The mode of inhibition of the biosynthesis of phenylalanine ammonia lyase by its product cinnamic acid in aging potato parenchyma tissue

Shirsat, S. G.; Nair, P.M.

doi:10.1007/bf02716654

Cited by 8 publications

(5 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To further unravel the role of pal genes during ripening in various fruit systems, the tissue‐specific and developmental expression of each gene family member has to be studied. Moreover, modulation of PAL activity, which caused the reduced level of the cinnamic acid derivatives, has already opened new avenues (Shirsat and Nair 1986). The identification and characterization of pal genes from a fruit cDNA library would certainly create an opportunity to explore the possible functions of multiple pal genes during fruit development.…”

Section: Phenylalanine Ammonia Lyase (Pal)mentioning

confidence: 99%

Phenylpropanoid Metabolism in Ripening Fruits

Singh¹,

Rastogi²,

Dwivedi³

2010

Comp Rev Food Sci Food Safe

175

128

View full text Add to dashboard Cite

Ripening of fleshy fruit is a differentiation process involving biochemical and biophysical changes that lead to the accumulation of sugars and subsequent changes in tissue texture. Also affected are phenolic compounds, which confer color, flavor/aroma, and resistance to pathogen invasion and adverse environmental conditions. These phenolic compounds, which are the products of branches of the phenylpropanoid pathway, appear to be closely linked to fruit ripening processes. Three key enzymes of the phenylpropanoid pathway, namely phenylalanine ammonia lyase, Omethyltransferase, and cinnamyl alcohol dehydrogenase (CAD) have been reported to modulate various end products including lignin and protect plants against adverse conditions. In addition, peroxidase, the enzyme following CAD in the phenylpropanoid pathway, has also been associated with injury, wound repair, and disease resistance. However, the role of these enzymes in fruit ripening is a matter of only recent investigation and information is lacking on the relationships between phenylpropanoid metabolism and fruit ripening processes. Understanding the role of these enzymes in fruit ripening and their manipulation may possibly be valuable for delineating the regulatory network that controls the expression of ripening genes in fruit. This review elucidates the functional characterization of these key phenylpropanoid biosynthetic enzymes/genes during fruit ripening processes.

show abstract

Section: Phenylalanine Ammonia Lyase (Pal)mentioning

confidence: 99%

Phenylpropanoid Metabolism in Ripening Fruits

Singh¹,

Rastogi²,

Dwivedi³

2010

Comp Rev Food Sci Food Safe

175

128

View full text Add to dashboard Cite

show abstract

“…In rye, PAL activity increased within minutes by decreasing the PAL inhibitor, transcinnamic acid through its isomerization to the cis form. This trans-cis shift is wavelength-dependent and may also be responsible for regulation of genetic transcription as shown in potato tissue (Shirsat and Nair, 1986). The isomerization of trans-cinnamoyl derivatives may protect seedlings within minutes of breaking through the soil surface, since the absorption of isolated epidermal layers is clearly shifted to a shorter wavelength by cis isomerization (Tevini et al, 1988b).…”

