Xue-Ren Yin

Zhejiang University, Hang-hsien, Zhejiang Sheng, China

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Publications (27)84.29 Total impact

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    ABSTRACT: Organic acids are essential to fruit flavor. The vacuolar H+ transporting adenosine triphosphatase (V-ATPase) plays an important role in organic acid transport and accumulation. However, less is known of V-ATPase interacting proteins and their relationship with organic acid accumulation. The relationship between V-ATPase and citric acid was investigated, using the citrus tangerine varieties ‘Ordinary Ponkan (OPK)’ and an early maturing mutant ‘Zaoshu Ponkan (ZPK)’. Five V-ATPase genes (CitVHA) were predicted as important to citric acid accumulation. Among the genes, CitVHA-c4 was observed, using a yeast two-hybrid screen, to interact at the protein level with an ethylene response factor, CitERF13. This was verified using bimolecular fluorescence complementation assays. A similar interaction was also observed between Arabidopsis AtERF017 (a CitERF13 homolog) and AtVHA-c4 (a CitVHA-c4 homolog). A synergistic effect on citric acid levels was observed between V-ATPase proteins and interacting ERFs when analyzed using transient over-expression in tobacco and Arabidopsis mutants. Furthermore, the transcript abundance of CitERF13 was concomitant with CitVHA-c4. CitERF13 or AtERF017 over-expression leads to significant citric acid accumulation. This accumulation was abolished in an AtVHA-c4 mutant background. ERF-VHA interactions appear to be involved in citric acid accumulation, which was observed in both citrus and Arabidopsis.
    No preview · Article · Feb 2016 · Scientific Reports
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    ABSTRACT: Ethylene is one of the most important plant hormones regulating fruit ripening. In kiwifruit, 14 AdERF genes have been reported, and some members were reported to be involved in fruit ripening and softening. However, a genome-wide investigation of the kiwifruit ERF family was not carried out. Here, 105 novel ERF genes were obtained from the kiwifruit genome. Phylogenetic and MEME analyses indicated that kiwifruit ERF genes are distributed in different subfamilies and all have single AP2/ERF domain. Moreover, some ERF members were putative repressors, as indicated by the presence of EAR motifs. The relationship between the ERF family and kiwifruit ripening we investigated with C2H4 treatment and CA storage. Gene expression analyses pointed out eight ripening related ERF genes, including four putative activators (AdERF10/14/15/75) and four putative repressors (AdERF7/8/19/21) of ripening.
    No preview · Article · Feb 2016 · Scientia Horticulturae
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    ABSTRACT: Postharvest deastringency is important for persimmon fruit, since most cultivars are of the astringent type. In the present research, astringency as indicated by the decrease in soluble tannin content, was removed from 'Mopan' persimmon by placing them in an atmosphere of 95% CO2. In contrast to the decrease in soluble tannin, increases in concentrations of acetaldehyde and ethanol were transiently triggered by CO2 treatment. Four DkMYB genes, DkMYB5-8, belonging to the R2R3 MYB family, were isolated. mRNA accumulation studies indicated that DkMYB5-8 were up-regulated by CO2 treatment, and that expression was positively correlated with persimmon fruit astringency removal. However, using a dual-luciferase assay, only one of these four DkMYB genes, DkMYB6, showed the ability to trans-activate the promoters of the previously identified persimmon fruit deastringency-related genes DkPDC2 and DkPDC3. Furthermore, DkMYB6 were also observed to be an activator of the previously characterized deastringency regulators, DkERF9 and DkERF19. Thus, DkMYB6 is a putative transcriptional activator, induced by high CO2, which is involved in persimmon fruit deastringency, by operating on both DkPDC structural genes and DkERF transcription factors.
