Effects of Ethylene Biosynthesis in Tomato Fruit as a Function of Maturity

Abstract The tomato non-ripening (nor) mutant generates a truncated 186-amino-acid protein (NOR186) and has been demonstrated previously to be a gain-of-function mutant. Here, we provide more evidence to support this view and answer the open question of whether the NAC-NOR gene is important in fruit ripening. Overexpression of NAC-NOR in the nor mutant did not restore the full ripening phenotype. Further analysis showed that the truncated NOR186 protein is located in the nucleus and binds to but does not activate the promoters of 1-aminocyclopropane-1-carboxylic acid synthase2 (SlACS2), geranylgeranyl diphosphate synthase2 (SlGgpps2), and pectate lyase (SlPL), which are involved in ethylene biosynthesis, carotenoid accumulation, and fruit softening, respectively. The activation of the promoters by the wild-type NOR protein can be inhibited by the mutant NOR186 protein. On the other hand, ethylene synthesis, carotenoid accumulation, and fruit softening were significantly inhibited in CR-NOR (CRISPR/Cas9-edited NAC-NOR) fruit compared with the wild-type, but much less severely affected than in the nor mutant, while they were accelerated in OE-NOR (overexpressed NAC-NOR) fruit. These data further indicated that nor is a gain-of-function mutation and NAC-NOR plays a significant role in ripening of wild-type fruit.

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A UV-light activated cinnamic acid isomer regulates plant growth and gravitropism via an ethylene receptor-independent pathway

Functional Plant Biology ◽

10.1071/pp99007 ◽

1999 ◽

Vol 26 (4) ◽

pp. 325 ◽

Cited By ~ 12

Author(s):

Xiao Xian Yang ◽

Hiu Wan Choi ◽

Shang Fa Yang ◽

Ning Li

Keyword(s):

Tomato Plant ◽

Uv Light ◽

Tomato Fruit ◽

Ethylene Biosynthesis ◽

Banana Fruit ◽

Ethylene Receptor ◽

Cinnamic Acids ◽

Tomato Plants ◽

Tomato Fruit Ripening ◽

Negative Gravitropism

Naturally occurring cinnamic acids (CA) exist in both trans- and cis-isoforms. UV-light irradiation of trans-CA is able to produce cis-CA. cis-CA was found to possess auxin-like activity before. In contrast, the vapor of cis-CA induced an epinastic response in tomato plants just as ethylene does. Given the existence of a double bond in and the gaseous nature of cis-CA, we suspected that cis-CA might also function as an ethylene-like compound. To distinguish between these possibilities, we selected an ethylene perception-deficient tomato plant, Never-ripe (Nr), and an ethylene biosynthesis-deficient tomato plant, A11. Not only did the vapor of cis-CA fail to trigger A11 tomato fruit ripening but it also delayed the ripening of banana fruit. Moreover, the vapor of cis-CA induced epinasty and the ‘triple response’ in both the wild type and Nr tomato plants, indicating that the vapor of cis-CA does not act via an ethylene receptor-dependent pathway. Furthermore, the vapor of cis-CA inhibited the negative gravitropic response of stems of both etiolated Nr seedlings and young plants, whereas ethylene had little effect on the negative gravitropism of the Nr plants. These results support the conclusion that the action sites of the vapor of cis-CA and ethylene are fundamentally different.

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Glucose Inhibits ACC Oxidase Activity and Ethylene Biosynthesis in Ripening Tomato Fruit

Plant Growth Regulation ◽

10.1023/b:grow.0000038248.54232.6a ◽

2004 ◽

Vol 43 (1) ◽

pp. 81-87 ◽

Cited By ~ 9

Author(s):

Ji Heun Hong ◽

A. Keith Cowan ◽

Seung Koo Lee

Keyword(s):

Oxidase Activity ◽

Tomato Fruit ◽

Acc Oxidase ◽

Ethylene Biosynthesis

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Comprehensive Analysis of ABA Effects on Ethylene Biosynthesis and Signaling during Tomato Fruit Ripening

PLoS ONE ◽

10.1371/journal.pone.0154072 ◽

2016 ◽

Vol 11 (4) ◽

pp. e0154072 ◽

Cited By ~ 41

Author(s):

Wangshu Mou ◽

Dongdong Li ◽

Jianwen Bu ◽

Yuanyuan Jiang ◽

Zia Ullah Khan ◽

...