Section: Uv-protecting Pigmentsmentioning

confidence: 99%

Uv‐b Effects on Terrestrial Plants

Tevini

Teramura

1989

Photochem & Photobiology

555

224

View full text Add to dashboard Cite

DepartmentAbstract-The potential impacts of an increase in solar UV-B radiation reaching the Earth's surface due to stratospheric ozone depletion have been investigated by several research groups during the last 15 years. Much of this research has centered on the effects of plant growth and physiology undcr artificial UV-B irradiation supplied to plants in growth chambers or greenhouses. Since these artiticial sources do not precisely match the solar spectrum and due to the wavelength dependency of photobiological processes, weighting functions, based on action spectra for specific responses. have been developed to assess the biological effectiveness o f the irradiation sources and of predicted ozone depletion. Recent experiments have also utilized artificially produced ozonc cuvettes to filter natural solar radiation and simulate an environment of reduced UV-B for comparative purposes.Overall, the effectiveness of UV-B varies both among species and among cultivars of a given species. Sensitive plants often exhibit reduced growth (plant height, dry weight, leaf area, etc.), photosynthetic activity and flowering. Competitive interactions may also be altered indirectly by differential growth responses. Photosynthetic activity may be reduced by direct effects on photosynthetic enzymes, metabolic pathways or indirectly through effects on photosynthetic pigments or stomata1 function. The fluence response of these changes has yet to be clearly demonstrated in most cases. Plants sensitive to UV-B may also respond by accumulating UV-absorbing compounds in their outer tissue layers, which presumably protect sensitive targets from UV damage. Several key enzymes in the biosynthetic pathways of these compounds have been shown to be specifically induced by UV-B irradiation.Few studies have documented the effects of UV-B on total plant yield under field conditions. One notable exception is a 6-yr study with soybean demonstrating harvestable yield reductions under a simulated 25% ozone depletion. These effects are further modified by prevailing microclimatic conditions. Plants tend to be less sensitive to UV-B radiation under drought or mineral deficiency, while sensitivity increases under low levels of visible light. Further studies are needed to understand the mechanisms of UV-B effects and the interactions with present stresseb and future projected changes in the environment.

show abstract

“…S3; Blount et al, 2000;Hoffmann et al, 2006). The modulation of PAL activity by the metabolites of the phenylpropanoid pathway has already been reported and could cause the reduced level of the cinnamic acid derivative (Shirsat and Nair, 1986).…”

Section: Function Of Fagt1 In Plantamentioning

confidence: 99%

Redirection of Flavonoid Biosynthesis through the Down-Regulation of an Anthocyanidin Glucosyltransferase in Ripening Strawberry Fruit

et al. 2008

View full text Add to dashboard Cite

Strawberry (Fragaria 3 ananassa) fruit contains several anthocyanins that give the ripe fruits their attractive red color. The enzyme that catalyzes the formation of the first stable intermediate in the anthocyanin pathway is anthocyanidin-3-O-glucosyltransferase. A putative glycosyltransferase sequence (FaGT1) was cloned from a strawberry fruit cDNA library and the recombinant FaGT1 transferred UDP-glucose to anthocyanidins and, to a lesser extent, flavonols, generating the respective 3-O-glucosides. Quantitative polymerase chain reaction revealed that transcripts of FaGT1 were almost undetectable in green fruits, but gene expression increased dramatically in both turning and ripe red fruit, corresponding closely to the accumulation of anthocyanins during fruit ripening. The expression of FaGT1 is fruit associated and negatively regulated by auxin. To elucidate the in planta function of FaGT1, Agrobacterium tumefaciens cells harboring an intron-hairpin construct of a partial FaGT1 sequence were injected into midsized ripening fruits. In about one-third of the injected fruits, this led to significant down-regulation of FaGT1 transcript levels that corresponded to reduced concentrations of anthocyanin pigments in ripe strawberry fruits. In contrast, significant levels of epiafzelechin-formed by anthocyanidin reductase (ANR) from pelargonidin-were identified in FaGT1-silenced fruits, indicating competition of FaGT1 and FaANR for the common anthocyanidin substrate. Thus, FaGT1 represents an important branching-point enzyme because it is channeling the flavonoid pathway to anthocyanins. These results demonstrate a method to redirect the anthocyanin biosynthesis into flavan-3-ol production to increase the levels of bioactive natural products or modify pigments in plant tissues.

show abstract

The mode of inhibition of the biosynthesis of phenylalanine ammonia lyase by its product cinnamic acid in aging potato parenchyma tissue

Cited by 8 publications

References 26 publications

Phenylpropanoid Metabolism in Ripening Fruits

Phenylpropanoid Metabolism in Ripening Fruits

Uv‐b Effects on Terrestrial Plants

Redirection of Flavonoid Biosynthesis through the Down-Regulation of an Anthocyanidin Glucosyltransferase in Ripening Strawberry Fruit

Contact Info

Product

Resources

About