    No preview · Article · Jan 2016 · Postharvest Biology and Technology
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    ABSTRACT: Chrysanthemums (Chrysanthemum morifolium Ramat.) exhibit a variety of flower colors due to their differing abilities to accumulate anthocyanins. One MYB member, CmMYB6, has been verified as a transcription regulator of chrysanthemum genes involved in anthocyanin biosynthesis; however, the co-regulators for CmMYB6 remain unclear in chrysanthemum. Here, the expression pattern of CmbHLH2, which is clustered in the IIIf bHLH subgroup, was shown to be positively correlated with the anthocyanin content of cultivars with red, pink and yellow flower colors, respectively. CmbHLH2 significantly upregulated the CmDFR promoter and triggered anthocyanin accumulation when co-expressed with CmMYB6. Yeast one-hybrid analyses indicated that CmbHLH2 was able to bind directly to the CmDFR promoter. Moreover, yeast two-hybrid assays indicated protein-protein interaction between CmbHLH2 and CmMYB6. These results suggest that CmbHLH2 is the essential partner for CmMYB6 in regulating anthocyanin biosynthesis in chrysanthemum.
    Preview · Article · Nov 2015 · PLoS ONE
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    ABSTRACT: Organic acids strongly influence the organoleptic properties of fruit, and in citrus the major organic acid is citric acid. The pH-associated genes (PH) have been widely studied in various fruit and their expression has been suggested to be linked to citric acid accumulation in citrus fruit, but in planta functional evidence is lacking. A novel PH-like gene, named CrMYB73, was isolated from ‘Ponkan’ (Citrus reticulate Blanco) fruit, and the amino acid sequence analysis suggested that CrMYB73 was an R2R3 MYB protein. Expression of CrMYB73 was positively correlated with citric acid accumulation and its role was tested directly by overexpression in both wild type and anthocyanin-enriched transgenic Nicotiana tabacum. The results indicated that transient overexpression of CrMYB73 leads to citric acid accumulation.
    No preview · Article · Oct 2015 · Scientia Horticulturae
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    ABSTRACT: Metabolism of anthocyanin in Chrysanthemum (Chrysanthemum morifolium Ramat.) is catalyzed by several biosynthetic enzymes, however, the underlying transcriptional regulatory mechanisms remain unknown. In the present research, four MYB transcription factors, CmMYB3-6, were isolated from 'Amadea' Chrysanthemum, by RNA-seq and RACE. Among the four CmMYBs, CmMYB3 and CmMYB6 were expressed concurrently with the expression of biosynthetic genes and accumulation of anthocyanin during flower development. In order to study the transcription regulatory role of CmMYB3 and CmMYB6 in anthocyanin biosynthesis, the promoter region of CmDFR was isolated. Dual luciferase assay showed that CmMYB6 significantly activated the CmDFR promoter more than 8-fold. Furthermore, the combination of CmMYB6 and MrbHLH1 (from Myrica rubra involved in anthocyanin biosynthesis) resulted in approximately 34-fold induction of the CmDFR promoter. Using a transient over-expression system in Nicotiana tabacum leaves, CmMYB6 and MrbHLH1 co-expression lead to transient anthocyanin accumulation. Thus, CmMYB6 is proposed as a novel transcription factor in Chrysanthemum anthocyanin biosynthesis.
    No preview · Article · Oct 2015 · Scientia Horticulturae
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    ABSTRACT: Lignin biosynthesis is regulated by many transcription factors, such as those of the MYB and NAC families. However, the roles of AP2/ERF transcription factors in lignin biosynthesis have been rarely investigated. Eighteen EjAP2/ERF genes were isolated from loquat fruit (Eriobotrya japonica), which undergoes postharvest lignification during low temperature storage. Among these, expression of EjAP2-1, a transcriptional repressor, was negatively correlated with fruit lignification. The dual-luciferase assay indicated that EjAP2-1 could trans-repress activities of promoters of lignin biosynthesis genes from both Arabidopsis and loquat. However, EjAP2-1 did not interact with the target promoters (Ej4CL1). Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays indicated protein-protein interactions between EjAP2-1 and lignin biosynthesis-related EjMYB1 and EjMYB2. Furthermore, repression effects on the Ej4CL1 promoter were observed with the combination of EjAP2-1 and EjMYB1 or EjMYB2, while EjAP2-1 with the EAR motif mutated (mEjAP2-1) lost such repression, although mEjAP2-1 still interacted with EjMYB protein. Based on these results, it is proposed that EjAP2-1 is an indirect transcriptional repressor on lignin biosynthesis, and the repression effects were manifested by EAR motifs and were conducted via protein-protein interaction with EjMYBs. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.
