Skip to main content
NCBI home page
The Plant Cell logoLink to The Plant Cell
. 1997 Oct;9(10):1781–1790. doi: 10.1105/tpc.9.10.1781

Arabidopsis mutants resistant to the auxin effects of indole-3-acetonitrile are defective in the nitrilase encoded by the NIT1 gene.

J Normanly 1, P Grisafi 1, G R Fink 1, B Bartel 1
PMCID: PMC157021  PMID: 9368415

Abstract

Indole-3-acetonitrile (IAN) is a candidate precursor of the plant growth hormone indole-3-acetic acid (IAA). We demonstrated that IAN has auxinlike effects on Arabidopsis seedlings and that exogenous IAN is converted to IAA in vivo. We isolated mutants with reduced sensitivity to IAN that remained sensitive to IAA. These mutants were recessive and fell into a single complementation group that mapped to chromosome 3, within 0.5 centimorgans of a cluster of three nitrilase-encoding genes, NIT1, NIT2, and NIT3. Each of the three mutants contained a single base change in the coding region of the NIT1 gene, and the expression pattern of NIT1 is consistent with the IAN insensitivity observed in the nit1 mutant alleles. The half-life of IAN and levels of IAA and IAN were unchanged in the nit1 mutant, confirming that Arabidopsis has other functional nitrilases. Overexpressing NIT2 in transgenic Arabidopsis caused increased sensitivity to IAN and faster turnover of exogenous IAN in vivo.

