Abstract
Bioactive gibberellin (GA) regulates the growth and development of a wide array of plant species. GA exerts its effects via members of the DELLA protein family of putative transcriptional regulators. The GAI gene encodes GAI, a DELLA protein from Arabidopsis thaliana (L.) Heyhn. A mutant allele, gai, encodes a mutant protein (gai) that has altered properties, and confers a dominant, reduced GA-response, dwarf phenotype. Here we describe experiments to investigate the effects of transgenic expression of GAI and gai in tobacco. Constructs permitting the expression of the GAI and gai open reading frames (ORFs) at higher (driven by the cauliflower mosaic virus 35S promoter) and lower (driven by the original Arabidopsis GAI promoter) levels in tobacco were made. We show that low-level expression of GAI has no detectable effect on tobacco GA-responses. In contrast, high-level expression of GAI clearly affects the growth of adult tobacco plants and the GA-responsiveness of tobacco hypocotyls. Both low- and high-level expression of gai have effects on tobacco GA responses. Thus, tobacco GA-responses are affected by transgenic expression of GAI/gai, and the degree to which these responses are affected is related to the level of transgene expression.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Boss PK and Thomas MR (2002) Association of dwarfism and floral induction with a grape 'green revolution' mutation. Nature 416: 847–850.
Chandler PM, Marion-Poll A, Ellis M and Gubler F (2002) Mutants at the Slender1 locus of barley cv. Himalaya. Molecular and physiological characterization. Plant Physiol 129: 181–190.
Chomczynski P (1993) A reagent for the single-step isolation of RNA, DNA and proteins from cell and tissue samples. Biotechniques 15: 532–537.
Church GM and Gilbert W (1984) Genomic sequencing. Proc Natl Acad Sci USA 81: 1991–1995.
Cowling RJ and Harberd NP (1999) Gibberellins control Arabidopsis hypocotyl growth via regulation of cellular elongation. J Exp Bot 50: 1351–1357.
Cowling RJ, Kamiya Y, Seto H and Harberd NP (1998) Gibberellin dose-response regulation of GA4 gene transcript levels in Arabidopsis. Plant Physiol 117: 1195–1203.
Dill A and Sun T-p (2001) Synergistic derepression of gibberellin signaling by removing RGA and GAI function in Arabidopsis thaliana. Genetics 159: 777–785.
Dill A, Jung H-S and Sun T-p (2001) The DELLA motif is essential for gibberellin-induced degradation of RGA. Proc Natl Acad Sci USA 98: 14162–14167.
Feinberg AP and Volgestein B (1983) A technique for radiolabelling DNA restriction endonuclease fragments to high specific activity. Anal Biochem 132: 6–13.
Fleck B and Harberd NP (2002) Evidence that the Arabidopsis nuclear gibberellin signalling protein GAI is not destabilised by gibberellin. Plant J 32: 935–947.
Fu X, Sudhakar D, Peng J, Richards DE, Christou P and Harberd NP (2001) Expression of Arabidopsis GAI in transgenic rice represses multiple gibberellin responses. The Plant Cell 13: 1791–1802.
Gubler F, Chandler PM, White RG, Llewellyn DJ and Jacobsen JV (2002) Gibberellin signaling in barley aleurone cells. Control of SLN1 and GAMYB expression. Plant Physiol 129: 191–200.
Guerineau F and Mullineaux P (1993) Plant transformation and expression vectors. In: Croy RR (ed.), Plant Molecular Biology LABFAX. (pp. 121–147) Bios Scientific Publishers, Oxford.
Harberd NP, King KE, Carol P, Cowling RJ, Peng J and Richards DE (1998) Gibberellin: inhibitor of an inhibitor of...? BioEssays 20: 1001–1008.
Hooley R (1994) Gibberellins: perception, transduction and responses. Plant Mol Biol 26: 1529–1555.
Horsch RB, Fry JE, Hoffman NL, Eichholtz D, Rogers SG and Fraley RT (1985) A simple method of transferring genes into plants. Science 227: 1229–1231.
