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In striking analogy with Saccharomyces cerevisiae, etiolated pea stem mitochondria did not show appreciable Ca2+ uptake. Only treatment with the ionophore ETH129 (which allows electrophoretic Ca2+ equilibration) caused Ca2+ uptake followed by increased inner membrane permeability, membrane depolarization and Ca2+ release. Like the permeability transition (PT) of mammals, yeast and Drosophila, the PT of pea stem mitochondria was stimulated by diamide and phenylarsine oxide and inhibited by Mg-ADP and Mg-ATP, suggesting a common underlying mechanism; yet, the plant PT also displayed distinctive features: (i) as in mammals it was desensitized by cyclosporin A, which does not affect the PT of yeast and Drosophila; (ii) similarly to S. cerevisiae and Drosophila it was inhibited by Pi, which stimulates the PT of mammals; (iii) like in mammals and Drosophila it was sensitized by benzodiazepine 423, which is ineffective in S. cerevisiae; (iv) like what observed in Drosophila it did not mediate swelling and cytochrome c release, which is instead seen in mammals and S. cerevisiae. We find that cyclophilin D, the mitochondrial receptor for cyclosporin A, is present in pea stem mitochondria. These results indicate that the plant PT has unique features and suggest that, as in Drosophila, it may provide pea stem mitochondria with a Ca2+ release channel.

Putative pea bilin and cyclic tetrapyrrole transporter proteins were identified by means of an antibody raised against a bilirubin-interacting aminoacidic sequence of mammalian bilitranslocase (TC No. 2.A.65.1.1). The immunochemical approach showed the presence of several proteins mostly in leaf microsomal, chloroplast and tonoplast vesicles. In these membrane fractions, electrogenic bromosulfalein transport activity was also monitored, being specifically inhibited by anti-bilitranslocase sequence antibody. Moreover, the inhibition of transport activity in pea leaf chloroplast vesicles, by both the synthetic cyclic tetrapyrrole chlorophyllin and the heme catabolite biliverdin, supports the involvement of some of these proteins in the transport of linear/cyclic tetrapyrroles during chlorophyll metabolism. Immunochemical localization in chloroplast sub-compartments revealed that these putative bilitranslocase-like transporters are restricted to the thylakoids only, suggesting their preferential implication in the uptake of cyclic tetrapyrrolic intermediates from the stroma during chlorophyll biosynthesis. Finally, the presence of a conserved bilin-binding sequence in different proteins (enzymes and transporters) from divergent species is discussed in an evolutionary context.

This paper aims at analysing the synthesis of flavonoids, their import and export in plant cell compartments, as well as their involvement in the response to stress, with particular reference to grapevine (Vitis vinifera L.). A multidrug and toxic compound extrusion (MATE) as well as ABC transporters have been demonstrated in the tonoplast of grape berry, where they perform a flavonoid transport. The involvement of a glutathione S-transferase (GST) gene has also been inferred. Recently, a putative flavonoid carrier, similar to mammalian bilitranslocase (BTL), has been identified in both grape berry skin and pulp. In skin the pattern of BTL expression increases from véraison to harvest, while in the pulp its expression reaches the maximum at the early ripening stage. Moreover, the presence of BTL in vascular bundles suggests its participation in long distance transport of flavonoids. In addition, the presence of a vesicular trafficking in plants responsible for flavonoid transport is discussed. Finally, the involvement of flavonoids in the response to stress is described.

The mitochondrial permeability transition (PT) is a well-recognized phenomenon that allows mitochondria to undergo a sudden increase of permeability to solutes with molecular mass ≤1500Da, leading to organelle swelling and structural modifications. The relevance of PT relies on its master role in the manifestation of programmed cell death (PCD). This function is performed by a mega-channel (in some cases inhibited by cyclosporin A) named permeability transition pore (PTP), whose function could derive from the assembly of different mitochondrial proteins.In this paper we examine the distribution and characteristics of PTP in mitochondria of eukaryotic organisms so far investigated in order to draw a hypothesis on the mechanism of its evolution. As a result, we suggest that PTP may have arisen as a new function linked to a multiple molecular exaptation of different mitochondrial proteins, even though they could nevertheless still play their original role.Furthermore, we suggest that the early appearance of PTP could have had a crucial role in the establishment of endosymbiosis in eukaryotic cells, by the coordinated balancing of ATP production by glycolysis (performed by the primary phagocyte) and oxidative phosphorylation (accomplished by the endosymbiont). Indeed, we argue on the possibility that this new energetic equilibrium could have opened the way to the subsequent evolution toward metazoans.

