Dataset Information

PpARF6 acts as an integrator of auxin and ethylene signaling to promote fruit ripening in peach.

ABSTRACT: Although auxin is known to induce ethylene biosynthesis in some Rosaceae fruit crops, the mechanisms underlying the auxin-ethylene interaction during fruit ripening remain largely unknown. Here, the regulatory role of an auxin response factor, PpARF6, in fruit ripening was investigated in peach. Peach fruits showed accelerated ripening after treatment with auxin and PpARF6 was found to be significantly induced. PpARF6 not only could induce ethylene synthesis by directly activating the transcription of ethylene biosynthetic genes, but also competed with EIN3-binding F-box proteins PpEBF1/2 for binding to ethylene-insensitive3-like proteins PpEIL2/3, thereby keeping PpEIL2/3 active. Moreover, PpARF6 showed an interaction with PpEIL2/3 to enhance the PpEIL2/3-activated transcription of ethylene biosynthetic genes. Additionally, ectopic overexpression of PpARF6 in tomato accelerated fruit ripening by promoting the expression of genes involved in ethylene synthesis and fruit texture. In summary, our results revealed a positive regulatory role of PpARF6 in peach fruit ripening via integrating auxin and ethylene signaling.

SUBMITTER: Chen X

PROVIDER: S-EPMC10500152 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

PpARF6 acts as an integrator of auxin and ethylene signaling to promote fruit ripening in peach.

Chen Xiaomei X Liu Yudi Y Zhang Xian X Zheng Beibei B Han Yuepeng Y Zhang Ruo-Xi RX

Horticulture research 20230731 9

Although auxin is known to induce ethylene biosynthesis in some Rosaceae fruit crops, the mechanisms underlying the auxin-ethylene interaction during fruit ripening remain largely unknown. Here, the regulatory role of an auxin response factor, PpARF6, in fruit ripening was investigated in peach. Peach fruits showed accelerated ripening after treatment with auxin and PpARF6 was found to be significantly induced. PpARF6 not only could induce ethylene synthesis by directly activating the transcript ...[more]

PMID: 37719277

Similar Datasets

Project description:Light signaling and plant hormones, particularly ethylene and auxins, have been identified as important regulators of carotenoid biosynthesis during tomato fruit ripening. However, whether and how the light and hormonal signaling cascades crosstalk to control this metabolic route remain poorly elucidated. Here, the potential involvement of ethylene and auxins in the light-mediated regulation of tomato fruit carotenogenesis was investigated by comparing the impacts of light treatments and the light-hyperresponsive high pigment-2 (hp2) mutation on both carotenoid synthesis and hormonal signaling. Under either light or dark conditions, the overaccumulation of carotenoids in hp2 ripening fruits was associated with disturbed ethylene production, increased expression of genes encoding master regulators of ripening and higher ethylene sensitivity and signaling output. The increased ethylene sensitivity observed in hp2 fruits was associated with the differential expression of genes encoding ethylene receptors and downstream signaling transduction elements, including the downregulation of the transcription factor ETHYLENE RESPONSE FACTOR.E4, a repressor of carotenoid synthesis. Accordingly, treatments with exogenous ethylene promoted carotenoid biosynthetic genes more intensively in hp2 than in wild-type fruits. Moreover, the loss of HP2 function drastically altered auxin signaling in tomato fruits, resulting in higher activation of the auxin-responsive promoter DR5, severe down-regulation of AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) genes and altered accumulation of AUXIN RESPONSE FACTOR (ARF) transcripts. Both tomato ARF2 paralogues (Sl-ARF2a and SlARF2b) were up-regulated in hp2 fruits, which agrees with the promotive roles played by these ARFs in tomato fruit ripening and carotenoid biosynthesis. Among the genes differentially expressed in hp2 fruits, the additive effect of light treatment and loss of HP2 function was particularly evident for those encoding carotenoid biosynthetic enzymes, ethylene-related transcription factors, Aux/IAAs and ARFs. Altogether, the data uncover the involvement of ethylene and auxin as part of the light signaling cascades controlling tomato fruit metabolism and provide a new link between light signaling, plant hormone sensitivity and carotenoid metabolism in ripening fruits.

