Where is abscisic acid synthesis

Plant Physiology 95 , — Do chloroplasts play a role in abscisic acid synthesis? Plant Science Letters 22 , — Plant Physiology , — Hoad GV. Effect of moisture stress on abscisic acid levels in Ricinus communis L. The site of carotenogenic enzymes in chromoplasts from Narcissus pseudonarcissus L.

Planta , 66 — Tetrahedron Letters 39 , — Endogenous biosynthetic precursors of abscisic acid. Australian Journal of Plant Physiology 24 , — Molybdenum cofactor mutants, specifically impaired in xanthine dehydrogenase activity and abscisic acid biosynthesis, simultaneously overexpress nitrate reductase.

Li Y, Walton DC. Plant Physiology 92 , — Two independent biochemical pathways for isopentenyl diphosphate and isoprenoid biosynthesis in higher plants. Physiologia Plantarum , — Biosynthesis of isoprenoids in higher plant chloroplasts proceeds via a mevalonate independent pathway.

FEBS Letters , — Plant, Cell and Environment 10 , — Phvtochemistry 26 , — Evidence of photosynthetic origin of monoterpenes emitted by Quercus ilex L. Loveys BR. Physiologia Plantarum 40 , 6 — Molecular identification of zeaxanthin epoxidase of Nicotiana plumbaginifolia , a gene involved in abscisic acid biosynthesis and corresponding to the ABA locus of Arabidopsis thaliana.

EMBO Journal 15 , — McCaskill D, Croteau R. Milborrow BV. The metabolism of abscisic acid. Journal of Experimental Botany 21 , 17 — Stereochemical aspects of the formation of double bonds in abscisic acid. Biochemical Journal , — Phytochemistry 13 , — Milborrow B V. Abscisic acid and other hormones. The physiology and biochemistry of drought resistance in plants. Sydney: Academic Press, — The conformation of abscisic acid by NMR and a revision of the proposed mechanism for cyclisation during its biosynthesis.

Xanthoxal: a revision of the nomenclature of the ABA precursor xanthoxin. Phytochemistry 44 , — Phytochemistry 45 , — Milborrow BV, Garmston M.

Phytochemistry 12 , — Australian Journal of Plant Physiology 25 , — Plant Science 56 , 49 — Factors affecting the biosynthesis of abscisic acid.

Journal of Experimental Botany 24 , — Australian Journal of Plant Physiology 9 , — Munns R, Sharp RE. Involvement of abscisic acid in controlling plant growth in soils of low water potential. Australian Journal of Plant Physiology 20 , — Neill SJ, Horgan R. Abscisic acid production and water relations in wilty tomato mutants subjected to water deficiency. Journal of Experimental Botany 36 , — The biosynthesis of abscisic acid in Cercospora rosicola.

Phytochemistry 21 , 61 — The isolation and identification of the prosthetic group released from a bound form of abscisic acid. Plant Growth Regulation 11 , — Incorporation of 2 H from 2 H 2 O and 18 O 2 into precursors. Journal of Experimental Botany 38 , — Expression of nuclear genes as affected by treatments acting on plastics. Xanthoxin levels and metabolites in the wild type and wilty mutants of tomato.

EMBO Journal 16 , — Evidence of plastid control of abscisic acid accumulation in barley Hordeum vulgare L. Effects of inhibitors of protein synthesis on abscisic acid accumulation in wheat. Journal of Experimental Botany 47 , — Robinson DR, Ryback G. Abscisic alcohol is an intermediate in abscisic acid biosynthesis in a shunt pathway from abscisic aldehyde. Plant Physiology 97 , — Plant Physiology 93 , — Rohmer M.

The discovery of a mevalonate independent pathway for isoprenoid biosynthesis in bacteria, algae and higher plants.

Natural Product Reports 16 , — Isoprenoid biosynthesis in bacteria: a novel pathway for the early steps leading to isopentenyl diphosphate. Aldehyde oxidase and xanthine dehydrogenase in a flacca tomato mutant with deficient abscisic acid and wilty phenotype. Sanchez SM.

