Root gravitropism: a complex response to a simple stimulus?

Rosen, E.; Chen, R.; Masson, P. H.

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NASA NTRS · 20040141819

Root gravitropism: a complex response to a simple stimulus?

Rosen, E.·Chen, R.·Masson, P. H.

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Abstract

Roots avoid depleting their immediate environment of essential nutrients by continuous growth. Root growth is directed by environmental cues, including gravity. Gravity sensing occurs mainly in the columella cells of the root cap. Upon reorientation within the gravity field, the root-cap amyloplasts sediment, generating a physiological signal that promotes the development of a curvature at the root elongation zones. Recent molecular genetic studies in Arabidopsis have allowed the identification of genes that play important roles in root gravitropism. Among them, the ARG1 gene encodes a DnaJ-like protein involved in gravity signal transduction, whereas the AUX1 and AGR1 genes encode proteins involved in polar auxin transport. These studies have important implications for understanding the intra- and inter-cellular signaling processes that underlie root gravitropism.

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Review, Tutorial NASA Discipline Plant Biology Non-NASA Center Review Auxins/metabolism/physiology Arabidopsis Proteins Gravitropism/genetics/physiology Signal Transduction/genetics/physiology Genes, Plant Plant Roots/genetics/growth & development/metabolism Arabidopsis Gravity Perception/physiology Heat-Shock Proteins Plastids/physiology Plant Proteins Support, U.S. Gov't, Non-P.H.S Carrier Proteins

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Rosen, E., Chen, R., Masson, P. H.. 1999-10-01. Root gravitropism: a complex response to a simple stimulus?. https://ntrs.nasa.gov/citations/20040141819

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