Transcriptome analysis around the onset of strawberry fruit ripening uncovers an important role of oxidative phosphorylation in ripening

Abstract

Although much progress has been made towards understanding the ripening of non-climacteric fruit using the strawberry as a model plant, the defined molecular mechanisms remain unclear. Here, RNA-sequencing was performed using four cDNA libraries around the onset of ripening, and a total of 31,793 unigenes and 335 pathways were annotated including the top five pathways, which were involved in ribosome, spliceosome, protein processing, plant-pathogen interaction and plant hormone signaling, and the important DEGs related to ripening were annotated to be mainly involved in protein translation and processing, sugar metabolism, energy metabolism, phytohormones, antioxidation, pigment and softening, especially finding a decreased trend of oxidative phosphorylation during red-coloring. VIGS-mediated downregulation of the pyruvate dehydrogenase gene PDHE1α, a key gene for glycolysis-derived oxidative phosphorylation, could inhibit respiration and ATP biosynthesis, whilst promote the accumulation of sugar, ABA, ETH, and PA, ultimately accelerating the ripening. In conclusion, our results demonstrate that a set of metabolism transition occurred during green-to-white-to-red stages that are coupled with more-to-less DEGs, and the oxidative phosphorylation plays an important role in the regulation of ripening. On the basis of our results, we discuss an oxidative phosphorylation-based model underlying strawberry fruit ripening.

Grey mould of strawberry, a devastating disease caused by the ubiquitous necrotrophic fungal pathogen Botrytis cinerea

“…Recent transcriptomic studies of developing strawberries point out that ripening events start between the ‘large green’ and ‘white’ stages, and involve changes in cell wall composition, sugar metabolism, hormone biosynthesis and responses, pigmentation and antioxidant levels (Guo et al , ; Sanchez‐Sevilla et al , ; Wang et al , ). Moreover, a general decrease of oxidative phosphorylation processes has been observed during strawberry ripening (Sanchez‐Sevilla et al , 2017; Wang et al , ). Normal strawberry ripening involves a variety of biochemical and physiological processes, some of which are discussed below in the context of B. cinerea interactions.…”

“…Moreover, B. cinerea can synthesize and secrete ABA that functions as a virulence factor (Siewers et al , 2006). Besides hormones, increased oxidative reactions caused by the pathogen may influence ripening progression (Bianco et al , ; Wang et al , ).…”

Genome-wide interologous interactome map (TeaGPIN) ofCamellia sinensis

“…Also, in metabolism, oxidative phosphorylation category under energy metabolism is enriched with 44 proteins (17 proteins from Module_9, 10 proteins from Module_5, 5 proteins from Module_7, 4 proteins each from Module_2 and Module_6, 1 protein from Module_3 and Module_1 and 2 proteins from Module_10). Oxidative phosphorylation has important role in regulating cellular processes like respiration and ATP biosynthesis for plant metabolic activities [69].…”

Sigma factor FaSigE positively regulates strawberry fruit ripening by ABA

“…The prepared libraries were sequenced using the Illumina HiSeq 2000 platform (Illumina, USA). The data analysis was done according to the description (Benjamini and Yekutieli 2001;Mortazavi et al 2008;Wang et al 2010Wang et al , 2017Langmead and Salzberg 2012;Ming et al 2012).…”