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Physiological consequences of mutation for ALS-inhibitor resistance

  • Charlotte V. Eberlein, Mary J. Guttieri (a1), Philip H. Berger (a2), John K. Fellman (a3), Carol A. Mallory-Smith (a4), Donn C. Thill (a2), Roger J. Baerg (a1) and William R. Belknap (a5)...


Biochemical and physiological effects of target site resistance to herbicides inhibiting acetolactate synthase (ALS) were evaluated using sulfonylurea-resistant (R) and -susceptible (S) near isonuclear Lactuca sativa ‘Bibb’ lines derived by backcrossing the resistance allele from Lactuca serriola L. into L. sativa. Sequence data suggest that resistance in L. sativa is conferred by a single-point mutation that encodes a proline197 to histidine substitution in Domain A of the ALS protein; this is the same substitution observed in R L. serriola. K mapp (pyruvate) values for ALS isolated from R and S L. sativa were 7.3 and 11.1 mM, respectively, suggesting that the resistance allele did not alter the pyruvate binding domain on the ALS enzyme. Both R and S ALS had greater affinity for 2-oxobutyrate than for pyruvate at the second substrate site. Ratios of acetohydroxybutyrate: acetolactate produced by R ALS across a range of 2-oxobutyrate concentrations were similar to acetohydroxybutyrate: acetolactate ratios produced by S ALS. Specific activity of ALS from R L. sativa was 46% of the specific activity from S L. sativa, suggesting that the resistance allele has detrimental effects on enzyme function, expression, or stability. ALS activity from R plants was less sensitive to feedback inhibition by valine, leucine, and isoleucine than ALS from S plants. Valine, leucine, and isoleucine concentrations were about 1.5 times higher in R seed than in S seed on a per gram of seed basis, and concentrations of valine and leucine were 1.3 and 1.6 times higher, respectively, in R leaves than in S leaves. Findings suggest that the mutation for resistance results in altered regulation of branched-chain amino acid synthesis.


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Corresponding author. University of Idaho Twin Falls Research and Extension Center, P.O. Box 1827, Twin Falls, ID 83303;