Full Text

The Full Text of this article is available as a PDF (1.8 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bartel B., Fink G. R. Differential regulation of an auxin-producing nitrilase gene family in Arabidopsis thaliana. Proc Natl Acad Sci U S A. 1994 Jul 5;91(14):6649–6653. doi: 10.1073/pnas.91.14.6649. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bartel Bonnie. AUXIN BIOSYNTHESIS. Annu Rev Plant Physiol Plant Mol Biol. 1997 Jun;48(NaN):51–66. doi: 10.1146/annurev.arplant.48.1.51. [DOI] [PubMed] [Google Scholar]
  3. Bartling D., Seedorf M., Mithöfer A., Weiler E. W. Cloning and expression of an Arabidopsis nitrilase which can convert indole-3-acetonitrile to the plant hormone, indole-3-acetic acid. Eur J Biochem. 1992 Apr 1;205(1):417–424. doi: 10.1111/j.1432-1033.1992.tb16795.x. [DOI] [PubMed] [Google Scholar]
  4. Bartling D., Seedorf M., Schmidt R. C., Weiler E. W. Molecular characterization of two cloned nitrilases from Arabidopsis thaliana: key enzymes in biosynthesis of the plant hormone indole-3-acetic acid. Proc Natl Acad Sci U S A. 1994 Jun 21;91(13):6021–6025. doi: 10.1073/pnas.91.13.6021. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Fracheboud Y., King P. J. An auxin-auxotrophic mutant of Nicotiana plumbaginifolia. Mol Gen Genet. 1991 Jul;227(3):397–400. doi: 10.1007/BF00273929. [DOI] [PubMed] [Google Scholar]
  6. Hillebrand H., Tiemann B., Hell R., Bartling D., Weiler E. W. Structure of the gene encoding nitrilase 1 from Arabidopsis thaliana. Gene. 1996 May 8;170(2):197–200. doi: 10.1016/0378-1119(95)00839-x. [DOI] [PubMed] [Google Scholar]
  7. 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]
  8. Kobayashi M., Komeda H., Yanaka N., Nagasawa T., Yamada H. Nitrilase from Rhodococcus rhodochrous J1. Sequencing and overexpression of the gene and identification of an essential cysteine residue. J Biol Chem. 1992 Oct 15;267(29):20746–20751. [PubMed] [Google Scholar]
  9. Kobayashi M., Yanaka N., Nagasawa T., Yamada H. Primary structure of an aliphatic nitrile-degrading enzyme, aliphatic nitrilase, from Rhodococcus rhodochrous K22 and expression of its gene and identification of its active site residue. Biochemistry. 1992 Sep 22;31(37):9000–9007. doi: 10.1021/bi00152a042. [DOI] [PubMed] [Google Scholar]
  10. Lam H. M., Coschigano K., Schultz C., Melo-Oliveira R., Tjaden G., Oliveira I., Ngai N., Hsieh M. H., Coruzzi G. Use of Arabidopsis mutants and genes to study amide amino acid biosynthesis. Plant Cell. 1995 Jul;7(7):887–898. doi: 10.1105/tpc.7.7.887. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Last R. L., Fink G. R. Tryptophan-Requiring Mutants of the Plant Arabidopsis thaliana. Science. 1988 Apr 15;240(4850):305–310. doi: 10.1126/science.240.4850.305. [DOI] [PubMed] [Google Scholar]
  12. Llić N., Normanly J., Cohen J. D. Quantification of free plus conjugated indoleacetic acid in arabidopsis requires correction for the nonenzymatic conversion of indolic nitriles. Plant Physiol. 1996 Jul;111(3):781–788. doi: 10.1104/pp.111.3.781. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Michalczuk L., Ribnicky D. M., Cooke T. J., Cohen J. D. Regulation of indole-3-acetic Acid biosynthetic pathways in carrot cell cultures. Plant Physiol. 1992 Nov;100(3):1346–1353. doi: 10.1104/pp.100.3.1346. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Niyogi K. K., Last R. L., Fink G. R., Keith B. Suppressors of trp1 fluorescence identify a new arabidopsis gene, TRP4, encoding the anthranilate synthase beta subunit. Plant Cell. 1993 Sep;5(9):1011–1027. doi: 10.1105/tpc.5.9.1011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Normanly J., Slovin J. P., Cohen J. D. Rethinking Auxin Biosynthesis and Metabolism. Plant Physiol. 1995 Feb;107(2):323–329. doi: 10.1104/pp.107.2.323. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Pickett F. B., Wilson A. K., Estelle M. The aux1 Mutation of Arabidopsis Confers Both Auxin and Ethylene Resistance. Plant Physiol. 1990 Nov;94(3):1462–1466. doi: 10.1104/pp.94.3.1462. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Radwanski E. R., Barczak A. J., Last R. L. Characterization of tryptophan synthase alpha subunit mutants of Arabidopsis thaliana. Mol Gen Genet. 1996 Dec 13;253(3):353–361. doi: 10.1007/pl00008602. [DOI] [PubMed] [Google Scholar]
  18. Schmidt R. C., Müller A., Hain R., Bartling D., Weiler E. W. Transgenic tobacco plants expressing the Arabidopsis thaliana nitrilase II enzyme. Plant J. 1996 May;9(5):683–691. doi: 10.1046/j.1365-313x.1996.9050683.x. [DOI] [PubMed] [Google Scholar]
  19. Stasinopoulos T. C., Hangarter R. P. Preventing photochemistry in culture media by long-pass light filters alters growth of cultured tissues. Plant Physiol. 1990 Aug;93(4):1365–1369. doi: 10.1104/pp.93.4.1365. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. THIMANN K. V., MAHADEVAN S. NITRILASE. I. OCCURRENCE, PREPARATION, AND GENERAL PROPERTIES OF THE ENZYME. Arch Biochem Biophys. 1964 Apr;105:133–141. doi: 10.1016/0003-9861(64)90244-9. [DOI] [PubMed] [Google Scholar]
  21. Valvekens D., Van Montagu M., Van Lijsebettens M. Agrobacterium tumefaciens-mediated transformation of Arabidopsis thaliana root explants by using kanamycin selection. Proc Natl Acad Sci U S A. 1988 Aug;85(15):5536–5540. doi: 10.1073/pnas.85.15.5536. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Wilson A. K., Pickett F. B., Turner J. C., Estelle M. A dominant mutation in Arabidopsis confers resistance to auxin, ethylene and abscisic acid. Mol Gen Genet. 1990 Jul;222(2-3):377–383. doi: 10.1007/BF00633843. [DOI] [PubMed] [Google Scholar]
  23. Wright A. D., Sampson M. B., Neuffer M. G., Michalczuk L., Slovin J. P., Cohen J. D. Indole-3-Acetic Acid Biosynthesis in the Mutant Maize orange pericarp, a Tryptophan Auxotroph. Science. 1991 Nov 15;254(5034):998–1000. doi: 10.1126/science.254.5034.998. [DOI] [PubMed] [Google Scholar]

Articles from The Plant Cell are provided here courtesy of Oxford University Press

RESOURCES