The fine structure of the guard cells of Helianthus annuus. American Journal of Botany 64 , — Biochemical characterization of the aba2 and aba3 mutants in Arabidopsis thaliana. Specific oxidative cleavage of carotenoids by VP 14 of maize. Biochemical Journal , 73 — Compartmentation of terpenoid biosynthesis in green plants. Abscisic aldehyde is an intermediate in the enzymatic conversion of xanthoxin to abscisic acid in Phaseolus vulgaris L.

Plant Physiology 88 , — Uptake of isopentenyl diphosphate by plastids isolated from V itis vinifera L. Genetic control of abscisic acid biosynthesis in maize. Xanthoxin, a new naturally occurring plant growth inhibitor. Xanthoxin, a recently discovered plant growth inhibitor. Proceedings of the Royal Society of London B , — Vittone V, Milborrow BV. Does abscisic acid occur free in leaf cells?

Reduced accumulation of ABA during water stress in a molybdenum cofactor mutant of barley. Plant Physiology 90 , — Warganegara F, Milborrow BV. Phytochemistry 28 , — Abscisic aldehyde: a new synthesis, isotopic labelling, exchange reactions and oxidation. Phytochemistry 31 , — Wright DL. Biosynthesis of isoprenoid compounds. Annual Review of Biochemistry 30 , — Wright STC. Zeevaart JAD. Sites of abscisic acid synthesis and metabolism in Ricinus communis L.

Plant Physiology 59 , — Phytochemistry 15 , — Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Sign In. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation.

Volume Article Contents Abstract. Intermediates in the biosynthesis of ABA. Reactions forming ABA. The pathway of biosynthesis of abscisic acid in vascular plants: a review of the present state of knowledge of ABA biosynthesis.

Milborrow B. Oxford Academic. Cite Cite B. Select Format Select format. Permissions Icon Permissions. Biosynthesis pathway , abscisic acid , vascular plants. Open in new tab Download slide. ABA synthesis represents a minor branch of the carotenoid pathway; as originally indicated by a number of pioneering experiments Taylor and Burden, It is therefore important to note that the ultimate precursor of ABA is not mevalonic acid. This represents a major revision of the information given in many earlier reviews Milborrow, ; as has been pointed out more recently by a number of authors Milborrow and Lee, The ABA biosynthetic pathway can in some ways be regarded as starting from this xanthophyll Taylor, since mutants blocked downstream of zeaxanthin show symptoms typical of ABA, rather than carotenoid, deficiency.

Important evidence relating to the validity of the pathway shown in Fig. Endogenous ABA levels can be reduced using the carotenoid biosynthesis inhibitors, norflurazon and fluridone.

However, the virtually white seedlings which can be obtained following norflurazon and fluridone treatments are deficient in a whole range of metabolic processes resulting from the photobleaching of chlorophyll.

Against this background, the phenotypic effects of ABA deficiency seem trivial and ABA is not the limiting factor preventing continued growth. Comprehensive information on these important experiments has been provided recently by three excellent reviews Cutler and Krochko, ; Liontenberg et al.

For this reason, considerable uncertainty remains concerning the precise route s followed prior to the formation of the first C 15 intermediate, xanthoxin. At present there is no clear experimental evidence available to demonstrate which of these alternative routes occurs in planta. It is important for this uncertainty to be resolved.

Characterization of mutants at this isomerization step would be likely to end some of the uncertainty which continues to surround this part of the pathway see the previous section and also Fig.

Because xanthophylls form important components of the photosynthetic apparatus it is misleading to consider them simply as precursors of ABA. Nevertheless, it is reasonable to point out that the most obvious abnormalities of mutants which are impaired in the epoxidation of zeaxanthin Duckham et al. There is strong evidence that the vp14 mutant of maize Tan et al. It is likely that the wilty mutant of pea also affects this first committed step in the ABA pathway, although wilty pea has not yet been fully characterized.

