Biology and genetic engineering of fruit maturation for enhanced quality and shelf-life

doi:10.1016/j.copbio.2009.02.015

Current Opinion in Biotechnology

Volume 20, Issue 2, April 2009, Pages 197-203

https://doi.org/10.1016/j.copbio.2009.02.015 Get rights and content

Commercial regulation of ripening is currently achieved through early harvest, by controlling the postharvest storage atmosphere and genetic selection for slow or late ripening varieties. Although these approaches are often effective, they are not universally applicable and often result in acceptable, but poor quality, products. With increased understanding of the molecular biology underlying ripening and the advent of genetic engineering technologies, researchers have pursued new strategies to address problems in fruit shelf-life and quality. These have been guided by recent insights into mechanisms by which ethylene and a complex network of transcription factors regulate ripening, and by an increased appreciation of factors that contribute to shelf-life, such as the fruit cuticle.

Section snippets

Ethylene and fruit ripening

Ripening is regulated by both internal and external stimuli, including temperature, light, plant nutrient status, water availability, and hormones. Many fruits, in particular the so-called climacteric fruits, require ethylene for ripening, resulting in the targeting of this hormone as a means of ripening control. Although nonclimacteric fruits typically produce little ethylene during ripening, many have still been shown to be affected by exogenous ethylene during ripening, making ethylene

Ethylene response genes: potential targets for ethylene response and ripening control

Ethylene signal transduction genes have been well characterized in Arabidopsis (for recent reviews see [4, 5, 6]). More recent efforts in understanding the ethylene response during fruit ripening have focused on the characterization of tomato homologs. All the components of the Arabidopsis ethylene signal transduction analyzed thus far are conserved in tomato (reviewed in [2]). However, the family size and expression profiles of some of these genes differ between Arabidopsis and tomato. For

Transcriptional control of fruit ripening and conserved ripening regulators

Although considerable effort has focused on ethylene synthesis and response, only recently have inroads been made into understanding ripening control before ethylene: a regulatory system that is possibly conserved between climacteric and nonclimacteric species. Recently, the mutated genes underlying the ripening mutants RIPENING INHIBITOR (RIN) and COLOURLESS NON RIPENING (CNR) were cloned, providing key insights into the regulation of the ripening process upstream of ethylene. The rin and Cnr

Genetic manipulation of ripening regulatory genes

To date, attempts to manipulate the expression of target genes during fruit ripening have produced varying results. As mentioned, transcriptional control has been utilized with respect to breeding for heterozygosity at the rin mutation (Rin/rin) in commercial lines to delay ripening and extend shelf-life; however, this modification leads to the inhibition of flavor and nutritional compound accumulation along with undesirable textural traits in some backgrounds due to incomplete ripening. In

Cell walls and cuticles as key factors for fruit shelf-life

The cell wall has a profoundly important influence on fruit texture and cell wall components and the underlying genes have been frequent targets for genetic engineering, mostly in tomato, with the goal of extending shelf-life [19, 20]. Although knowledge of the mechanism of fruit softening has grown in recent years, it has proven especially difficult to establish the relationship between specific aspects of cell wall metabolism or architecture and their relationship to changes in tissue

When a fruit is more than a fruit?

Fresh fruits and their processed derivates represent important sources of carotenoids, flavonoids, and anthocyanins and the possibility of improving content using bioengineering represent an opportunity to improve access to healthy foods. The inherent resiliency of plant metabolism to maintain homeostasis has impaired efforts to facilitate changes in some of these pathways, as has been especially well documented for carotenoids [29]. An alternate approach is to focus on regulatory rather than

New tools, new strategies, and enhancement of traditional approaches

Prior efforts toward fruit quality improvement have focused on single steps in biochemical pathways, but complex feedback regulation networks have complicated such strategies, as noted above. Targeting regulatory genes may provide a route to avoid these regulatory impediments though the difficult work of assessing the impact of altering specific pathway steps is required to understand the underlying regulatory networks [32]. The use of a transcription factor that regulates a complete

Prospects for the future

It is important to note that recent studies have reported that genetically modified organisms are not inherently dangerous and can be considered safe to consumers when compared with conventional foods developed for target traits through naturally occurring genetic variation [49]. Of course, given that the safety of crops is a primary concern for both producers and consumers, it is necessary to define the risk and unintended effects in genetically modified plants [50], including the effects of a

References and recommended reading

Papers of particular interest, published within the period of review, have been highlighted as:

• of special interest
•• of outstanding interest

Acknowledgements

We acknowledge the support from USDA-NRI grants 2007-02773 and 2006-35304-17323, and the NSF Plant Genome grants 05-01778 and 06-06595. Support was also provided by a grant to JKCR from the US–Israel Binational Science Foundation, and to NEG from the New Zealand Foundation for Research, Science and Technology FRST-BTPR0701.

