Limits...
Myosin-Powered Membrane Compartment Drives Cytoplasmic Streaming, Cell Expansion and Plant Development.

Peremyslov VV, Cole RA, Fowler JE, Dolja VV - PLoS ONE (2015)

Bottom Line: Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics.Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming.It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering.

View Article: PubMed Central - PubMed

Affiliation: Department of Botany and Plant Pathology and Center for Genome Research and Biocomputing, Oregon State University, Corvallis, OR 97331, United States of America.

ABSTRACT
Using genetic approaches, particle image velocimetry and an inert tracer of cytoplasmic streaming, we have made a mechanistic connection between the motor proteins (myosins XI), cargo transported by these motors (distinct endomembrane compartment defined by membrane-anchored MyoB receptors) and the process of cytoplasmic streaming in plant cells. It is shown that the MyoB compartment in Nicotiana benthamiana is highly dynamic moving with the mean velocity of ~3 μm/sec. In contrast, Golgi, mitochondria, peroxisomes, carrier vesicles and a cytosol flow tracer share distinct velocity profile with mean velocities of 0.6-1.5 μm/sec. Dominant negative inhibition of the myosins XI or MyoB receptors using overexpression of the N. benthamiana myosin cargo-binding domain or MyoB myosin-binding domain, respectively, resulted in velocity reduction for not only the MyoB compartment, but also each of the tested organelles, vesicles and cytoplasmic streaming. Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics. Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming. It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering. These results support a model according to which myosin-dependent, MyoB receptor-mediated transport of a specialized membrane compartment that is conserved in all land plants drives cytoplasmic streaming that carries organelles and vesicles and facilitates cell growth and plant development.

No MeSH data available.


Related in: MedlinePlus

Model of two major particle trafficking mechanisms in plant cells.The active, myosin-driven transport of the MyoB membrane compartment along the F-actin bundles entrains cytosolic flow, which carries various organelles, vesicles and inert tracer mCherry-μNS bodies.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4591342&req=5

pone.0139331.g007: Model of two major particle trafficking mechanisms in plant cells.The active, myosin-driven transport of the MyoB membrane compartment along the F-actin bundles entrains cytosolic flow, which carries various organelles, vesicles and inert tracer mCherry-μNS bodies.

Mentions: Conspicuously, overexpression of both the myosin XI-K cargo-binding domain and the myosin-binding DUF593 domains of MyoB1 or MyoB2 resulted in the inhibition of the transport of not only the MyoB1 compartment, but also of each of the other five investigated cargoes. The extents of velocity reduction were very similar for all six cargoes, and characteristic of the particular overexpressed inhibitor, not the specific cargo (Fig 1). Because both inhibition approaches target the myosin-MyoB interactions, this outcome implies that the MyoB compartment is a major driver responsible for movements of each of the other five cargoes including the mCherry-μNS bodies (Fig 7).


Myosin-Powered Membrane Compartment Drives Cytoplasmic Streaming, Cell Expansion and Plant Development.

Peremyslov VV, Cole RA, Fowler JE, Dolja VV - PLoS ONE (2015)

Model of two major particle trafficking mechanisms in plant cells.The active, myosin-driven transport of the MyoB membrane compartment along the F-actin bundles entrains cytosolic flow, which carries various organelles, vesicles and inert tracer mCherry-μNS bodies.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591342&req=5

pone.0139331.g007: Model of two major particle trafficking mechanisms in plant cells.The active, myosin-driven transport of the MyoB membrane compartment along the F-actin bundles entrains cytosolic flow, which carries various organelles, vesicles and inert tracer mCherry-μNS bodies.
Mentions: Conspicuously, overexpression of both the myosin XI-K cargo-binding domain and the myosin-binding DUF593 domains of MyoB1 or MyoB2 resulted in the inhibition of the transport of not only the MyoB1 compartment, but also of each of the other five investigated cargoes. The extents of velocity reduction were very similar for all six cargoes, and characteristic of the particular overexpressed inhibitor, not the specific cargo (Fig 1). Because both inhibition approaches target the myosin-MyoB interactions, this outcome implies that the MyoB compartment is a major driver responsible for movements of each of the other five cargoes including the mCherry-μNS bodies (Fig 7).

Bottom Line: Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics.Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming.It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering.

View Article: PubMed Central - PubMed

Affiliation: Department of Botany and Plant Pathology and Center for Genome Research and Biocomputing, Oregon State University, Corvallis, OR 97331, United States of America.

ABSTRACT
Using genetic approaches, particle image velocimetry and an inert tracer of cytoplasmic streaming, we have made a mechanistic connection between the motor proteins (myosins XI), cargo transported by these motors (distinct endomembrane compartment defined by membrane-anchored MyoB receptors) and the process of cytoplasmic streaming in plant cells. It is shown that the MyoB compartment in Nicotiana benthamiana is highly dynamic moving with the mean velocity of ~3 μm/sec. In contrast, Golgi, mitochondria, peroxisomes, carrier vesicles and a cytosol flow tracer share distinct velocity profile with mean velocities of 0.6-1.5 μm/sec. Dominant negative inhibition of the myosins XI or MyoB receptors using overexpression of the N. benthamiana myosin cargo-binding domain or MyoB myosin-binding domain, respectively, resulted in velocity reduction for not only the MyoB compartment, but also each of the tested organelles, vesicles and cytoplasmic streaming. Furthermore, the extents of this reduction were similar for each of these compartments suggesting that MyoB compartment plays primary role in cytosol dynamics. Using gene knockout analysis in Arabidopsis thaliana, it is demonstrated that inactivation of MyoB1-4 results in reduced velocity of mitochondria implying slower cytoplasmic streaming. It is also shown that myosins XI and MyoB receptors genetically interact to contribute to cell expansion, plant growth, morphogenesis and proper onset of flowering. These results support a model according to which myosin-dependent, MyoB receptor-mediated transport of a specialized membrane compartment that is conserved in all land plants drives cytoplasmic streaming that carries organelles and vesicles and facilitates cell growth and plant development.

No MeSH data available.


Related in: MedlinePlus