In contrast, a much larger and more diverse collection of mutants are known to be impaired in the oxidation of ABAld to form ABA. The sit mutant of tomato accumulates the biologically inactive compound trans ABA alcohol instead of ABA in response to water stress Linforth et al. Virtually identical results were obtained for the droopy mutant of Solanum phureja , which appears to occupy an equivalent position in the potato genome to the sit gene locus on the short arm of chromosome 1 of tomato Duckham et al.

Recently, strong evidence has been obtained that a mutant of Arabidopsis , previously known as v11 and now renamed aao3 , is also impaired in the apoenzyme of ABAO Seo et al. The second category has been referred to as affecting MoCo maturation, following the review by Mendel and Schwarz Mendel and Schwarz, These authors regard the cofactor containing the dioxo form of Mo as the end product of MoCo biosynthesis.

This is the form of the cofactor which is incorporated into the nitrate reductase apoprotein. After parallel incorporation of MoCo into aldehyde oxidase and xanthine dehydrogenase apoproteins, a sulphurylase adds inorganic sulphur to the Mo centre converting dioxo MoCo to the monooxo form.

Mutants affecting MoCo synthesis and maturation have been discussed recently Mendel and Schwarz, As they are indirectly, rather than directly, associated with ABA biosynthesis these mutants will not be considered further in this review. These categories will be discussed in turn. The first major breakthrough in understanding the molecular genetics of ABA biosynthesis involved the cloning of zeaxanthin epoxidase Marin et al. A plant was identified which exhibited an unstable wilty mutant phenotype.

The stable mutant plants accumulated very high levels of zeaxanthin and had abnormally low concentrations of the epoxyxanthophylls, i. A virtually identical pattern of xanthophyll abnormalities was reported previously for the Arabidopsis mutant aba1 Duckham et al. In addition, this construct complemented the Arabidopsis aba1 genetic lesion.

These are orthologous mutants, both impaired in the synthesis of the enzyme zeaxanthin epoxidase ZEP. The complete open reading frames encoding ZEP have been reported for pepper Bouvier et al. An internal 1. Changes in transcript level during development at different times of day and also in response to water stress, were determined in detail in this species Audran et al.

Similar general conclusions can be drawn from both of these studies. Audran et al. As with N. A Western blot analysis was carried out in N. Although superficially surprising, this could have resulted from putative rises in newly synthesized ZEP being obscured by high background levels of stable ZEP protein.

This demonstrates the importance of designing experiments with suitable controls to allow for these time of day effects.

In both N. Because the products of ZEP , the epoxyxanthophylls e. The epoxyxanthophyll levels in roots are much lower than in the leaves Parry and Horgan, and therefore could be limiting for sustained ABA synthesis. In the systems investigated so far, this appears to be true. Antisense constructs were produced based on a 1.

Northern analysis of leaves from homozygous transgenic N. Nevertheless, it was observed that two out of five transgenic lines obtained with the 0. Data were reported for two of the lines which showed the greatest effect on seed dormancy. Homozygous tomato transgenics carrying an LeZEP1 antisense construct have been produced Parker et al.

However, in combination with notabilis the antisense transgene produced an extremely wilty phenotype. Because tomato seeds have almost no dormancy, in contrast to those of N. However, the mature flowers of tomato which are normally bright yellow have a much paler colour in the LeZEP1 antisense transformants. This was associated with the accumulation of zeaxanthin in the corolla Fig. Transgenic N. Note that flowers containing the transgenic antisense ZEP construct exhibit a reduced corolla pigmentation.

This involved characterization of the viviparous 14 vp14 gene locus in maize Zea mays. It is therefore difficult to overstate the importance of cloning this gene for studies on the control of ABA biosynthesis. Complete or partial precocious germination of seeds on the cob was used as a screen for new viviparous mutants; a phenotype which can be caused by genetic lesions in ABA biosynthesis. Two new viviparous mutants showed some signs of precocious germination but did not emerge fully on the cob.

Complementation testing showed that the two mutant lines were allelic with each other, but not with any other known viviparous mutants. The new mutant alleles were termed vp14— and vp14— Further molecular analyses showed that in vp14— the Mu1 element had integrated into the coding sequence, completely disrupting the ORF, resulting in a null allele. The ORF of the Vp14 gene contains no introns and has a deduced sequence of amino acids Tan et al.