References (54)

J.J. Giovannoni
Fruit ripening mutants yield insights into ripening control
Curr Opin Plant Biol
(2007)
M.D. Kendrick et al.
Ethylene signaling: new levels of complexity and regulation
Curr Opin Plant Biol
(2008)
R. Hovav et al.
The identification of a gene (Cwp1), silenced during Solanum evolution, which causes cuticle microfissuring and dehydration when expressed in tomato fruit
Plant J
(2007)
J.J. Giovannoni
Genetic regulation of fruit development and ripening
Plant Cell
(2004)
S.A. Goff et al.
Plant volatile compounds: sensory cues for health and nutritional value?
Science
(2006)
L.M. Benavente et al.
Molecular mechanisms of ethylene signaling in Arabidopsis
Mol Biosys
(2006)
A. Hahn et al.
Mitogen-Activated Protein kinase cascades and ethylene — signaling, biosynthesis or both?
Plant Physiol
(2008)
S. Zhong et al.
Tomato ethylene receptor–CTR interactions: visualization of NEVER-RIPE interactions with multiple CTRs at the endoplasmic reticulum
J Exp Bot
(2008)
C.S. Barry et al.
Ripening in the tomato Green-ripe mutant is inhibited by ectopic expression of a protein that disrupts ethylene signaling
Proc Natl Acad Sci U S A
(2006)
J.S. Resnick et al.
REVERSION-TO-ETHYLENE SENSITIVITY1, a conserved gene that regulates ethylene receptor function in Arabidopsis
Proc Natl Acad Sci U S A
(2006)

J. Leide et al.

The developmental pattern of tomato fruit wax accumulation and its impact on cuticular transpiration barrier properties: effects of a deficiency in a beta-ketoacyl-coenzyme A synthase (LeCER6)

Plant Physiol

(2007)

T.R. Thomas et al.

Mesocarp cell turgor in Vitis vinifera L. berries throughout development and its relation to firmness, growth, and the onset of ripening

Planta

(2008)

Cited by (123)

Fruit transcriptional profiling of the contrasting genotypes for shelf life reveals the key candidate genes and molecular pathways regulating post-harvest biology in cucumber
2022, Genomics
Cucumber fruits are perishable in nature and become unfit for market within 2–3 days of harvesting. A natural variant, DC-48 with exceptionally high shelf life was developed and used to dissect the genetic architecture and molecular mechanism for extended shelf life through RNA-seq for first time. A total of 1364 DEGs were identified and cell wall degradation, chlorophyll and ethylene metabolism related genes played key role. Polygalacturunase (PG), Expansin (EXP) and xyloglucan were down regulated determining fruit firmness and retention of fresh green colour was mainly attributed to the low expression level of the chlorophyll catalytic enzymes (CCEs). Gene regulatory networks revealed the hub genes and cross-talk associated with wide variety of the biological processes. Large number of SSRs (21524), SNPs (545173) and InDels (126252) identified will be instrumental in cucumber improvement. A web genomic resource, CsExSLDb developed will provide a platform for future investigation on cucumber post-harvest biology.
The tomato long shelf-life fruit phenotype: Knowledge, uncertainties and prospects
2022, Scientia Horticulturae
The long shelf-life (LSL) phenotype is characteristic of diverse Mediterranean tomato landraces and is defined by the outstanding durability of the fruit, showing no symptoms of deterioration for up to ten months after harvest. The genetic basis behind this abnormal phenotype is yet to be fully characterized, though many ripening-related mutants have been identified and studied during the past decades. New technologies have allowed for a deeper understanding of the genetic background of this trait and have revealed that the LSL phenotype is dependent on more traits beyond the ethylene synthesis and response pathways. Nevertheless, full determination of ethylene synthesis levels in mutants of commercial interest, such as rin, nor and alc, warrants some further research as to describe to what extent these mutations affect ethylene response. Available data suggests that singular mutations are not enough to lead to the LSL phenotype. Particularly, the role of the alc allele is not entirely clear, as newer studies suggest this mutation alone is not responsible for this phenotype in landraces that naturally present it, summed to the fact that Italian LSL landraces do not harbor this particular allele. The molecular traits underlying the LSL phenotype have been increasingly studied for the past decades and it becomes clear that it is far more complex than originally believed, and that traits other than the alc mutation must be involved in this phenotype. This review aims to recapitulate the research performed in this area and highlight the questions that are still to be answered to fully explain the basis of this outstanding fruit phenotype.
Physiological mechanisms and adaptation strategies of plants under nutrient deficiency and toxicity conditions
2021, Plant Perspectives to Global Climate Changes: Developing Climate-Resilient Plants
Presently, the world is suffering from the declining trend of crop yields globally, making food security a major challenge. The limited availability of arable land and water resources has made this challenge even bigger. Recent research-based studies depict that, in many developing countries, poor soil fertility, lower availability of mineral nutrients in soil, improper nutrient management, along with the lack of plant genotypes having high tolerance to nutrient deficiencies or toxicities are major constraints leading to food insecurity, malnutrition (i.e., micronutrient deficiencies), and degradation of ecosystem. It has been stated that 60% of our cultivated soils have growth-limiting problems with deficiencies and toxicities of available mineral nutrients. About 50% of the world population suffers from micronutrient deficiencies that make mineral nutrition studies a major promising area in meeting the global demand for sufficient food production with enhanced nutritional value. Integration of plant adaptation strategies in such soils using genetics and plant breeding and molecular biology is indispensable in developing plant genotypes with high genetic potential to acclimatize such nutrient-deficient and toxic soil conditions to translocate more micronutrients into edible plant parts such as cereal grains. Thus, plant nutrition research provides invaluable information, which is highly useful in elimination of these constraints, and leads to sustain the food security and well-being of humans without harming the environment. Keeping all these points in mind this chapter helps in understanding the mechanisms and strategies of plant in nutrient-deficient and toxic soil conditions.
Vegetable seeds: Production and technology
2024, Vegetable Seeds: Production and Technology
Identification and evaluation of potential beef tomato elders for the crossing material of NIL-Sletr1-2
2023, Research on Crops
Designing of future ornamental crops: a biotechnological driven perspective
2023, Horticulture Research

