Gibberellin and abscisic acid regulate GAST1 expression at the level of transcription

Lifang Shi, Neil E. Olszewski

Research output: Contribution to journalArticle

36 Scopus citations

Abstract

Both gibberellic acid (GA3) and abscisic acid (ABA) regulate the expression of the GAST1 gene of tomato. Treatment with GA3 increases the abundance of GAST1 RNA while treatment with ABA blocks this effect. In this study, the effects of GA3 and ABA on the rate of transcription of the GAST1 gene and the stability of GAST1 RNA were examined. Nuclear run-on analyses detected an increase in transcription of the GAST1 gene 1 h after GA3 treatment with transcription increasing to a maximum at 9 h after treatment. The half-life of GAST1 RNA in GA3-treated leaves was similar to that in control leaves. In addition, the extent of overexpression of GAST1 RNA in transgenic tomato plants containing the CaMV 35S promoter driving the expression of the GAST1 transcribed region was largely unaffected by GA3. These results suggest that GA3 stimulates the expression of the GAST1 gene by acting only at the level of transcription. ABA treatment dramatically reduced the abundance of GAST1 RNA in gib1 shoots through an effect at the level of transcription and did not appear to affect the stability of this RNA. Midcourse ABA addition to the GA3-incubated shoots reversed the GA3-mediated increase in the transcription of GAST1 gene within 15 min. Transgenic plants that either overexpressed or underexpressed GAST1 RNA exhibited no phenotypic differences from wild type.

Original languageEnglish (US)
Pages (from-to)1053-1060
Number of pages8
JournalPlant molecular biology
Volume38
Issue number6
DOIs
StatePublished - Dec 1 1998

Keywords

  • Abscisic acid (ABA)
  • Gene transcription
  • Gibberellin (GA)
  • Nuclear run-on
  • RNA stability

Fingerprint Dive into the research topics of 'Gibberellin and abscisic acid regulate GAST1 expression at the level of transcription'. Together they form a unique fingerprint.

  • Cite this