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NASA NTRS · 20040090239

Plastids: dynamic components of plant cell development

Guikema, J. A.·Gallegos, G. L.·Spooner, B. S.
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Abstract

The gravitropic bending of maize roots, as a response to reorientation of the root within a gravitational field, was examined for sensitivity to exogenous applications of the cytoskeletal inhibitor, cytochalasin D. Agar blocks were impregnated with this inhibitor, and were applied either to the root cap or to the zone of root cell elongation. Root growth was normal with either treatment, if the roots were not repositioned with respect to the gravitational vector. When untreated roots were placed in a horizontal position with respect to gravity, a 40 degree bending response was observed within one hour. This bending also occurred when cytochalasin D was applied at high concentrations to the zone of root cell elongation. However, when cytochalasin D above 40 micrograms/ml was applied to the root cap, roots lost the ability of directional reorientation within the gravitational field, causing a random bending.

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NASA Discipline Cell BiologyNASA Discipline Developmental BiologyNASA Discipline Number 93-10NASA Program NSCORTNon-NASA CenterGravitropism/drug effects/physiologyCytochalasin D/pharmacologyZea mays/cytology/drug effects/physiologyPlant Roots/cytology/drug effects/physiologyCytoskeleton/drug effects/physiologyPlastids/drug effects/physiologySupport, U.S. Gov't, Non-P.H.SSupport, U.S. Gov't, P.H.SPlant Root Cap/cytology/drug effects/physiology

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Guikema, J. A., Gallegos, G. L., Spooner, B. S.. 1992-01-01. Plastids: dynamic components of plant cell development. https://ntrs.nasa.gov/citations/20040090239

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