These and many other amino acid sequence homologies are consistent with VP14 encoding a dioxygenase Schwartz et al. More direct proof that VP14 was specifically involved in the oxidative cleavage reaction in ABA biosynthesis was obtained by producing a recombinant VP14 protein in E. Subsequent analysis of leaf xanthophyll levels revealed no abnormalities in not mutant homozygotes Parry et al.

From this it could be inferred that not mutants were probably impaired in the same step of the pathway as the vp14 mutant of maize. Degenerate primers were designed D McCarty, personal communication based on the two conserved motifs between VP14 and LSD which were discussed in the previous paragraph.

Since then reports have appeared describing NCED gene expression in tomato, Arabidopsis and in bean Phaseolus vulgaris. A number of general conclusions can be drawn from these studies.

This was not the case with LeNCED1 mRNA which remained at a low level throughout the extended dark period, showing no sign that it was being controlled by a circadian oscillator. It appears that this gene is subject to control by a mechanism that is sensitive to light and dark, but is otherwise insensitive to the time of day Thompson et al. Further experiments should also be carried out to test for possible diurnal fluctuations in NCED mRNAs at high relative humidity, when fluctuations in water potential have been prevented.

If such studies confirm that there is a genuine light effect, then the phenomenon requires an explanation. It is conceivable that the plant prepares for a possible emergency requirement for ABA biosynthesis by turning on this gene at dawn. The plant may anticipate that water stress would most likely occur during the day. The levels were relatively low at In both the tomato and the bean, these changes preceded a rise in ABA levels in the leaves.

The rapidity of the responses in both tomato and bean leaves, suggests that an initial reduction in turgor almost instantly triggers expression of this gene; which therefore must be extremely pressure sensitive.

Bean roots responded similarly to those of tomato, when they were detached and subjected to osmotic stress Qin and Zeevaart, This aspect of NCED expression has not yet been investigated as thoroughly as the dramatic response to water stress. A number of studies on this topic are likely to be published shortly.

A total of 61 independent primary transformants have been obtained Thompson et al. Another group of 19 plants appeared to be normal and have not been investigated further. Under these conditions three of the transformants grew slowly and were observed to guttate, i.

Increased volumes of xylem sap flowing from the roots to the shoots, combined with stomatal closure, probably results in exudation from the hydathodes at the leaf margins. Syntheses of optically active acetylenic analogs of abscisic acid I are described. The key step involves the diastereoselective alkylation of the 2S,3S -butanediol ketal of oxoisophorone II , which produces a mixt. The abs. Concise enantioselective synthesis of abscisic acid and a new analogue.

Smith, Timothy R. The syntheses proceed through key intermediates that preferentially recrystallize as single diastereoisomers for each enantiomer and Sonogashira cross coupling. This route allows the prepn. Catalysts , 8 , , DOI: Abscisic acid ABA is a natural product, which is a well-known phytohormone. However, this mol. The strategy here relies on a palladium-catalyzed Mizoroki-Heck cross-coupling as key reaction performed in solvent and ligand free conditions.

The new chiral epoxidn. It gives uniformly high asym. Acta , 71 , — , DOI: The novel violadione III was prepd. Base treatment of III gave violadienedione IV, a potential precursor of carotenoids with phenolic end groups.

Convenient synthesis of optically active abscisic acid and xanthoxin. Tetrahedron , 48 , — , DOI: The Reformatskii reaction of 3- bromomethyl crotonate with an optically active epoxycyclohexane aldehyde deriv. Synthesis of Abscisic Acid. Acta , 59 , — , DOI: A four-step synthesis of abscisic acid I is described, with a yield of The two starting materials are known compds. II is prepd. The synthesis involves a Reformatskii reaction, epoxide formation, a ketal hydrolysis, and an elimination that accompanies an epoxide rearrangement.

Synthesis of Violet Perfumes. Justus Liebigs. Isopropylideneacetoacetic Ester: The preparation method of Pauly was improved; 6 kg.

