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

Published

Journal Article

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.

Full Text

Duke Authors

Cited Authors

  • Chapman, EJ; Greenham, K; Castillejo, C; Sartor, R; Bialy, A; Sun, T-P; Estelle, M

Published Date

  • January 2012

Published In

Volume / Issue

  • 7 / 5

Start / End Page

  • e36210 -

PubMed ID

  • 22590525

Pubmed Central ID

  • 22590525

Electronic International Standard Serial Number (EISSN)

  • 1932-6203

International Standard Serial Number (ISSN)

  • 1932-6203

Digital Object Identifier (DOI)

  • 10.1371/journal.pone.0036210

Language

  • eng