Ikeda A, Ueguchi-Tanaka M, Sonoda Y, Kitano H, Koshioka M, Futsuhara Y et al. (2001) Slender rice, a constitutive gibberellin response mutant, is caused by a null mutation of the SLR1 gene, an ortholog of the height-regulating gene GAI/RGA/RHT/D8. The Plant Cell 13: 999–1010.
Itoh H, Ueguchi-Tanaka M, Sato Y, Ashikari M and Matsuoka M (2002) The gibberellin signaling pathway is regulated by the appearance and disappearance of SLENDER RICE1 in nuclei. The Plant Cell 14: 1–16.
Jones JDG, Shlumukov L, Carland F, English J, Scofield SR, Bishop GJ et al. (1992) Effective vectors for transformation, expression of heterologous genes, and assaying transposon excision in transgenic plants. Transgenic Res 1: 285–297.
King KE, Moritz T and Harberd NP (2001) Gibberellins are not required for stem growth in Arabidopsis thaliana in the absence of GAI and RGA. Genetics 159: 767–776.
Koornneef M and van der Veen JH (1980) Induction and analysis of gibberellin sensitive mutants in Arabidopsis thaliana (L.) Hehyn. Theor Appl Genet 58: 257–263.
Koornneef M, Elgersma A, Hanhart CJ, van Loenen-Martinet EP, van Rign L and Zeevaart JAD (1985) A gibberellin insensitive mutant of Arabidopsis thaliana. Physiol Plant 65: 33–39.
Lee S, Cheng H, King KE, Wang W, He Y, Hussain A (2002) Gibberellin regulates Arabidopsis seed germination via RGL2, a GAI/RGA-like gene whose expression is up-regulated following imbibition. Genes Dev 16: 646–658.
Peng J and Harberd NP (1993) Derivative alleles of the Arabidopsis gibberellin-insensitive (gai) mutation confer a wild-type phenotype. The Plant Cell 5: 351–360.
Peng J, Carol P, Richards DE, King KE, Cowling RJ, Murphy GP et al. (1997) The Arabidopsis GAI gene defines a signaling pathway that negatively regulates gibberellin responses. Genes Dev 11: 3194–3205.
Peng J, Richards DE, Moritz T, Caño-Delgado A and Harberd NP (1999a) Extragenic suppressors of the Arabidopsis gai mutation alter the dose-response relationship of diverse gibberellin responses. Plant Physiol 119: 1199–1207.
Peng J, Richards DE, Hartley NM, Murphy GP, Devos KM, Flintham JE et al. (1999b) 'Green Revolution' genes encode mutant gibberellin response modulators. Nature 400: 256–261.
Peng J, Richards DE, Moritz T, Ezura H, Carol P and Harberd NP (2002) Molecular and physiological characterization of Arabidopsis GAI alleles obtained in targeted Ds-tagging experiments. Planta 214: 591–596.
Pysh LD, Wysocka-Diller JW, Camilleri C, Bouchez D and Benfey PN (1999) The GRAS gene family in Arabidopsis: sequence characterization and basic expression analysis of the SCARECROW-LIKE genes. Plant J 18: 111–119.
Richards D E, King KE, Ait-ali T and Harberd NP (2001) How gibberellin regulates plant growth and development: a molecular genetic analysis of gibberellin signaling. Ann Rev Plant Physiol Plant Mol Biol 52: 67–88.
Silverstone AL, Jung HS, Dill A et al. (2001) Repressing a repressor: gibberellin-induced rapid reduction of the RGA protein in Arabidopsis. Plant Cell 13: 1555–1565.
Talon M, Koornneef M and Zeevaart JAD (1990) Accumulation of C19-gibberellins in the gibberellin-insensitive dwarf mutant gai of Arabidopsis thaliana (L.) Heynh. Planta 182: 501–505.
Wen C-K and Chang C (2002) Arabidopsis RGL1 encodes a negative regulator of gibberellin responses. The Plant Cell 14: 87–100.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Hynes, L.W., Peng, J., Richards, D.E. et al. Transgenic Expression of the Arabidopsis DELLA Proteins GAI and gai Confers Altered Gibberellin Response in Tobacco. Transgenic Res 12, 707–714 (2003). https://doi.org/10.1023/B:TRAG.0000005145.68017.6e
Issue Date:
DOI: https://doi.org/10.1023/B:TRAG.0000005145.68017.6e