The synthesis of ATP in mitochondria is dependent on a low permeability of the inner membrane. Nevertheless, mitochondria can undergo an increased permeability to solutes, named permeability transition (PT) that is mediated by a permeability transition pore (PTP). PTP opening requires matrix Ca(2+) and leads to mitochondrial swelling and release of intramembrane space proteins (e.g., cytochrome c). This feature has been initially observed in mammalian mitochondria and tentatively attributed to some components present either in the outer or inner membrane. Recent works on mammalian mitochondria point to mitochondrial ATP synthase dimers as physical basis for PT, a finding that has been substantiated in yeast and Drosophila mitochondria. In plant mitochondria, swelling and release of proteins have been linked to programmed cell death, but in isolated mitochondria PT has been observed in only a few cases and in plant cell cultures only indirect evidence is available. The possibility that mitochondrial ATP synthase dimers could function as PTP also in plants is discussed here on the basis of the current evidence. Finally, a hypothetical explanation for the origin of PTP is provided in the framework of molecular exaptation.

Iron sequestration inside the plant cell may be accomplished by ferritins, a class of proteins able to buffer and store this metal in a safe and soluble form. This protein has been shown in plastids and only recently in plant mitochondria. In this paper, we examined the localization of mitochondrial ferritin in different plant organs and its possible involvement in iron uptake and/or release. Ferritin was found only in mitochondria from young organs, such as roots, etiolated stems and, although to a lesser extent, developing leaves. Its presence was not influenced by iron in the hydroponic medium of culture, as well as by the induction of senescence through ethylene treatment. Lipoperoxidation, evaluated as formation of thiobarbituric acid reactive substances (TBARS), was determined in mitochondria isolated from etiolated stems and leaves of plants incubated with FeSO 4 /citrate and ascorbate. The phenomenon was lower in young stem mitochondria, where ferritin was detected, than in those from leaves, where the protein was undetectable. Therefore, these results indicate that the mitochondrial ferritin was able to sequestrate iron within its shell. A significant increase of TBARS formation was also found in etiolated stem mitochondria incubated, in the absence of supplied iron, with 5 mM ascorbate, which was paralleled by a decrease of iron in mitochondrial ferritin, detected by Inductively Coupled Plasma Mass Spectrum (ICP-MS) measurements after immunoprecipitation. These results indicate that plant mitochondrial ferritin plays a key role in iron buffering through the uptake and release of iron that could be modulated by ascorbate.

Bilitranslocase is a rat liver plasma membrane carrier, displaying a high-affinity binding site for bilirubin. It is competitively inhibited by grape anthocyanins, including aglycones and their mono- and di-glycosylated derivatives. In plant cells, anthocyanins are synthesized in the cytoplasm and then translocated into the central vacuole, by mechanisms yet to be fully characterized. The aim of this work was to determine whether a homologue of rat liver bilitranslocase is expressed in carnation petals, where it might play a role in the membrane transport of anthocyanins. The bromosulfophthalein-based assay of rat liver bilitranslocase transport activity was implemented in subcellular membrane fractions, leading to the identification of a bromosulfophthalein carrier (K(M) = 5.3 microm), which is competitively inhibited by cyanidine 3-glucoside (Ki = 51.6 microm) and mainly noncompetitively by cyanidin (Ki = 88.3 microm). Two antisequence antibodies against bilitranslocase inhibited this carrier. In analogy to liver bilitranslocase, one antibody identified a bilirubin-binding site (Kd = 1.7 nm) in the carnation carrier. The other antibody identified a high-affinity binding site for cyanidine 3-glucoside (Kd = 1.7 microm) on the carnation carrier only, and a high-affinity bilirubin-binding site (Kd = 0.33 nm) on the liver carrier only. Immunoblots showed a putative homologue of rat liver bilitranslocase in both plasma membrane and tonoplast fractions, isolated from carnation petals. Furthermore, only epidermal cells were immunolabeled in petal sections examined by microscopy. In conclusion, carnation petals express a homologue of rat liver bilitranslocase, with a putative function in the membrane transport of secondary metabolites.