Keyword(s):

Fruit Ripening ◽

Tomato Fruit ◽

Ethylene Biosynthesis ◽

Comprehensive Analysis ◽

Tomato Fruit Ripening ◽

Ethylene Biosynthesis And Signaling

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PECTIN OLIGOMERS - POTENTIAL ENDOGENOUS REGULATORS OF RIPENING?

HortScience ◽

10.21273/hortsci.27.6.653g ◽

1992 ◽

Vol 27 (6) ◽

pp. 653g-653

Author(s):

Eunice Melotto ◽

L. Carl Greve ◽

John M. Labavitch

Keyword(s):

Biological Activity ◽

Acid Hydrolysis ◽

Ethylene Production ◽

Tomato Fruit ◽

Ethylene Biosynthesis ◽

Polygalacturonic Acid ◽

Ripening Process ◽

Size Classes ◽

Endogenous Regulators ◽

Fruit Pericarp

Acid hydrolysis-generated pectic oligomers have been shown to affect ripening of tomato fruit by inducing both acceleration of reddening and increased ethylene biosynthesis (Campbell & Labavitch, 1991 Plant Physiol 97:706-713). In the present work, homogeneous size classes of these oligomers were demonstrated to have different impacts on ethylene production of tomato fruit pericarp discs. Endogenous oligomeric material of the same size classes was isolated from ripening tomato tissues and also tested for biological activity. They promoted some aspects of ripening as shown by increased ACC and ethylene production, which suggests that pectic oligomers are potential regulators of the ripening process in tomatoes. A metabolic origin for these oligomers is suggested by the fact that they are produced by in vitro polygalacturonase I treatment of polygalacturonic acid or tomato pectin.

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Reduced 5'-Methylthioadenosine Nucleosidase and 5-Methylthioribose Activities and Ethylene Biosynthesis in Nonripening Tomato Mutants `Rin' and `Nor' Relative to Ripening Tomato `Rutgers'

HortScience ◽

10.21273/hortsci.31.4.687f ◽

1996 ◽

Vol 31 (4) ◽

pp. 687f-688

Author(s):

Chunlin Xiao ◽

Mosbah M. Kushad

Keyword(s):

Fruit Development ◽

Tomato Fruit ◽

Maximum Level ◽

Ethylene Biosynthesis ◽

Fruit Growth ◽

Ethylene Synthesis ◽

Fruit Maturity ◽

Growth Development ◽

Relationship Of

5'-methylthioadenosine (MTA) nucleosidase (EC.2.2.2.28) and 5-methylthioribose (MTR) kinase (EC.2.7.1.100) activities were evaluated in `rin', `nor', and `Rutgers' tomato fruit during development and ripening. Changes in the activities of these enzymes were compared to ethylene biosynthesis. MTA nucleosidase and MTR kinase activities in `rin' and `nor' were ≈30% and 22%, respectively, lower than `Rutgers' during the first 2 weeks of fruit development. In `Rutgers', activities of these enzymes declined sharply until fruit maturity. Shortly before climacteric rise in ethylene synthesis, MTA nucleosidase, and MTR kinase activities increased, reaching a maximum level before peak ethylene synthesis then declined when fruit started to approach senescence. Whereas, `rin' and `nor' mutants exhibited no climacteric rise in ethylene synthesis and no change in MTA nucleosidase or MTR kinase activities, following their decline after 2 weeks of growth. A rapid increase in ethylene synthesis was observed when mature green `rin' and `nor' fruit were wounded. This increase in ethylene was paralleled by an increase in MTA nucleosidase and MTR kinase activities. However, increase in wound ethylene, MTA nucleosidase, and MTR kinase activities in `rin' and `nor' was ≈40% less than what we had previously reported in `Rutgers'. Relationship of MTA and MTR kinase activities to fruit growth, development, ripening, and natural and wound ethylene biosynthesis will be described.

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