    No preview · Article · Mar 2015 · Plant Biotechnology Journal
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    ABSTRACT: NAC genes have been characterized in numerous plants, where they are involved in responses to biotic and abiotic stress, including low oxygen stress. High concentration of CO2 is one of the most effective treatments to remove astringency of persimmon fruit owing to the action of the accumulated anoxia metabolite acetaldehyde. In model plants, NAC genes have been identified as being responsive to low oxygen. However, the possible relationship between NAC transcription factors and persimmon astringency removal remains unexplored. In the present research, treatment with a high concentration of CO2 (95%) effectively removed astringency of "Mopan" persimmon fruit by causing decreases in soluble tannin. Acetaldehyde content increased in response to CO2 treatment concomitantly with astringency removal. Using RNA-seq and Rapid amplification of cDNA ends (RACE), six DkNAC genes were isolated and studied. Transcriptional analysis indicated DkNAC genes responded differentially to CO2 treatment; DkNAC1, DkNAC3, DkNAC5 and DkNAC6 were transiently up-regulated, DkNAC2 was abundantly expressed 3 days after treatment, while the DkNAC4 was suppressed during astringency removal. It is proposed that DkNAC1/3/5/6 could be important candidates as regulators of persimmon astringency removal and the roles of other member are also discussed.
    Full-text · Article · Jan 2015 · International Journal of Molecular Sciences
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    ABSTRACT: Bagging is a useful method to improve fruit quality by altering its exposure to light, whereas its effect on fruit volatiles production is inconsistent, and the genes responsible for the observed changes remain unknown. In the present study, single-layer yellow paper bags were used to study the effects of bagging treatment on the formation of C6 aldehydes in peach fruit (Prunus persica L. Batsch, cv. Yulu) over two succeeding seasons. Higher concentrations of n-hexanal and (E)-2-hexenal, which are characteristic aroma volatiles of peach fruit, were induced by bagging treatment. After bagging treatment, peach fruit had significantly higher LOX and HPL enzyme activities, accompanying increased contents of C6 aldehydes. The gene expression data obtained through real-time PCR showed that no consistent significant differences in transcript levels of LOX genes were observed over the two seasons, but significantly up-regulated expression was found for PpHPL1 after bagging treatment In addition, bagging-treated fruit produced more (E)-2-hexenal and had higher expression levels of PpHPL1 during postharvest ripening at room temperature. The regulatory role of the LOX-HPL pathway on the biosynthesis of n-hexanal and (E)-2-hexenal in response to bagging treatment during peach fruit development is discussed in the text.
