Synergistic Effects of the Combined Application of MCP and Low O2 on Apple Fruit Ripening

We have studied the effects of MCP and low O2, applied singly and in combination, on apple fruit ripening at 1, 7, and 18 °C. The single application of 2 ppm MCP is more effective in delaying the onset of the C2H4 climacteric than is 1% O2. However, the combined application has a much larger effect than the single applications of either MCP or 1% O2. For instance, at 7 °C, the onset of the C2H4 climacteric occurs at 15, 50, and 90–95 days for the controls, 1% O2 and 2 ppm MCP, respectively, whereas the combined application of 2 ppm MCP and 1% O2 suppressed the initiation of the C2H4 climacteric for 200 days, the duration of the experiment. The retardation of the climacteric onset by the treatments is associated with the suppression of ACC-synthase (ACS1) and the putative receptor ERS1. The accumulation of their transcripts is critically dependent on the rate of C2H4 evolution. As expected, the combined application of MCP and 1% O2 completely suppressed the expression of both genes. Yet when the fruits were transferred to 18 °C in air, they ripened normally. A similar pattern of inhibition in response to the above treatments was also observed with a C2H4-dependent MAPK. The expression of ETR1, ETR2 and ACC-oxidase was not affected by the treatments. The nature of this strong effect of the combined application of MCP and low O2 is not clear. It should be pointed out that MCP does not inhibit the induction of hypoxic proteins such as ADH.

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MOLECULAR BIOLOGICAL INVESTIGATIONS OF ACC OXIDASE AND ITS EXPRESSION ATTENDING APPLE FRUIT RIPENING

Acta Horticulturae ◽

10.17660/actahortic.1995.379.1 ◽

1995 ◽

pp. 25-40 ◽

Cited By ~ 5

Author(s):

D.R. Dilley ◽

J. Kuai ◽

I.D. Wilson ◽

Y. Pekker ◽

Y. Zhu ◽

...

Keyword(s):

Fruit Ripening ◽

Acc Oxidase ◽

Apple Fruit

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Brassinosteroids Suppress Ethylene Biosynthesis via Transcription Factor BZR1 in Pear and Apple Fruit

10.1101/2020.02.27.968800 ◽

2020 ◽

Author(s):

Yinglin Ji ◽

Yi Qu ◽

Zhongyu Jiang ◽

Xin Su ◽

Pengtao Yue ◽

...

Keyword(s):

Transcription Factor ◽

Fruit Ripening ◽

Ethylene Production ◽

Plant Hormone ◽

Expression Profiles ◽

Acc Synthase ◽

Ethylene Biosynthesis ◽

Apple Fruit ◽

Pear Fruit ◽

Climacteric Fruit

ABSTRACTThe plant hormone ethylene is important for the ripening of climacteric fruit, such as pear (Pyrus ussuriensis), and the brassinosteroid (BR) class of phytohormones affects ethylene biosynthesis during ripening, although via an unknown molecular mechanism. Here, we observed that exogenous BR treatment suppressed ethylene production during pear fruit ripening, and that the expression of the transcription factor PuBZR1 was enhanced by epibrassinolide (EBR) treatment during pear fruit ripening. PuBZR1 was shown to interact with PuACO1, which converts 1-aminocyclopropane-1-carboxylic acid (ACC) to ethylene, and suppress its activity. We also observed that BR-activated PuBZR1 bound to the promoters of PuACO1 and of PuACS1a, which encodes ACC synthase, and directly suppressed their transcription. Moreover, PuBZR1 suppressed the expression of transcription factor PuERF2 by binding its promoter, and PuERF2 bound to the promoters of PuACO1 and PuACS1a. We concluded that PuBZR1 indirectly suppresses the transcription of PuACO1 and PuACS1a through its regulation of PuERF2. Ethylene production and the expression profiles of the corresponding apple (Malus domestica) homologs showed similar changes following EBR treatment. Together, these results suggest that BR-activated BZR1 suppresses ACO1 activity and the expression of ACO1 and ACS1a, thereby reducing ethylene production during pear and apple fruit ripening. This likely represents a conserved mechanism by which exogenous BR suppresses ethylene biosynthesis during climacteric fruit ripening.One-sentence summaryBR-activated BZR1 suppresses ACO1 activity and expression of ACO1 and ACS1a, which encode two ethylene biosynthesis enzymes, thereby reducing ethylene production during pear and apple fruit ripening.

