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New Insights in Plant Biology Gained from Research in Space Cover

New Insights in Plant Biology Gained from Research in Space

Gravitational and Space Research
Volume 3 (2015): Issue 2 (December 2015)
By: Ashley E. Cannon,  Mari L. Salmi,  Gregory Clark and  Stanley Roux  
Open Access
|Dec 2015

Figures & Tables

Figure 1.

Early growth and developmental time-line of Ceratopteris richardii spores. Spore germination is initiated by water and red light. Within hours of initiation, calcium enters through channels at the bottom of spores and there is an efflux of calcium out of the top. The calcium efflux peaks between 7 and 12 hours after light-initiated germination begins. Polarity of development is set by gravity after 24-30 hours of growth and it results in the downward migration of the cell nucleus and a subsequent asymmetrical cell division. A visual representation of the direction of polarity set by gravity is the emergence of a downward-growing rhizoid 72 hours after germination begins.
Early growth and developmental time-line of Ceratopteris richardii spores. Spore germination is initiated by water and red light. Within hours of initiation, calcium enters through channels at the bottom of spores and there is an efflux of calcium out of the top. The calcium efflux peaks between 7 and 12 hours after light-initiated germination begins. Polarity of development is set by gravity after 24-30 hours of growth and it results in the downward migration of the cell nucleus and a subsequent asymmetrical cell division. A visual representation of the direction of polarity set by gravity is the emergence of a downward-growing rhizoid 72 hours after germination begins.

Figure 2.

Hypothetical model showing the role of eATP and calcium in polarization of Ceratopteris richardii spores. In response to gravity, an undefined mass would settle, selectively activating mechano-sensitive channels primarily along the bottom of the spore. These mechano-sensitive channels could release ATP. The ATP released accumulates asymmetrically, resulting in a gradient where the eATP on the bottom of the spore is higher than the top. The eATP could activate calcium channels directly or indirectly, establishing or contributing to the initiation of the trans-cell Ca2+ current that is essential for gravity-directed polarization.
Hypothetical model showing the role of eATP and calcium in polarization of Ceratopteris richardii spores. In response to gravity, an undefined mass would settle, selectively activating mechano-sensitive channels primarily along the bottom of the spore. These mechano-sensitive channels could release ATP. The ATP released accumulates asymmetrically, resulting in a gradient where the eATP on the bottom of the spore is higher than the top. The eATP could activate calcium channels directly or indirectly, establishing or contributing to the initiation of the trans-cell Ca2+ current that is essential for gravity-directed polarization.
DOI: https://doi.org/10.2478/gsr-2015-0007 | Journal eISSN: 2332-7774
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Language: English
Page range: 3 - 19
Published on: Dec 1, 2015
Published by: American Society for Gravitational and Space Research
In partnership with: Paradigm Publishing Services
Publication frequency: 2 issues per year
Keywords:
Plant Space Research,
Gravitropism,
Polarization,
Plant Biology,
Arabidopsis,
Ceratopteris,
Gravity Perception
Related subjects:
Life sciences,
Life sciences, other,
Materials sciences,
Materials sciences, other,
Physics,
Physics, other

© 2015 Ashley E. Cannon, Mari L. Salmi, Gregory Clark, Stanley Roux, published by American Society for Gravitational and Space Research
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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