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Hypocotyl transcriptome reveals auxin regulation of growth-promoting genes through GA-dependent and -independent pathways.

ABSTRACT: Many processes critical to plant growth and development are regulated by the hormone auxin. Auxin responses are initiated through activation of a transcriptional response mediated by the TIR1/AFB family of F-box protein auxin receptors as well as the AUX/IAA and ARF families of transcriptional regulators. However, there is little information on how auxin regulates a specific cellular response. To begin to address this question, we have focused on auxin regulation of cell expansion in the Arabidopsis hypocotyl. We show that auxin-mediated hypocotyl elongation is dependent upon the TIR1/AFB family of auxin receptors and degradation of AUX/IAA repressors. We also use microarray studies of elongating hypocotyls to show that a number of growth-associated processes are activated by auxin including gibberellin biosynthesis, cell wall reorganization and biogenesis, and others. Our studies indicate that GA biosynthesis is required for normal response to auxin in the hypocotyl but that the overall transcriptional auxin output consists of PIF-dependent and -independent genes. We propose that auxin acts independently from and interdependently with PIF and GA pathways to regulate expression of growth-associated genes in cell expansion.

SUBMITTER: Chapman EJ

PROVIDER: S-EPMC3348943 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Hypocotyl transcriptome reveals auxin regulation of growth-promoting genes through GA-dependent and -independent pathways.

Chapman Elisabeth J EJ Greenham Kathleen K Castillejo Cristina C Sartor Ryan R Bialy Agniezska A Sun Tai-Ping TP Estelle Mark M

PloS one 20120509 5

Many processes critical to plant growth and development are regulated by the hormone auxin. Auxin responses are initiated through activation of a transcriptional response mediated by the TIR1/AFB family of F-box protein auxin receptors as well as the AUX/IAA and ARF families of transcriptional regulators. However, there is little information on how auxin regulates a specific cellular response. To begin to address this question, we have focused on auxin regulation of cell expansion in the Arabido ...[more]

PMID: 22590525

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Hypocotyl transcriptome reveals auxin regulation of growth-promoting genes through GA-dependent and -independent pathways.

Publications

Hypocotyl transcriptome reveals auxin regulation of growth-promoting genes through GA-dependent and -independent pathways.

Similar Datasets

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