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Expression of ACC synthase is enhanced earlier than that of ACC oxidase during fruit ripening of mume (Prunus mume )

Physiologia Plantarum ◽

10.1034/j.1399-3054.1999.100309.x ◽

1999 ◽

Vol 107 (3) ◽

pp. 319-328 ◽

Cited By ~ 13

Author(s):

Satoru Mita ◽

Chikako Kirita ◽

Masaya Kato ◽

Hiroshi Hyodo

Keyword(s):

Fruit Ripening ◽

Acc Oxidase ◽

Acc Synthase ◽

Prunus Mume

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Low Oxygen and Elevated Carbon Dioxide Atmospheres Inhibit Ethylene Biosynthesis in Preclimacteric and Climacteric Apple Fruit

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.122.4.542 ◽

1997 ◽

Vol 122 (4) ◽

pp. 542-546 ◽

Cited By ~ 23

Author(s):

James R. Gorny ◽

Adel A. Kader

Keyword(s):

Enzyme Activity ◽

Mrna Level ◽

Acc Oxidase ◽

Acc Synthase ◽

Transcript Abundance ◽

Ethylene Biosynthesis ◽

Apple Fruit ◽

Low Oxygen ◽

Rate Limiting Step

Autocatalytic C2H4 biosynthesis in preclimacteric apple fruit (Malus domestica Borkh. `Golden Delicious') was prevented by storage in atmospheres of 20% CO2-enriched air (17% O2 + 63% N2) or 0.25% O2 (balance N2). In preclimacteric fruit, both treatments inhibited C2H2 biosynthesis by suppressing expression of ACC synthase (ACC-S) at the mRNA level. ACC oxidase (ACC-O) mRNA abundance and in vitro enzyme activity also were impaired by these treatments. However, the conversion of ACC to C2H4 never became the rate limiting step in C2H4 biosynthesis. C2H4 biosynthesis also was effectively inhibited in climacteric apple fruit kept in air + 20% CO2 or 0.25% O2. Climacteric apples also exhibited suppressed expression of ACC-S at the mRNA level, while ACC-O transcript abundance, enzyme activity, and protein abundance were reduced only slightly. ACC-S is the key regulatory enzyme of C2H4 biosynthesis and is the major site at which elevated CO2 and reduced O2 atmospheres inhibit C2H4 biosynthesis, irrespective of fruit physiological maturity. Chemical names used: 1-aminocyclopropane-1-carboxcylic acid (ACC).

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Elevated CO2 and/or Low O2 Atmospheres Influence ACC Synthase and ACC Oxidase during Long-term Storage of `Golden Delicious' Apple Fruit

HortScience ◽

10.21273/hortsci.30.4.782c ◽

1995 ◽

Vol 30 (4) ◽

pp. 782C-782

Author(s):

James R. Gorny ◽

Adel A. Kader

Keyword(s):

Blot Analysis ◽

Acc Oxidase ◽

Acc Synthase ◽

Ethylene Biosynthesis ◽

Apple Fruit ◽

Long Term Storage ◽

Golden Delicious ◽

Compare And Contrast

The objective of this study was to compare and contrast the mode of action by which elevated carbon dioxide and/or reduced oxygen atmospheres inhibit ethylene biosynthesis. `Golden Delicious' apple fruit were placed at 0C in one of the following four atmospheres: 1) air; 2) air + 5% CO2; 3) 2% O2 + 98% N2; or 4) 2% O2 + 5% CO2 + 93% N2 and then sampled monthly for 4 months. Ethylene biosynthesis rates and in vitro ACC synthase activities were closely correlated in all treatments. In vitro ACC synthase activity and ethylene biosynthesis rates were lowest in fruit treated with 5% CO2 + 2% O2, while air-treated fruit had the highest ethylene biosynthesis rate and in vitro ACC synthase activity. Fruit treated with air + 5% CO2, or 2% O2 + 98% N2, had intermediate ethylene and in vitro ACC synthase activities. In vitro ACC oxidase was significantly different among treatments, but not as closely correlated with the ethylene biosynthesis rate as in vitro ACC synthase activity. Western blot analysis of the ACC oxidase protein was performed to determine if activity differences among treatments were correlated with the amount of enzyme present in vivo. ACC synthase and ACC oxidase mRNA transcript of abundance was determined via Northern blot analysis. Results will be discussed regarding how ethylene biosynthesis is inhibited at the molecular level by elevated CO2 and/or reduced O2.