View all citing articles on Scopus

^*: These authors contributed equally to this manuscript and should be considered co-first authors.

View full text

Biology and genetic engineering of fruit maturation for enhanced quality and shelf-life

Section snippets

Ethylene and fruit ripening

Ethylene response genes: potential targets for ethylene response and ripening control

Transcriptional control of fruit ripening and conserved ripening regulators

Genetic manipulation of ripening regulatory genes

Cell walls and cuticles as key factors for fruit shelf-life

When a fruit is more than a fruit?

New tools, new strategies, and enhancement of traditional approaches

Prospects for the future

References and recommended reading

Acknowledgements

Curr Opin Plant Biol

Curr Opin Plant Biol

Plant J

Genetic regulation of fruit development and ripening

Plant Cell

Plant volatile compounds: sensory cues for health and nutritional value?

Science

Molecular mechanisms of ethylene signaling in Arabidopsis

Mol Biosys

Mitogen-Activated Protein kinase cascades and ethylene — signaling, biosynthesis or both?

Plant Physiol

Tomato ethylene receptor–CTR interactions: visualization of NEVER-RIPE interactions with multiple CTRs at the endoplasmic reticulum

J Exp Bot

Ripening in the tomato Green-ripe mutant is inhibited by ectopic expression of a protein that disrupts ethylene signaling

Proc Natl Acad Sci U S A

REVERSION-TO-ETHYLENE SENSITIVITY1, a conserved gene that regulates ethylene receptor function in Arabidopsis

Proc Natl Acad Sci U S A

Ethylene insensitivity conferred by the Green-ripe and Never-ripe 2 ripening mutants of tomato

Plant Physiol

Ethylene receptor degradation controls the timing of ripening in tomato fruit

Plant J

SlTPR1, a tomato tetratricopeptide repeat protein, interacts with the ethylene receptors NR and LeETR1, modulating ethylene and auxin responses and development

J Exp Bot

A MADS-box gene necessary for fruit ripening at the tomato Ripening-inhibitor (Rin) locus

Science

A naturally occurring epigenetic mutation in a gene encoding an SBP-box transcription factor inhibits tomato fruit ripening

Nat Genet

Molecular and phylogenetic analyses of the MADS-Box gene family in tomato

Mol Biol Evol

A tomato HD-Zip homeobox protein, LeHB-1, plays an important role in floral organogenesis and ripening

Plant J

Fruit-specific RNAi-mediated suppression of DET1 enhances carotenoid and flavonoid content in tomatoes

Nat Biotechnol

Transcriptome and selected metabolite analyses reveal multiple points of ethylene control during tomato fruit development

Plant Cell

The linkage between cell wall metabolism and fruit softening: looking to the future

J Sci Food Agric

Cell wall modifications during fruit ripening: when a fruit is not the fruit

Trends Food Sci Technol

Down-regulation of an auxin response factor in the tomato induces modification of fine pectin structure and tissue architecture

J Exp Bot

Rin, norA, ogc and hp mutants in tomatoes with different genetic backgrounds

Pesquisa Agropecuaria Brasileira

Melon, an alternative model plant for elucidating fruit ripening

Plant Sci

A reevaluation of the key factors that influence tomato fruit softening and integrity

Plant Physiol

The developmental pattern of tomato fruit wax accumulation and its impact on cuticular transpiration barrier properties: effects of a deficiency in a beta-ketoacyl-coenzyme A synthase (LeCER6)

Plant Physiol

Mesocarp cell turgor in Vitis vinifera L. berries throughout development and its relation to firmness, growth, and the onset of ripening

Planta

Rin, nor^A, og^c and hp mutants in tomatoes with different genetic backgrounds