Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

The NPH4 Locus Encodes the Auxin Response Factor ARF7, a Conditional Regulator of Differential Growth in Aerial Arabidopsis Tissue

Reneé M. Harper, Emily L. Stowe-Evans, Darron R. Luesse, Hideki Muto, Kiyoshi Tatematsu, Masaaki K. Watahiki, Kotaro Yamamoto and Emmanuel Liscum
The Plant Cell
Vol. 12, No. 5 (May, 2000), pp. 757-770
DOI: 10.2307/3870999
Stable URL: http://www.jstor.org/stable/3870999
Page Count: 14
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
The NPH4 Locus Encodes the Auxin Response Factor ARF7, a Conditional Regulator of Differential Growth in Aerial Arabidopsis Tissue
Preview not available

Abstract

Organ bending through differential growth represents a major mechanism by which plants are able to adaptively alter their morphology in response to local changes in the environment. Two plant hormones, auxin and ethylene, have been implicated as regulators of differential growth responses; however, the mechanisms by which they elicit their effects remain largely unknown. Here, we describe isolation of the NPH4 gene of Arabidopsis, which is conditionally required for differential growth responses of aerial tissues, and we report that NPH4 encodes the auxin-regulated transcriptional activator ARF7. The phenotypes of nph4 mutants, which include multiple differential growth defects associated with reduced auxin responsiveness, including impaired auxin-induced gene expression, are consistent with the predicted loff of function of a transcriptional activator, and these phenotypes indicate that auxin-dependent changes in gene transcription are prerequisite for proper organ bending responses. Although NPH4/ARF7 appears to be a major regulator of differential growth, it is not the sole regulator because phenotypes of nph4 null mutants were suppressed by application of ethylene. This latter finding illustrates the intimate connection between auxin and ethylene in the control of growth in higher plants.

Page Thumbnails

  • Thumbnail: Page 
[757]
    [757]
  • Thumbnail: Page 
758
    758
  • Thumbnail: Page 
759
    759
  • Thumbnail: Page 
760
    760
  • Thumbnail: Page 
761
    761
  • Thumbnail: Page 
762
    762
  • Thumbnail: Page 
763
    763
  • Thumbnail: Page 
764
    764
  • Thumbnail: Page 
765
    765
  • Thumbnail: Page 
766
    766
  • Thumbnail: Page 
767
    767
  • Thumbnail: Page 
768
    768
  • Thumbnail: Page 
769
    769
  • Thumbnail: Page 
770
    770