In this work, evidence for the presence of ferritins in plant mitochondria is supplied. Mitochondria were isolated from etiolated pea stems and Arabidopsis thaliana cell cultures. The proteins were separated by SDS/PAGE. A protein, with an apparent molecular mass of approximately 25-26 kDa (corresponding to that of ferritin), was cross-reacted with an antibody raised against pea seed ferritin. The mitochondrial ferritin from pea stems was also purified by immunoprecipitation. The purified protein was analyzed by MALDI-TOF mass spectrometry and the results of both mass finger print and peptide fragmentation by post source decay assign the polypeptide sequence to the pea ferritin (P < 0.05). The mitochondrial localization of ferritin was also confirmed by immunocytochemistry experiments on isolated mitochondria and cross-sections of pea stem cells. The possible role of ferritin in oxidative stress of plant mitochondria is discussed.

A soluble protein with a molecular mass of 55 kDa has been purified from etiolated pea stem mitochondria. The protein exhibits a Mg2+-requiring PPiase activity, with an optimum at pH 9.0, which is not stimulated by monovalent cations, but inhibited by F−, Ca2+, aminomethylenediphosphate and imidodiphosphate. The protein does not cross-react with polyclonal antibodies raised against vacuolar, mitochondrial or soluble PPiases, respectively. Conversely, it cross-reacts with an antibody for the α/β-subunit of the ATP synthase from beef heart mitochondria. The purified protein has been analyzed by MALDI-TOF mass spectrometry and the results, covering the 30% of assigned sequence, indicate that it corresponds to the β-subunit of the ATP synthase of pea mitochondria. It is suggested that this enzymatic protein may perform a dual function as soluble PPiase or as subunit of the more complex ATP synthase.

In this paper, lipase activity was characterized in coffee (Coffea arabica L.) seeds to determine its involvement in lipid degradation during germination. The lipase activity, evaluated by a colorimetric method, was already present before imbibition of seeds and was further induced during the germination process. The activity showed a biphasic behaviour, which was similar in seeds either with or without endocarp (parchment), even though the phenomenon showed a delay in the former. The enzymatic activity was inhibited by tetrahydrolipstatin (THL), a selective and irreversible inhibitor of lipases, and by a polyclonal antibody raised against purified alkaline lipase from castor bean. The immunochemical analysis evidenced a protein of ca. 60 kDa, cross-reacting with an anti-lipase antibody, in coffee samples obtained from seeds of both types. Gas chromatographic analyses of free fatty acid (FFA) content confirmed the differences shown in the lipolytic activity of the samples with or without parchment, since FFA levels increased more rapidly in samples without parchment. Finally, the analyses of the antioxidant capacity showed that the presence of parchment was crucial for lowering the oxidation of the lipophylic fraction, being the seeds with parchment less prone to oxidation processes.

The influence of light on fresh-cut vegetables during storage is controversial, since both positive and negative effects on shelf-life and quality of such products have been observed. In this work, the effect of low-intensity light treatments on lamb's lettuce, a fresh-cut leafy and ready-to-eat vegetable, was investigated during storage at low temperature (6 °C), in comparison with conventional storage (in the dark at 4 °C). Although continuous light treatment (1 cycle of 8 h per day) was deleterious, cycles of light treatments (8 cycles of 1 h per day; 16 cycles of 0.5 h per day) showed positive effects, assessed by evaluating the content of chlorophylls, carotenoids, ATP, glucose and ascorbate. These analyses were performed at the beginning and after 6 days of storage, in comparison with samples stored in the dark at 4 °C. Under low-intensity light treatments, even if performed at a higher temperature (6 °C), the content of such bioactive compounds increased or was at least similar to that found in samples stored in the dark at the same temperature. We suggest that continuous low-intensity light treatments during cold storage of lamb's lettuce are able to promote photosynthesis but, at the same time, induce photo-damage. On the contrary, under intermittent low-intensity light cycles, photosynthesis is only partially activated, while the metabolism of the green tissues is still able to provide carbon moieties for the synthesis of bioactive molecules involved in delaying senescence. Therefore, low-intensity light cycles at 6 °C could contribute to maintain quality of lamb's lettuce, with respect to samples stored in the dark at both 6 and 4 °C. Finally, setting the temperature at 6 °C allows reduction of refrigerator energy consumption during storage.

