Abstract
The molecular mechanisms that control organ shape during flower development are largely unknown. By using differential hybridization techniques, a cDNA designated GEG (for Gerbera hybrida homolog of the gibberellin [GA]-stimulated transcript 1 [GAST1] from tomato) was isolated from a library representing late stages of corolla development in Gerbera. GEG expression was detected in corollas and carpels, with expression spatiotemporally coinciding with flower opening. In corollas and styles, GEG expression is temporally correlated with the cessation of longitudinal cell expansion. In plants constitutively expressing GEG, reduced corolla lengths and carpels with shortened and radially expanded stylar parts were found, with concomitant reduction of longitudinal cell expansion in these organs. In addition, in styles, an increase in radial cell expansion was detected. Taken together, these observations indicate a regulatory role for the GEG gene product in determining the shape of the corolla and carpel. The deduced amino acid sequence of the GEG gene product shares high similarity with previously characterized putative cell wall proteins encoded by GA-inducible genes, namely, GAST1, GIP (for GA-induced gene of petunia), and the GASA (for GA-stimulated in Arabidopsis) gene family. Our studies suggest that GEG, the expression of which can also be induced by application of GA3, plays a role in phytohormone-mediated cell expansion.
Full Text
The Full Text of this article is available as a PDF (829.5 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aeschbacher R. A., Hauser M. T., Feldmann K. A., Benfey P. N. The SABRE gene is required for normal cell expansion in Arabidopsis. Genes Dev. 1995 Feb 1;9(3):330–340. doi: 10.1101/gad.9.3.330. [DOI] [PubMed] [Google Scholar]
- Aubert D., Chevillard M., Dorne A. M., Arlaud G., Herzog M. Expression patterns of GASA genes in Arabidopsis thaliana: the GASA4 gene is up-regulated by gibberellins in meristematic regions. Plant Mol Biol. 1998 Apr;36(6):871–883. doi: 10.1023/a:1005938624418. [DOI] [PubMed] [Google Scholar]
- Ben-Nissan G., Weiss D. The petunia homologue of tomato gast1: transcript accumulation coincides with gibberellin-induced corolla cell elongation. Plant Mol Biol. 1996 Dec;32(6):1067–1074. doi: 10.1007/BF00041390. [DOI] [PubMed] [Google Scholar]
- Coen E. S., Carpenter R., Martin C. Transposable elements generate novel spatial patterns of gene expression in Antirrhinum majus. Cell. 1986 Oct 24;47(2):285–296. doi: 10.1016/0092-8674(86)90451-4. [DOI] [PubMed] [Google Scholar]
- Coen E. S., Meyerowitz E. M. The war of the whorls: genetic interactions controlling flower development. Nature. 1991 Sep 5;353(6339):31–37. doi: 10.1038/353031a0. [DOI] [PubMed] [Google Scholar]
- Elomaa P., Mehto M., Kotilainen M., Helariutta Y., Nevalainen L., Teeri T. H. A bHLH transcription factor mediates organ, region and flower type specific signals on dihydroflavonol-4-reductase (dfr) gene expression in the inflorescence of Gerbera hybrida (Asteraceae). Plant J. 1998 Oct;16(1):93–99. doi: 10.1046/j.1365-313x.1998.00273.x. [DOI] [PubMed] [Google Scholar]
- Hauser M. T., Morikami A., Benfey P. N. Conditional root expansion mutants of Arabidopsis. Development. 1995 Apr;121(4):1237–1252. doi: 10.1242/dev.121.4.1237. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Helariutta Y., Elomaa P., Kotilainen M., Seppänen P., Teeri T. H. Cloning of cDNA coding for dihydroflavonol-4-reductase (DFR) and characterization of dfr expression in the corollas of Gerbera hybrida var. Regina (Compositae). Plant Mol Biol. 1993 May;22(2):183–193. doi: 10.1007/BF00014927. [DOI] [PubMed] [Google Scholar]
- Herzog M., Dorne A. M., Grellet F. GASA, a gibberellin-regulated gene family from Arabidopsis thaliana related to the tomato GAST1 gene. Plant Mol Biol. 1995 Feb;27(4):743–752. doi: 10.1007/BF00020227. [DOI] [PubMed] [Google Scholar]
- Huang N., Sutliff T. D., Litts J. C., Rodriguez R. L. Classification and characterization of the rice alpha-amylase multigene family. Plant Mol Biol. 1990 May;14(5):655–668. doi: 10.1007/BF00016499. [DOI] [PubMed] [Google Scholar]
- Jones J. D., Dunsmuir P., Bedbrook J. High level expression of introduced chimaeric genes in regenerated transformed plants. EMBO J. 1985 Oct;4(10):2411–2418. doi: 10.1002/j.1460-2075.1985.tb03949.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kotilainen M., Helariutta Y., Elomaa P., Paulin L., Teeri T. H. A corolla- and carpel-abundant, non-specific lipid transfer protein gene is expressed in the epidermis and parenchyma of Gerbera hybrida var. Regina (Compositae). Plant Mol Biol. 1994 Nov;26(3):971–978. doi: 10.1007/BF00028863. [DOI] [PubMed] [Google Scholar]
- Martin C., Gerats T. Control of Pigment Biosynthesis Genes during Petal Development. Plant Cell. 1993 Oct;5(10):1253–1264. doi: 10.1105/tpc.5.10.1253. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meyerowitz E. M. Genetic control of cell division patterns in developing plants. Cell. 1997 Feb 7;88(3):299–308. doi: 10.1016/s0092-8674(00)81868-1. [DOI] [PubMed] [Google Scholar]
- Sablowski R. W., Meyerowitz E. M. A homolog of NO APICAL MERISTEM is an immediate target of the floral homeotic genes APETALA3/PISTILLATA. Cell. 1998 Jan 9;92(1):93–103. doi: 10.1016/s0092-8674(00)80902-2. [DOI] [PubMed] [Google Scholar]
- Shi L., Gast R. T., Gopalraj M., Olszewski N. E. Characterization of a shoot-specific, GA3- and ABA-regulated gene from tomato. Plant J. 1992 Mar;2(2):153–159. [PubMed] [Google Scholar]
- Skriver K., Olsen F. L., Rogers J. C., Mundy J. cis-acting DNA elements responsive to gibberellin and its antagonist abscisic acid. Proc Natl Acad Sci U S A. 1991 Aug 15;88(16):7266–7270. doi: 10.1073/pnas.88.16.7266. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Taylor B. H., Scheuring C. F. A molecular marker for lateral root initiation: the RSI-1 gene of tomato (Lycopersicon esculentum Mill) is activated in early lateral root primordia. Mol Gen Genet. 1994 Apr;243(2):148–157. doi: 10.1007/BF00280311. [DOI] [PubMed] [Google Scholar]
- Tsuge T., Tsukaya H., Uchimiya H. Two independent and polarized processes of cell elongation regulate leaf blade expansion in Arabidopsis thaliana (L.) Heynh. Development. 1996 May;122(5):1589–1600. doi: 10.1242/dev.122.5.1589. [DOI] [PubMed] [Google Scholar]
- von Heijne G. A new method for predicting signal sequence cleavage sites. Nucleic Acids Res. 1986 Jun 11;14(11):4683–4690. doi: 10.1093/nar/14.11.4683. [DOI] [PMC free article] [PubMed] [Google Scholar]