    Preview · Article · Sep 2014 · Molecules
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    ABSTRACT: Lignin biosynthesis and its transcriptional regulatory networks have been studied in model plants and woody trees. However, lignification also occurs in some fleshy fruit and has rarely been considered in this way. Loquat ( Eriobotrya japonica ) is one such convenient tissue for exploring the transcription factors involved in regulating fruit flesh lignification. Firmness and lignin content of ‘Luoyangqing’ loquat were fund to increase during low-temperature storage as a typical symptom of chilling injury, while heat treatment (HT) and low-temperature conditioning (LTC) effectively alleviated them. Two novel EjMYB genes, EjMYB1 and EjMYB2, were isolated and were found to be localized in the nucleus. These genes responded differently to low temperature, with EjMYB1 induced and EjMYB2 inhibited at 0 °C. They also showed different temperature responses under HT and LTC conditions, and may be responsible for different regulation of flesh lignification at the transcriptional level. Transactivation assays indicated that EjMYB1 and EjMYB2 are a transcriptional activator and repressor, respectively. EjMYB1 activated promoters of both Arabidopsis and loquat lignin biosynthesis genes, while EjMYB2 countered the inductive effects of EjMYB1. This finding was also supported by transient overexpression in tobacco. Regulation of lignification by EjMYB1 and EjMYB2 is likely to be achieved via their competitive interaction with AC elements in the promoter region of lignin biosynthesis genes such as Ej4CL1.
    Preview · Article · May 2014 · Journal of Experimental Botany
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    ABSTRACT: A hypoxic environment is generally undesirable for most plants and stimulates anaerobic metabolism. It is a beneficial treatment, however, for the removal of astringency from persimmon to improve the fruit quality after harvest. High soluble tannins (SCTs) content is one of most important causes of astringency. High CO2 (95%) treatment effectively reduced SCTs in both "Mopan" and "Gongcheng-shuishi" persimmon fruit by causing increases in acetaldehyde. Using RNA-seq and realtime PCR, twelve ethylene response factor genes (DkERF11-22) were isolated and characterized, to determine those responsive to high CO2 treatment. Only two genes, DkERF19 and DkERF22, showed trans-activation effects on the promoters of deastringency-related genes pyruvate decarboxylase genes (DkPDC2 and DkPDC3) and the transcript levels of these genes was enhanced by hypoxia. Moreover, DkERF19 and the previously isolated DkERF9 had additive effects on activating the DkPDC2 promoter. Taken together, these results provide further evidence that transcriptome changes in the level of DkERF mRNAs regulate deastringency-related genes and their role in the mechanism of persimmon fruit deastringency is discussed.
    Full-text · Article · May 2014 · PLoS ONE
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    ABSTRACT: The AP2/ERF gene family encodes plant-specific transcription factors. In model plants, AP2/ERF genes have been shown to be expressed in response to developmental and environmental stimuli, and many function downstream of the ethylene, biotic, and abiotic stress signaling pathways. In citrus, ethylene is effective in regulation citrus fruit quality, such as degreening and aroma. However, information about the citrus AP2/ERF family is limited, and would enhance our understanding of fruit responses to environmental stress, fruit development and quality. CitAP2/ERF genes were isolated using the citrus genome database, and their expression patterns analyzed by real-time PCR using various orange organs and samples from a fruit developmental series. 126 sequences with homologies to AP2/ERF proteins were identified from the citrus genome, and, on the basis of their structure and sequence, assigned to the ERF family (102), AP2 family (18), RAV family (4) and Soloist (2). MEME motif analysis predicted the defining AP2/ERF domain and EAR repressor domains. Analysis of transcript accumulation in Citrus sinensis cv. 'Newhall' indicated that CitAP2/ERF genes show organ-specific and temporal expression, and provided a framework for understanding the transcriptional regulatory roles of AP2/ERF gene family members in citrus. Hierarchical cluster analysis and t tests identified regulators that potentially function during orange fruit growth and development.