Flavonoids are a class of secondary metabolites present in large amounts in grapevine (Vitis vinifera L.), which are involved in several aspects of its physiology (e.g. protection against biotic and abiotic stress). Even if the biosynthetic pathways of flavonoid sub-classes have been largely characterised, the mechanisms of their transport and accumulation to the final target sites are still not completely understood. Unanticipated insights have been obtained by probing plant tissues with pure antibodies targeting bilitranslocase (BTL, TCDB # 2.A.65.1.1), a mammalian transporter involved in the absorption and tissue distribution of dietary flavonoids. The occurrence of a BTL homologue has also been found in grape berries, in both tegumental layers of skin and pulp vascular bundles. In the skin, the expression of this protein starts from véraison (starting of the change in colour and softening of berries) and increases up to a maximum at the harvest stage, matching the same temporal pattern of flavonoid accumulation.

Flavonoids are a class of secondary metabolites present in large amounts in grapevine (Vitis vinifera L.), which are involved in several aspects of its physiology (e.g. protection against biotic and abiotic stress). Even if the biosynthetic pathways of flavonoid sub-classes have been largely characterised, the mechanisms of their transport and accumulation to the final target sites are still not completely understood. Unanticipated insights have been obtained by probing plant tissues with pure antibodies targeting bilitranslocase (BTL, TCDB # 2.A.65.1.1), a mammalian transporter involved in the absorption and tissue distribution of dietary flavonoids. The occurrence of a BTL homologue has also been found in grape berries, in both tegumental layers of skin and pulp vascular bundles. In the skin, the expression of this protein starts from veraison (starting of the change in colour and softening of berries) and increases up to a maximum at the harvest stage, matching the same temporal pattern of flavonoid accumulation.

Practical applications: In this paper we studied the lipoxygenase (LOX) and hydroperoxide lyase (HPL) activities, and the formation of their products (hydroperoxides and aldehydes) in microsomes extracted from olive pulp of two Italian cultivars. The study of LOX and HPL, belonging to the so-called ‘oxylipin pathway’, has important implications on the aroma development in both fruit and oil. Thus, a better knowledge of the properties of these enzymes can be useful to improve the organoleptic features of the oil. In fact, ‘LOX pathway’ may play a positive role in the formation of pleasant flavours during the technological processes. The preliminary study of the activity of the LOX/HPL enzymes could represent an important tool to facilitate the varietal choice in order to improve oil quality.

During maturation, Vitis vinifera berries accumulate a large amount of several anthocyanins in the epidermal tissue, whereas their precursors and intermediates are ubiquitously synthesized within the fruit. Up to date, several mechanisms of flavonoid transport at subcellular level have been hypothesized, but it is not possible to identify a general model applicable in every plant tissue and organ. Recently, a putative anthocyanin carrier, homologue to mammalian bilitranslocase (BTL) (TC 2.A.65.1.1), was found in Dianthus caryophyllus petal microsomes. In the present paper, an immunohistochemical and immunochemical analysis, using an antibody raised against a BTL epitope, evidences the expression and function of such a transporter in V. vinifera berries (cv. Merlot). Specific localisations of the putative carrier within berry tissues together with expression changes during different developmental stages are shown. Water stress induces an increase in protein expression in both skin and pulp samples. A bromosulfalein (BSP) uptake activity, inhibitable by the BTL antibody, is detected in berry mesocarp microsomes, with K m = 2.39 μM BSP and V max = 0.29 μmol BSP min−1 mg−1 protein. This BSP uptake is also competitively inhibited by quercetin (K i = 4 μM). A putative role for this carrier is discussed in relation to the membrane transport of secondary metabolites.

Summary This report demonstrates that mitochondria isolated from thermogenic Arum spadices possess an ATP-sensitive potassium channel – responsible for electrical potential (ΔΨ) collapse and mitochondrial swelling – whose characteristics are similar to those previously described in pea and wheat mitochondria. In order to study the relationship between this K ATP + channel and the uncoupled respiration, linked to thermogenesis, K+ transport activities were compared with those of mitochondria that were isolated from pea stems, soybean suspension cell cultures and Arum tubers. The channel from Arum spadices is highly active and its major features are (i) potassium flux is performed primarily in an inward-rectifying manner; (ii) the influx of K+ is associated with a matrix volume increase in both energized and non-energized mitochondria; and (iii) its activity depends on the redox state of electron transport chain (ETC) and oxygen availability. In particular, this paper shows that the K ATP + channel is inwardly activated in parallel with the alternative oxidase (AO). The activation is linked to an ETC-oxidized state and to high oxygen consumption. The putative role of this K ATP + channel is discussed in relation to flowering of thermogenic Arum spadices.

