecting the relationship between elongation rate, differential growth, and curvature.
Actin-myosin XI: an intracellular control network in plants.
Plant Actin Cytoskeleton: New Functions from Old Scaffold
TLDR
This chapter highlights some of the recent advances toward understanding how the actin cytoskeleton modulates plant growth, form, and adaptation to the environment and discusses some recently discovered plant proteins that function in actin-mediated biological processes that are unique to plants.
Nutations in Plant Shoots: Endogenous and Exogenous Factors in the Presence of Mechanical Deformations
TLDR
It is shown that, in the absence of endogenous cues, pendular and circular oscillations arise as a critical length is attained, thus suggesting the occurrence of a Hopf bifurcation reminiscent of flutter instabilities exhibited by structural systems under nonconservative loads.
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