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Cloning and characterisation of ripening-induced ethylene biosynthetic genes from non-climacteric pineapple (Ananas comosus) fruits

Functional Plant Biology ◽

10.1071/pp98013 ◽

1998 ◽

Vol 25 (5) ◽

pp. 513 ◽

Cited By ~ 35

Author(s):

Christopher Ian Cazzonelli ◽

Antonino Salvatore Cavallaro ◽

José Ramón Botella

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Fruit Ripening ◽

Acc Oxidase ◽

Acc Synthase ◽

Southern Analysis ◽

Ananas Comosus ◽

Northern Analysis ◽

Fruit Tissue ◽

Climacteric Fruit

To gain a better understanding of non-climacteric fruit ripening, pineapple was used as a model system to clone and characterise two ripening-inducible cDNAs coding for two enzymes of the ethylene biosynthetic pathway, 1-aminocyclopropane-1-carboxylate (ACC) synthase (acacc-1) and 1-aminocyclo-propane- 1-carboxylate oxidase (acaco-1) respectively. Due to the extreme acidity and high polyphenolic content of pineapple fruits, a method was optimised for the extraction of high quality RNA from fruit tissue. acacc-1 is a 1080 bp ACC synthase cDNA fragment encoding 360 amino acids including 10 of the 12 amino acid residues conserved in all aminotransferases. Comparison of the deduced amino acid sequence with previously reported ACC synthases shows between 52 and 67% similarity at the protein level. Southern analysis suggests the presence of only one copy of acacc-1 in the pineapple genome. Although some acacc-1 expression is detected in green fruits, there is a 16-fold increase in the level of acacc-1 in ripe fruit tissue. acaco-1 is a partial length cDNA clone of 611 bp which codes for 203 amino acids representing approximately 66% of the ACC oxidase open reading frame. Southern analysis suggests the presence of one or two copies of the gene in the pineapple genome. Northern analysis shows the expression of acaco-1 to be highly induced in wounded leaf tissue and to a lesser extent in ripening fruit tissue. The accumulation of ACC-synthase and ACC oxidase mRNAs during pineapple fruit ripening raises new questions about the putative role of ethylene during non-climacteric fruit ripening.

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Characterisation of indigenous apple accessions with respect to polymorphism of ACS1 and ACO1 genes

Acta agriculturae Serbica ◽

10.5937/aaser2152151m ◽

2021 ◽

Vol 26 (52) ◽

pp. 151-157

Author(s):

Slađana Marić ◽

Ivana Glišić ◽

Nebojša Milošević ◽

Sanja Radičević ◽

Milena Đorđević ◽

...

Keyword(s):

Acc Oxidase ◽

Acc Synthase ◽

Restriction Enzymes ◽

Enzymatic Digestion ◽

Apple Fruit ◽

Pcr Product ◽

Signalling Molecule ◽

Genes Encoding ◽

Breeding Programmes ◽

Important Position

Ethylene is the simplest signalling molecule with a hormone-like function that plays a major role in many developmental processes, including ripening of climacteric apple fruit. The allelic polymorphisms of ACS1 and ACO1 genes, encoding for ACC synthase and ACC oxidase, which catalyse the last two steps in the ethylene biochemical pathway, were analysed in nineteen indigenous apple accessions grown in individual growers' orchards in the regions of central and southwestern Serbia. A polymorphism was detected using the polymerase chain reaction (PCR) for the ACS1 gene and the additional enzymatic digestion of the PCR product with BamH1 and RsaI for the ACO1 gene. The ACS1-1 and ACS1-2 alleles of the ACS1 gene, as well as the a and c alleles of the ACO1 gene were identified. The polymorphisms observed upon PCRs and digestion with restriction enzymes were generated in two genotypes for both genes, i.e. the ACS1 gene - ACS1-1/1 and ACS1-1/2, and the ACO1 gene - aa and ac. Out of nineteen apple accessions, sixteen were homozygous for the allele ACS1-1 and three were heterozygous (ACS1-1/2); regarding the ACO1 genotype, fourteen were homozygous for the allele a and five were heterozygous (ac allelic constitution). The molecular survey in the current study provides an increase in the number of apple accessions with potential to be used as parents in breeding programmes, aiming to obtain high quality cultivars that retain fruit texture during long storage. Therefore, the heterozygous accessions for the ACS1 gene - 'J-LuN/1', 'Kraljica' and 'Šumatovka', may have an important position in future breeding programmes.

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