Programmed cell death (PCD) is a finely tuned process of multicellular organisms. In higher plants, PCD regulates many developmental processes and the response of host plants to incompatible pathogens (hypersensitive response). Four types of PCD have been described in plants, mainly associated to vacuole rupture, that is followed by the appearance of the typical PCD hallmarks (i.e. nuclear DNA fragmentation and cell shrinkage). However, in some cases vacuole collapse is preceded by an early alteration of other subcellular organelles, such as mitochondria. In particular, the central role played by mitochondria in PCD has been largely recognised in animal cells. This review deals with the involvement of mitochondria in the manifestation of plant PCD, in n comparison to that described in animal PCD. The main hallmark, connecting animal and plant PCD via mitochondria, is represented by the release of cytochrome c and possibly other chemicals such as nucleases, which may be accomplished by different mechanisms, involving both swelling and non-swelling of the organelles.

In this paper lipoxygenase (LOX) presence was investigated in coffee berries to determine its involvement in lipid degradative metabolism of plants grown in organic and conventional cultivations. An immunochemical analysis has evidenced a ca. 80 kDa protein, cross-reacting with an anti-LOX antibody, only in the pulp fraction of berries obtained from plants of both cultivations. LOX activity in this fraction could be monitored either as conjugated diene formation or reaction products (determined by HPLC) and was mainly associated with a heavy membrane fraction (HMF, enriched in tonoplast, endoplasmic reticulum, plasma membrane, and mitochondria) and a light membrane fraction (LMF, enriched in plasma membrane and endoplasmic reticulum, with low levels of tonoplast and mitochondria). The LOX activity of LMF from berries of both cultivations showed an optimum at pH 8.0. The HMF exhibited a different activity peak in samples from conventional (pH 8.0) and organic (pH 5.5) cultures, suggesting the presence of different isoenzymes. These findings were also confirmed by variation of the ratio of 9- and 13-hydroperoxides in organic (1:1) and conventional cultivations (1:10), indicating that the organic one was subjected to an oxidative stress in the coffee pulp fraction leading to the expression of an acidic LOX. Such de novo synthesized LOX activity could be responsible for the production of secondary metabolites, which may interfere with the organoleptic profile of coffee.

Bilitranslocase is a rat liver plasma membrane carrier, displaying a high-affinity binding site for bilirubin. It is competitively inhibited by grape anthocyanins, including aglycones and their mono- and di-glycosylated derivatives. In plant cells, anthocyanins are synthesized in the cytoplasm and then translocated into the central vacuole, by mechanisms yet to be fully characterized. The aim of this work was to determine whether a homologue of rat liver bilitranslocase is expressed in carnation petals, where it might play a role in the membrane transport of anthocyanins. The bromosulfophthalein-based assay of rat liver bilitranslocase transport activity was implemented in subcellular membrane fractions, leading to the identification of a bromosulfophthalein carrier (K(M) = 5.3 microm), which is competitively inhibited by cyanidine 3-glucoside (Ki = 51.6 microm) and mainly noncompetitively by cyanidin (Ki = 88.3 microm). Two antisequence antibodies against bilitranslocase inhibited this carrier. In analogy to liver bilitranslocase, one antibody identified a bilirubin-binding site (Kd = 1.7 nm) in the carnation carrier. The other antibody identified a high-affinity binding site for cyanidine 3-glucoside (Kd = 1.7 microm) on the carnation carrier only, and a high-affinity bilirubin-binding site (Kd = 0.33 nm) on the liver carrier only. Immunoblots showed a putative homologue of rat liver bilitranslocase in both plasma membrane and tonoplast fractions, isolated from carnation petals. Furthermore, only epidermal cells were immunolabeled in petal sections examined by microscopy. In conclusion, carnation petals express a homologue of rat liver bilitranslocase, with a putative function in the membrane transport of secondary metabolites.