    No preview · Article · Feb 2014 · Molecular Biology Reports
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    ABSTRACT: Peach fruits are sensitive to chilling injury (CI) during postharvest cold storage and their subsequent shelf-life, which results in loss of quality and market value. Many studies have examined the development of CI, including analyses of changes in biochemical composition, enzyme activity and gene expression; however, the molecular mechanism of CI remains unresolved. Six C-repeat (CRT) / dehydration-responsive element (DRE) binding factor (CBF) genes (PpCBF1-6) were isolated and characterized in peach fruit based on their homology to CBF genes that are available in public Prunus persica genome databases. The expression patterns of these genes were analyzed in response to varying temperatures and durations of treatment. Transcription of PpCBF1/5/6 was induced at low temperatures, whereas expression of other CBF genes remained relatively constant. The results presented here indicate that treating peach fruit with a CI-delaying temperature (0 °C) resulted in a greater accumulation of PpCBF1/5/6 transcripts than that observed in fruit treated with a CI-inducing temperature (5 °C). CBF gene induction was accompanied by a decrease in CI symptoms, including a loss of firmness, flesh browning and increased electrical conductivity, throughout the experimental 21-day cold storage period. An analysis of the upstream nucleotide sequence of CBF genes showed that a cis element inducer of CBF expression 1 (ICEr1) was detected in the promoter of PpCBF1/5/6.
    Full-text · Article · Dec 2013 · Plant Molecular Biology Reporter
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    ABSTRACT: Anthocyanins, being important for both plant functions and human health, were transcriptionally regulated by the MYB–bHLH–WD40 transcription complex. The key MYB regulator for Chinese bayberry (Myrica rubra), MrMYB1, has been characterized in previous studies, while the specific bHLH partner(s) are unknown. In this study, MrbHLH1 and MrbHLH2 were isolated based on their homology to known plant bHLHs involved in anthocyanin biosynthesis regulation. Coordinate expression of MrbHLH1 with MrMYB1 and the anthocyanin biosynthetic genes was observed during fruit development, while MrbHLH2 showed a weaker correlation. Further transient assays in tobacco leaves suggested that MrbHLH1, but not MrbHLH2, was associated with MrMYB1 and triggered significant anthocyanin production. The lack of function of the MrbHLH2 in anthocyanin biosynthesis regulation suggested that different MrbHLH genes within the same phylogenic subfamily have different functions. Overexpression of MrMYB1 and MrbHLH1 in tobacco confirmed the crucial role of MrMYB1–MrbHLH1 in anthocyanin biosynthesis and all of the structural genes from NtCHS were up-regulated by the complex. Dual luciferase assays, however, indicated that MrMYB1 and MrbHLH1 selectively activated five of the eight promoters of biosynthetic genes from bayberry (MrCHI, MrF3′H, MrDFR1, MrANS, MrUFGT), although expression levels of all eight biosynthetic genes including MrCHS and downstream genes were coordinately increased during fruit ripening. Moreover, the interaction between MrbHLH1 and MrMYB1 was confirmed by yeast two-hybrid assay. In conclusion, MrbHLH1, but not MrbHLH2, was the essential partner of MrMYB1 during anthocyanin biosynthesis regulation in tobacco and bayberry, however, the biosynthetic genes in these two species responded differently to the MrMYB1–MrbHLH1 complex.
    Full-text · Article · Dec 2013 · Plant Cell Tissue and Organ Culture
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    ABSTRACT: Codon usage analysis has been a classical topic for decades and has significances for studies of evolution, mRNA translation, and new gene discovery, etc. While the codon usage varies among different members of the plant kingdom, indicating the necessity for species-specific study, this work has mostly been limited to model organisms. Recently, the development of deep sequencing, especial RNA-Seq, has made it possible to carry out studies in non-model species.Result: RNA-Seq data of Chinese bayberry was analyzed to investigate the bias of codon usage and codon pairs. High frequency codons (AGG, GCU, AAG and GAU), as well as low frequency ones (NCG and NUA codons) were identified, and 397 high frequency codon pairs were observed. Meanwhile, 26 preferred and 141 avoided neighboring codon pairs were also identified, which showed more significant bias than the same pairs with one or more intervening codons. Codon patterns were also analyzed at the plant kingdom, organism and gene levels. Changes during plant evolution were evident using RSCU (relative synonymous codon usage), which was even more significant than GC3s (GC content of 3rd synonymous codons). Nine GO categories were differentially and independently influenced by CAI (codon adaptation index) or GC3s, especially in 'Molecular function' category. Within a gene, the average CAI increased from 0.720 to 0.785 in the first 50 codons, and then more slowly thereafter. Furthermore, the preferred as well as avoided codons at the position just following the start codon AUG were identified and discussed in relation to the key positions in Kozak sequences. A comprehensive codon usage Table and number of high-frequency codon pairs were established. Bias in codon usage as well as in neighboring codon pairs was observed, and the significance of this in avoiding DNA mutation, increasing protein production and regulating protein synthesis rate was proposed. Codon usage patterns at three levels were revealed and the significance in plant evolution analysis, gene function classification, and protein translation start site predication were discussed. This work promotes the study of codon biology, and provides some reference for analysis and comprehensive application of RNA-Seq data from other non-model species.