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Bernasconi, P., Woodworth, A. R., Rosen, B. A., Subramanian, M. V., and Siehl, D. H. 1996. A naturally occurring point mutation confers broad range tolerance to herbicides that target acetolactate synthase. J. Biol. Chem. 270:1738117385. [Correction J. Biol. Chem. 27:13925.]
Chipman, D. M., Gollop, N., Damri, B., and Barak, Z. 1990. Kinetics and mechanism of acetohydroxyacid synthases. Pages 243267 in Barak, Z., Chipman, D. M., and Schloss, J. V., eds. Biosynthesis of Branched Chain Amino Acids. Rehovot, Israel: Balaban Publishers.
Delfourne, E., Bastide, J., and Genix, P. 1994. Specificity of plant acetohydroxyacid synthase: formation of products and inhibition by herbicides. Plant Physiol. Biochem. 32:473477.
Dyer, W. E., Chee, P. W., and Fay, P. K. 1993. Rapid germination of sulfonylurea-resistant Kochia scoparia is associated with elevated seed levels of branched-chain amino acids. Weed Sci. 41:1822.
Eberlein, C. V., Guttieri, M. J., Mallory-Smith, C. A., Thill, D. C., and Baerg, R. J. 1997. Altered acetolactatc synthase activity in ALS-inhibitor resistant prickly lettuce (Lactuca serriola). Weed Sci. 45:212217.
Frohman, M. A. 1990. RACE: rapid amplification of cDNA ends. Pages 2838 in Innis, M. A., Geland, D. H., Sninsky, J. J., White, T. J., eds. PCR Protocols: A Guide to Methods and Amplifications. San Diego: Academic Press.
Gollop, N., Chipman, D. M., and Barak, Z. 1983. Inhibition of acetohydroxy acid synthase by leucine. Biochim. Biophys. Acta 749:3439.
Gollop, N., Damri, B., Barak, Z., and Chipman, D. 1989. Kinetics and mechanisms of acetohydroxy acid synthase isozyme III from Escherichia coli . Biochemistry 28:63106317.
Guttieri, M. J., Eberlein, C. V., Mallory-Smith, C. A., and Thill, D. C. 1996. Molecular genetics of target site resistance to acetolactate synthase-inhibiting herbicides. Pages 1016 in Brown, T. M., ed. Molecular Genetics and Ecology of Pesticide Resistance. Washington, D.C.: ACS Press.
Guttieri, M. J., Eberlein, C. V., Mallory-Smith, C. A., Thill, D. C., and Hoffman, D. C., 1992. DNA sequence variation in Domain A of the acetolactatc synthase genes of herbicide-resistant and -susceptible weed biotypes. Weed Sci. 40:670678.
Guttieri, M. J., Eberlein, C. V., and Thill, D. C. 1995. Diverse mutations in the acetolactate synthase gene confer chlorsulfuron resistance in kochia (Kochia scoparia) biotypes. Weed Sci. 43:175178.
Magee, P. T. and de Robichon-Szulmajster, H. 1968. The regulation of isoleucine-valine biosynthesis in Saccharomyces cerevisiae. 3. Properties and regulation of the activity of acetohydroxy-acid synthetase. Eur. J. Biochem. 3:507511.
Mallory-Smith, C. A. 1990. Identification and inheritance of sulfonylurea herbicide-resistance in prickly lettuce (Lactuca serriola L.). Ph.D. thesis. University of Idaho, Moscow, ID. 58 p.
Mallory-Smith, C. A., Thill, D. C., and Dial, M. J. 1990. Identification of sulfonylurea herbicide-resistant prickly lettuce (Lactuca serriola). Weed Technol. 4:163168.
Mallory-Smith, C., Thill, D. C., and Dial, M. J. 1993. ID-BR1: sulfonylurea herbicide-resistant lettuce germplasm. Hortic. Sci. 28:6364.
Mazur, B. J., Chui, C.-F., and Smith, J. K. 1987. Isolation and characterization of plant genes coding for acetolactate synthase, the target enzyme for two classes of herbicides. Plant Physiol. 85:11101117.
Miflin, B. J. and Cave, P. R. 1972. The control of leucine, isoleucine, and valine biosynthesis in a range of higher plants. J. Exp. Bot. 23:511516.
Mourad, G., Williams, D., and King, J. 1995. A double mutant allele, csr 1–4, of Arabidopsis thaliana encodes an acetolactatc synthase with altered kinetics. Planta 196:6468.
Muhitch, M. J. 1988. Acetolactate synthase activity in developing maize (Zea mays L.) kernels. Plant Physiol. 86:2327.
Newhouse, K., Singh, B., and Shaner, D. 1991. Mutations in corn (Zea mays L.) conferring resistance to imidazolinone herbicides. Theor. Appl. Genet. 83:6570.
Newhouse, K. E., Smith, W. A., Starett, M. A., Schaefer, T. J., and Singh, B. K. 1992. Tolerance to imidazolinone herbicides in wheat. Plant Physiol. 100:882886.
Rathinasabapathi, B. and King, J. 1991. Herbicide resistance in Datura innoxia . Kinetic characterization of acetolactate synthase from wild type and sulfonylurea variants. Plant Physiol. 96:255261.
Rathinasabapathi, B., Williams, D., and King, J. 1990. Altered feedback sensitivity to valine, leucine, and isoleucine of acetolactate synthase from herbicide-resistant variants of Datura innoxia . Plant Sci. 67:16.
Relton, J. M., Wallsgrove, R. M., Bourgin, J. P., and Bright, S.W.J. 1986. Altered feedback sensitivity of acetohydroxyacid synthase from valineresistant mutants of tobacco (Nicotiana tabacum L.). Planta 169:4650.
Rost, T. L., Gladish, D., Steffen, J., and Robbins, J. 1990. Is there a relationship between branched chain amino acid pool size and cell cycle inhibition in roots treated with imidazolinone herbicides? J. Plant Growth Regul. 9:227232.
Saari, L. L., Cotterman, J. C., and Primiani, M. M. 1990. Mechanisms of sulfonylurea herbicide resistance in the broadleaf weed, Kochia scoparia . Plant Physiol. 93:5561.
Saari, L. L., Cotterman, J. C., Smith, W. F., and Primiani, M. M. 1992. Sulfonylurea herbicide resistance in common chickweed, perennial ryegrass, and Russian thistle. Pestic. Biochem. Physiol. 42:110118.
Saari, L. L., Cotterman, J. C., and Thill, D. C. 1994. Resistance to acetolactate synthase-inhibitor herbicides. Pages 83139 in Powles, S. B. and Holtum, J.A.M., eds. Herbicide Resistance in Plants: Biology and Biochemistry. Boca Raton, FL: Lewis Publishers.
Schloss, J. V. 1990. Acetolactate synthase, mechanism of action and its herbicide binding site. Pestic. Sci. 29:283292.
Shaner, D. L. 1991. Physiological effects of the imidazolinone herbicides. Pages 129137 in Shaner, D. L. and O'Connor, S. L., eds. The Imidazolinone Herbicides. Boca Raton, FL: CRC Press.
Shaner, D. L. and Singh, B. K. 1993. Phytotoxicity of acetohydroxyacid synthase inhibitors is not due to accumulation of 2-ketobutyrate and/or 2-amino butyrate. Plant Physiol. 103:12211226.
Siehl, D. L., Bangston, A. S., Brockman, J. P., Butler, J. H., Kraatz, G. W., Lamoreaux, R. J., and Subramanian, M. V. 1996. Patterns of cross tolerance to herbicides inhibiting acetohydroxyacid synthase in commercial corn varieties designed for tolerance to imidazolinones. Crop Sci. 36:274278.
Singh, B. K. and Shaner, D. L. 1995. Biosynthesis of branched chain amino acids: from test tube to field. Plant Cell 7:935944.
Subramanian, M. V., Hung, H., Dias, J. M., Miner, V. W., Butler, J. H., and Jachetta, J. J. 1990. Properties of mutant acetolactate synthases resistant to triazolopyrimidine sulfonanilide. Plant Physiol. 94:239244.
Subramanian, M. V., Loney-Gallant, V., Dias, J. M., and Mireles, L. C. 1991. Acetolactate synthase inhibiting herbicides bind to the regulatory site. Plant Physiol. 96:310313.
Verwoerd, T. C., Dekker, D.M.M., and Hoekema, A. 1989. A small-scale procedure for the rapid isolation of plant RNAs. Nucl. Acids Res. 17:2362.


Physiological consequences of mutation for ALS-inhibitor resistance

  • Charlotte V. Eberlein, Mary J. Guttieri (a1), Philip H. Berger (a2), John K. Fellman (a3), Carol A. Mallory-Smith (a4), Donn C. Thill (a2), Roger J. Baerg (a1) and William R. Belknap (a5)...


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