In this work, evidence for the presence of ferritins in plant mitochondria is supplied. Mitochondria were isolated from etiolated pea stems and Arabidopsis thaliana cell cultures. The proteins were separated by SDS/PAGE. A protein, with an apparent molecular mass of approximately 25-26 kDa (corresponding to that of ferritin), was cross-reacted with an antibody raised against pea seed ferritin. The mitochondrial ferritin from pea stems was also purified by immunoprecipitation. The purified protein was analyzed by MALDI-TOF mass spectrometry and the results of both mass finger print and peptide fragmentation by post source decay assign the polypeptide sequence to the pea ferritin (P0.05). The mitochondrial localization of ferritin was also confirmed by immunocytochemistry experiments on isolated mitochondria and cross-sections of pea stem cells. The possible role of ferritin in oxidative stress of plant mitochondria is discussed.

Pea (Pisum sativum) stem mitochondria, energized by NADH, succinate or malate plus glutamate, underwent a spontaneous low-amplitude permeability transition (PT), which could be monitored by dissipation of the electrical potential (deltapsi) or swelling. The occurrence of the latter effects was dependent on O2 availability, because O2 shortage anticipated the manifestation of both deltapsi dissipation and swelling. Spontaneous deltapsi collapse was also monitored in sucrose-resuspended mitochondria and again O2 deprivation caused an anticipation of the phenomenon. However, in this case deltapsi dissipation was not accompanied by a parallel mitochondrial swelling. The latter effect was, indeed, evident only if mitochondria were resuspended in KCl (as osmoticum), or other cations with a molecular mass up to 100 Da (choline+). PT was also induced by protonophores (carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) or free fatty acids) or valinomycin (only in KCl). The FCCP-induced dissipation of deltapsi and swelling were inhibited by ATP and stimulated (anticipated) by cyclosporin A or O2 shortage. The FCCP-induced PT was accompanied by the release of pyridine nucleotides from the matrix and of cytochrome c from the intermembrane space of KCl-resuspended mitochondria. The spontaneous and FCCP-induced low-amplitude PT of plant mitochondria are interpreted as due to the activity of a recently identified K(ATP)+ channel whose open/closed state is dependent on polarization of the inner membrane and on the oxidoreductive state of some sulfhydryl groups.

Background Senescence is a key developmental process occurring during the life cycle of plants that can be induced also by environmental conditions, such as starvation and/or darkness. During senescence, strict control of genes regulates ordered degradation and dismantling events, the most remarkable of which are genetically programmed cell death (PCD) and, in most cases, an upregulation of flavonoid biosynthesis in the presence of light. Flavonoids are secondary metabolites that play multiple essential roles in development, reproduction and defence of plants, partly due to their well-known antioxidant properties, which could affect also the same cell death machinery. To understand further the effect of endogenously-produced flavonoids and their interplay with different environment (light or dark) conditions, two portions (red and green) of a senescing grapevine callus were used to obtain suspension cell cultures. Red Suspension cell Cultures (RSC) and Green Suspension cell Cultures (GSC) were finally grown under either dark or light conditions for 6 days. Results Darkness enhanced cell death (mainly necrosis) in suspension cell culture, when compared to those grown under light condition. Furthermore, RSC with high flavonoid content showed a higher viability compared to GSC and were more protected toward PCD, in accordance to their high content in flavonoids, which might quench ROS, thus limiting the relative signalling cascade. Conversely, PCD was mainly occurring in GSC and further increased by light, as it was shown by cytochrome c release and TUNEL assays. Conclusions Endogenous flavonoids were shown to be good candidates for exploiting an efficient protection against oxidative stress and PCD induction. Light seemed to be an important environmental factor able to induce PCD, especially in GSC, which lacking of flavonoids were not capable of preventing oxidative damage and signalling leading to senescence. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0917-y) contains supplementary material, which is available to authorized users.

Flavonoids are a group of secondary metabolites widely distributed in plants that represent a huge portion of the soluble phenolics present in grapevine (Vitis vinifera L.). These compounds play different physiological roles and are often involved in protection against biotic and abiotic stress. Even if the flavonoid biosynthetic pathways have been largely characterized, the mechanisms of their transport and accumulation in cell wall and vacuole are still not completely understood. This review analyses the known mechanisms of flavonoid uptake and accumulation in grapevine, with reference to the transport models and membrane carrier proteins described in other plant species. The effect of different environmental factors on flavonoid biosynthesis and transporters is also discussed.