    Preview · Article · Oct 2013 · BMC Genomics
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    ABSTRACT: The effects of acetylsalicylic acid (ASA) on kiwifruit (Actinidia deliciosa cvs Bruno and Hayward) ethylene biosynthesis and signaling were investigated. Exogenous application of ASA inhibited ethylene production in both whole fruit, and in vitro with flesh discs, and enzymes associated with ethylene biosynthesis (ACS and ACO). The effect of ASA treatment on kiwifruit softening was relatively weak. Combination treatments also had inhibitory effects on fruit ripening, with ASA + C2H4 more effective than C2H4 + ASA. In order to evaluate the effects of ASA on ethylene signaling, twenty-four ethylene signaling components (five ethylene receptors, two CTR1 like genes, four EIN3-like genes and thirteen ERF genes) were analyzed at the transcriptional level. The results indicated that ASA treatment generally inhibited ethylene-induced modulation of ethylene receptor genes, and had little effect on softening-related ethylene signaling components, which suggested that ASA inhibits fruit ripening mainly by interfering directly with ethylene biosynthesis and perception. In addition, the ethylene response factors AdERF1, AdERF3 and AdERF12 were characterized as ASA-responsive genes, and their roles in fruit stress response are also discussed.
    No preview · Article · Sep 2013 · Postharvest Biology and Technology
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    ABSTRACT: MrMYB1, an R2R3 MYB transcription factor (TF) gene associated with anthocyanin biosynthesis in Chinese bayberry (Myrica rubra Sieb. and Zucc.), was introduced into Arabidopsis and tobacco (Nicotiana tabacum) under the control of the CaMV 35S promoter. Overexpression of MrMYB1 induced anthocyanin accumulation in all tissues of Arabidopsis as well as in petals, ovaries and young seeds of tobacco, but not in tobacco leaves. The anthocyanin biosynthetic pathway, including chalcone synthase (CHS), dihydroflavonol 4-reductase (DFR) and anthocyanidin synthase (ANS), and the basic helix-loop-helix (bHLH) transcriptional partner TRANSPARENT TESTA8 (TT8), were up-regulated significantly in MrMYB1-overexpressing Arabidopsis. In MrMYB1-overexpressing tobacco petals, ovaries and young seeds, anthocyanin biosynthetic genes and bHLH partners NtAn1a and NtAn1b, were up-regulated. In contrast, high expression of MrMYB1 in transgenic tobacco leaves did not induce the expression of anthocyanin biosynthesis. Unlike in petals and ovaries, the foliar transcript level of NtAn1a and NtAn1b was extremely low and not stimulated by MrMYB1 transformation. These results show that higher expression of an endogenous bHLH partner, either intrinsically or stimulated by exogenous gene transformation, is required for anthocyanin production in plant tissues, and the different abundance in endogenous bHLH transcript accounts for differential accumulation of anthocyanin in Arabidopsis and tobacco leaves. These findings demonstrate that higher levels of expression of an endogenous bHLH partner, either intrinsically or following genetic transformation, are required for anthocyanin production in plant tissues. Moreover, differences in levels of endogenous bHLH transcripts account for observed differential accumulation of anthocyanin in leaves of Arabidopsis and tobacco.
