Root development: signaling down and around.

J W Wysocka-Diller; P N Benfey

doi:10.1002/bies.950191105

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Root development: signaling down and around.

J W Wysocka-Diller·P N Benfey

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Abstract

Because of its elegant simplicity, the Arabidopsis root has become a model for studying plant organogenesis. In this review we focus on recent results indicating the importance of signaling in root development. A role for positional information in root cell specification has been demonstrated by ablation analyses. Through mutational analysis, genes have been identified that play a role in radial pattern formation. The embryonic phenotypes of these mutants raised the possibility that division patterns in post-embryonic roots are dependent on signaling that originates during embryonic development. Analysis of expression of the SCARECROW gene indicates that it may play a role in this 'top-down' signaling process. Characterization of root epidermis development has led to the identification of negative regulators of root-hair formation. These appear to set up a prepattern which is reinforced by signaling by plant hormones.

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Arabidopsis Arabidopsis Proteins Cell Differentiation Gene Expression Regulation, Plant Models, Biological Mutation Plant Proteins Plant Roots Signal Transduction Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.Review

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J W Wysocka-Diller, P N Benfey. 1997. Root development: signaling down and around.. https://doi.org/10.1002/bies.950191105

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