Abstract
Expression and physiological effects of the root-inducing rolB gene of Agrobacterium rhizogenes T-DNA were studied simultaneously in tobacco (Nicotiana tabacum) mesophyll protoplasts. The kinetic study of the expression of rolB mRNA following exogenous auxin application showed that auxin transiently stimulated rolB expression, with mRNA levels starting to accumulate 6 to 9 h after auxin was supplied and increasing 300-fold after 12 to 18 h. The parallel study of the auxin sensitivity of rolB-transformed protoplasts, as assayed by their electrical response to the hormone, showed that the auxin treatment generated an increase in sensitivity by a factor of up to 100,000, whereas in untransformed protoplasts the same auxin treatment induced an increase in auxin sensitivity that never exceeded 30- to 50-fold. This reflects a strong cooperative effect of auxin and rolB in transformed protoplasts. Surprisingly, the maximal increase in sensitivity was observed several hours before the maximal accumulation of rolB mRNA, suggesting that the dramatic control of auxin sensitivity by auxin in rolB-transformed protoplasts requires only low levels of rolB expression. Antibodies directed against ZmER-abp1, the major auxin-binding protein from maize, differentially altered the auxin sensitivity of the electrical response of rolB-transformed and normal protoplasts. This suggests that alterations of the auxin reception-transduction pathway at the plasma membrane of rolB-transformed protoplasts may account for their increased auxin sensitivity.
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- Aviv H., Leder P. Purification of biologically active globin messenger RNA by chromatography on oligothymidylic acid-cellulose. Proc Natl Acad Sci U S A. 1972 Jun;69(6):1408–1412. doi: 10.1073/pnas.69.6.1408. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Capone I., Cardarelli M., Mariotti D., Pomponi M., De Paolis A., Costantino P. Different promoter regions control level and tissue specificity of expression of Agrobacterium rhizogenes rolB gene in plants. Plant Mol Biol. 1991 Mar;16(3):427–436. doi: 10.1007/BF00023993. [DOI] [PubMed] [Google Scholar]
- Delbarre A., Muller P., Imhoff V., Barbier-Brygoo H., Maurel C., Leblanc N., Perrot-Rechenmann C., Guern J. The rolB Gene of Agrobacterium rhizogenes Does Not Increase the Auxin Sensitivity of Tobacco Protoplasts by Modifying the Intracellular Auxin Concentration. Plant Physiol. 1994 Jun;105(2):563–569. doi: 10.1104/pp.105.2.563. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ephritikhine G., Barbier-Brygoo H., Muller J. F., Guern J. Auxin effect on the transmembrane potential difference of wild-type and mutant tobacco protoplasts exhibiting a differential sensitiity to auxin. Plant Physiol. 1987 Apr;83(4):801–804. doi: 10.1104/pp.83.4.801. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Han J. H., Stratowa C., Rutter W. J. Isolation of full-length putative rat lysophospholipase cDNA using improved methods for mRNA isolation and cDNA cloning. Biochemistry. 1987 Mar 24;26(6):1617–1625. doi: 10.1021/bi00380a020. [DOI] [PubMed] [Google Scholar]
- Jefferson R. A., Kavanagh T. A., Bevan M. W. GUS fusions: beta-glucuronidase as a sensitive and versatile gene fusion marker in higher plants. EMBO J. 1987 Dec 20;6(13):3901–3907. doi: 10.1002/j.1460-2075.1987.tb02730.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shen W. H., Davioud E., David C., Barbier-Brygoo H., Tempé J., Guern J. High Sensitivity to Auxin is a Common Feature of Hairy Root. Plant Physiol. 1990 Oct;94(2):554–560. doi: 10.1104/pp.94.2.554. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spanò L., Mariotti D., Cardarelli M., Branca C., Costantino P. Morphogenesis and Auxin Sensitivity of Transgenic Tobacco with Different Complements of Ri T-DNA. Plant Physiol. 1988 Jun;87(2):479–483. doi: 10.1104/pp.87.2.479. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Trovato M., Cianfriglia M., Filetici P., Mauro M. L., Costantino P. Expression of Agrobacterium rhizogenes rolB gene fusions in Escherichia coli: production of antibodies against the RolB protein. Gene. 1990 Mar 1;87(1):139–143. doi: 10.1016/0378-1119(90)90506-m. [DOI] [PubMed] [Google Scholar]
- Venis M. A., Napier R. M., Barbier-Brygoo H., Maurel C., Perrot-Rechenmann C., Guern J. Antibodies to a peptide from the maize auxin-binding protein have auxin agonist activity. Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):7208–7212. doi: 10.1073/pnas.89.15.7208. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Venis M. A., Napier R. M. Plant hormone receptors: past, present and future. Biochem Soc Trans. 1992 Feb;20(1):55–59. doi: 10.1042/bst0200055. [DOI] [PubMed] [Google Scholar]