Formula III is rejected on account of the great instability of isophoronecarboxylic acid. The action of these upon 85 g. AcOEt, Ethyl trimethylacrylate b. Ethyl Isophoronecarboxylate IV is preloared by the condensation of ethylisopropylideneacetoacetate and ethyl acetoacetate. Thick yellowish oil, b3. It exists in the ketonic and enolic forms. Ketonic form b Isophoronecarboxylic acid is obtained by saponifying the ester in the cold with alc.

Ethyl ethylisophoronecarboxylate V colorless odorless oil. One carbinol was obtained pure. Colorless powder or prisms, m. Oxalylhydroxycarbinol, C12H18O4, fine crystalline powder, m. Group A, Cis-acid. Isolated as the lactone, m. This leaves, m. On distillation in vacuo goes over mostly into its trans- form. Acetate, C12H20O4, prisms, m.

Trans-acid, C10H18O8, prisms, m. Yield nearly quantitative. Thick tables, m. Cis-acid, C10OH18O3, small glistening crystals, m. Ethyl ester, C12H22O3, viscous oil, b5 Trans-acid, crystals, m. Acetate, prisms, m. Lactone, C10H15O2, crystals, m. The keto esters were prepared by means of Beckmann's solution. Oxime, C12H21O8 N, prisms, m. Oxime, m. Configuration of the Stereoisomers: Theoretical discussion.

Cis-hydroxy acid C, C10H18O3, prisms or needles, m. Ethyl ester, C12H22O3, thick oil. Trans-hydroxy acid C, prisms, m. Ethyl ester, thick oil, b6 Lactone, C10H16O2, large crystals resembling tartaric acid, m. Best prepared by distilling cis-hydroxy acid C in vacuo. Cis- and trans-acids are oxidized to the same keto acid C, C10H16O3, needles.

Oxime, crystals, m. Dibenzal derivative, C26H28O3, yellow needles, m. Description of methods used. Intermediates in the Synthesis of Xanthophyll and Zeaxanthin. Several reactions are described in the attempted prepn. The synthesis of ethyl 2,6,6-trimethyloxocyclohexenecarboxylate I is described. I could serve as a suitable starting material for the prepn. Condensation of mesityl oxide with acetoacetic ester. The zinc chloride catalyzed condensation of mesityl oxide with ethyl aceto acetate resulted in the formation of two structural isomers: Et 3,5,5-tr imethylcyclohexenonecarboxylate and Et 3,5,5-trimethylcyclohexenonecarboxylate I was readily converted to isophorone by selective hydrolysis.

Selective thioketalization of a mixt. The LiAlH4 redn. MnO2 oxidn. Novel Syntheses of Isomers of Damascenone from Ethyl 2,6,6-Trimethyloxocyclohexenecarboxylate. Korean Chem. American Chemical Society. A one-pot annulation method for prepn. OTf efficiently induced oxidn. Tetrahedron , 66 , — , DOI: A review discusses the synthesis of Hagemann's ester I and related compds. Tetrahedron , 29 , — , DOI: Canadian Science Publishing.

A large no. A Z-selective Knoevenagel condensation can be achieved by the use of tert-Bu acetoacetate with either arom. Acta , 31 , — , DOI: German ; cf. Refluxing 6 h. K and cc. Fairly pure IV b0. IV P2O5 in cc. PhMe yields 5. III, from II by sapon. Chemical Reviews Washington, D. The following reaction pathways are considered: vinylogous aldol addns. Synlett , — , DOI: Application in synthesis. Georg Thieme Verlag. A review with many refs. Of particular use is that furan-, pyrrole-, and thiophene-derived 2-silyl-oxy dienes, our research group was exploiting for about a decade, undergo regio- and stereoselective vinylogous cross-aldol or Mannich-type reactions with prodn.

This account surveys salient achievements our lab. Elsevier Science Ltd. In methylene-deoxo-bisubstitution reactions Knoevenagel, Stobbe, etc. Hence, a synthesis of 13Z retinoic acids is described, via a stereospecific monodecarboxylation of carboxyretinoic acids. Tetrahedron , 56 , — , DOI: Valla, A.