    No preview · Article · Jun 2013 · Plant Cell Tissue and Organ Culture
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    ABSTRACT: Organic acid and sugar balance is an important trait for fruit quality. The mandarin, Ponkan (Citrus reticulata Blanco cv. Ponkan) is rich in organic acids even at maturity, thus the fruit provide good material for the study of organic acid degradation. In the present research, hot air (40 °C, 2 d) treatment (HAT) was found to have significant effects on both degradation of the organic acids, especially on citric acid, and accumulation of soluble sugars, especially on fructose and glucose. Genes related to citric acid degradation related (CitAco1, CitAco2, CitAco3, CitIDH1, CitIDH2, CitIDH3, CitGAD4, CitGAD5 and CitGS2) and sucrose metabolism (CitAI1, CitAI3, CitNI1 and CitNI3) were isolated and transcription analyzed. HAT significantly up-regulated CitAco3, CitIDH2/3 and CitGAD4 expression, while having little effect on CitGS2. Sucrose metabolism related genes also differentially responded to HAT, with CitAI genes were induced and CitNI genes were relatively unchanged. It is proposed that HAT drove citric acid degradation via the GABA shunt pathway (especially by modulating CitAco3–CitIDH2/3–CitGAD4 cascade), but not the glycolysis pathway.
    Full-text · Article · Nov 2012 · Scientia Horticulturae
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    ABSTRACT: The persimmon fruit is a particularly good model for studying fruit response to hypoxia, in particular, the hypoxia-response ERF (HRE) genes. An anaerobic environment reduces fruit astringency by converting soluble condensed tannins (SCTs) into an insoluble form. Although the physiology of de-astringency has been widely studied, its molecular control is poorly understood. Both CO2 and ethylene treatments efficiently removed the astringency from ‘Mopan’ persimmon fruit, as indicated by a decrease in SCTs. Acetaldehyde, the putative agent for causing de-astringency, accumulated during these treatments, as did activities of the key enzymes of acetaldehyde synthesis, alcohol dehydrogenase (ADH), and pyruvate decarboxylase (PDC). Eight DkADH and DkPDC genes were isolated, and three candidates for a role in de-astringency, DkADH1, DkPDC1, and DkPDC2, were characterized by transcriptional analysis in different tissues. The significance of these specific isoforms was confirmed by principal component analysis. Transient expression in leaf tissue showed that DkPDC2 decreased SCTs. Interactions of six hypoxia-responsive ERF genes and target promoters were tested in transient assays. The results indicated that two hypoxia-responsive ERF genes, DkERF9 and DkERF10, were involved in separately regulating the DkPDC2 and DkADH1 promoters. It is proposed that a DkERF–DkADH/DkPDC cascade is involved in regulating persimmon de-astringency.
    Full-text · Article · Oct 2012 · Journal of Experimental Botany
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    ABSTRACT: Ethylene response factors (ERFs) play important roles in fruit ripening and abiotic stress response. After harvest, fruit such as kiwifruit are subject to a range of stresses associated with postharvest handling and storage treatments. There have been few attempts to evaluate fruit ERF responses in relation to such abiotic stress. Stress treatments including low temperature (0 °C), high temperature (35 °C), high CO2 (5%) and high water loss (∼10% RH air) were applied to freshly harvested mature kiwifruit. Expression patterns of 13 AdERF genes were followed. In response to the abiotic stresses, AdERF3, AdERF4, AdERF11, AdERF12 and AdERF14 were constitutively up-regulated, and AdERF1 was generally down-regulated, while the other AdERF genes showed no regular expression patterns. These data showed that AdERF genes differentially respond to abiotic stresses experienced by fruit during postharvest storage.
    No preview · Article · Apr 2012 · Postharvest Biology and Technology