Project description:Fruit ripening is a highly coordinated developmental process driven by a complex hormonal network. Ethylene is the main regulator of climacteric fruit ripening. However, a putative role of other key phytohormones in this process cannot be excluded. We previously observed an increasing level of auxin during the post-harvest ripening of the durian fruit, which occurred concomitantly with the rise in the climacteric ethylene biosynthesis. Herein, we connect the key auxin signaling component, auxin response factors (ARFs), with the regulatory network that controls fruit ripening in durian through the identification and functional characterization of a candidate ripening-associated ARF. Our transcriptome-wide analysis identified 15 ARF members in durian (DzARFs), out of which 12 were expressed in the fruit pulp. Most of these DzARFs showed a differential expression, but DzARF2A had a marked ripening-associated expression pattern during post-harvest ripening in Monthong, a commercial durian cultivar from Thailand. Phylogenetic analysis of DzARF2A based on its tomato orthologue predicted a role in ripening through the regulation of ethylene biosynthesis. Transient expression of DzARF2A in Nicotiana benthamiana leaves significantly upregulated the expression levels of ethylene biosynthetic genes, pointing to a ripening-associated role of DzARF2A through the transcriptional regulation of ethylene biosynthesis. Dual-luciferase reporter assay determined that DzARF2A trans-activates durian ethylene biosynthetic genes. We previously reported significantly higher auxin level during post-harvest ripening in a fast-ripening cultivar (Chanee) compared to a slow-ripening one (Monthong). DzARF2A expression was significantly higher during post-harvest ripening in the fast-ripening cultivars (Chanee and Phuangmanee) compared to that of the slow-ripening ones (Monthong and Kanyao). Thus, higher auxin level could upregulate the expression of DzARF2A during ripening of a fast-ripening cultivar. The auxin-induced expression of DzARF2A confirmed its responsiveness to exogenous auxin treatment in a dose-dependent manner, suggesting an auxin-mediated role of DzARF2A in fruit ripening. We suggest that high DzARF2A expression would activate ARF2A-mediated transcription of ethylene biosynthetic genes, leading to increased climacteric ethylene biosynthesis (auxin-ethylene crosstalk) and faster ripening. Hence, we demonstrated DzARF2A as a new component of the regulatory network possibly mediating durian fruit ripening through transcriptional regulation of ethylene biosynthetic genes.

Project description:BackgroundIn melting flesh peaches, auxin is necessary for system-2 ethylene synthesis and a cross-talk between ethylene and auxin occurs during the ripening process. To elucidate this interaction at the transition from maturation to ripening and the accompanying switch from system-1 to system-2 ethylene biosynthesis, fruits of melting flesh and stony hard genotypes, the latter unable to produce system-2 ethylene because of insufficient amount of auxin at ripening, were treated with auxin, ethylene and with 1-methylcyclopropene (1-MCP), known to block ethylene receptors. The effects of the treatments on the different genotypes were monitored by hormone quantifications and transcription profiling.ResultsIn melting flesh fruit, 1-MCP responses differed according to the ripening stage. Unexpectedly, 1-MCP induced genes also up-regulated by ripening, ethylene and auxin, as CTG134, similar to GOLVEN (GLV) peptides, and repressed genes also down-regulated by ripening, ethylene and auxin, as CTG85, a calcineurin B-like protein. The nature and transcriptional response of CTG134 led to discover a rise in free auxin in 1-MCP treated fruit. This increase was supported by the induced transcription of CTG475, an IAA-amino acid hydrolase. A melting flesh and a stony hard genotype, differing for their ability to synthetize auxin and ethylene amounts at ripening, were used to study the fine temporal regulation and auxin responsiveness of genes involved in the process. Transcriptional waves showed a tight interdependence between auxin and ethylene actions with the former possibly enhanced by the GLV CTG134. The expression of genes involved in the regulation of ripening, among which are several transcription factors, was similar in the two genotypes or could be rescued by auxin application in the stony hard. Only GLV CTG134 expression could not be rescued by exogenous auxin.Conclusions1-MCP treatment of peach fruit is ineffective in delaying ripening because it stimulates an increase in free auxin. As a consequence, a burst in ethylene production speeding up ripening occurs. Based on a network of gene transcriptional regulations, a model in which appropriate level of CTG134 peptide hormone might be necessary to allow the correct balance between auxin and ethylene for peach ripening to occur is proposed.

Dataset Information

PpARF6 acts as an integrator of auxin and ethylene signaling to promote fruit ripening in peach.

Publications

PpARF6 acts as an integrator of auxin and ethylene signaling to promote fruit ripening in peach.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets