Genome-Wide Analysis of ATP Binding Cassette (ABC) Transporters in Peach () and Identification of a Gene Involved in Anthocyanin Accumulation.

The ATP-binding cassette (ABC) transporter family is a large and diverse protein superfamily that plays various roles in plant growth and development. Although the ABC transporters are known to aid in the transport of a wide range of substrates across biological membranes, their role in anthocyanin transport remains elusive. In this study, we identified a total of 132 putative genes in the peach genome, and they were phylogenetically classified into eight subfamilies.

Two vacuolar invertase inhibitors PpINHa and PpINH3 display opposite effects on fruit sugar accumulation in peach.

Soluble sugars are an important determinant of fruit taste, but their accumulation mechanisms remain elusive. In this study, we report two vacuolar invertase inhibitor genes involved in sugar accumulation in peach, and . Transient overexpression of in peach fruits resulted in an increase in sugar content, while the opposite trend was detected for .

Epigenetic reprogramming of H3K27me3 and DNA methylation during leaf-to-callus transition in peach.

Plant tissues are capable of developing unorganized cell masses termed calluses in response to the appropriate combination of auxin and cytokinin. Revealing the potential epigenetic mechanisms involved in callus development can improve our understanding of the regeneration process of plant cells, which will be beneficial for overcoming regeneration recalcitrance in peach. In this study, we report on single-base resolution mapping of DNA methylation and reprogramming of the pattern of trimethylation of histone H3 at lysine 27 (H3K27me3) at the genome-wide level during the leaf-to-callus transition in peach.

Comprehensive analysis of quality characteristics in main commercial coffee varieties and wild Arabica in Kenya.

Coffee flavor is a complex commercial trait and its generation mechanisms remain largely unclear. Here, we investigated non-volatile and volatile compounds in the AA grade coffee beans of cultivated and wild accessions in Kenya. An increased accumulation of trigonelline and sucrose along with a decreased accumulation of caffeine and 5-caffeoylquinic acid or chlorogenic acid (CGA) relative to wild Arabica contribute to the improved flavor of commercial varieties.

PpHYH is responsible for light-induced anthocyanin accumulation in fruit peel of Prunus persica.

Peach Prunus persica is an economically important fruit tree crop worldwide. Although the external color of fruit is an important aspect of fruit quality, the mechanisms underlying its formation remain elusive in peach. Here, we report an elongated hypocotyl 5-homolog gene PpHYH involved in the regulation of anthocyanin pigmentation in peach fruit peel.

Two R2R3-MYB genes cooperatively control trichome development and cuticular wax biosynthesis in Prunus persica.

The fruit surface has an enormous impact on the external appearance and postharvest shelf-life of fruit. Here, we report two functionally redundant genes, PpMYB25 and PpMYB26, involved in regulation of fruit skin texture in peach. PpMYB25 can activate transcription of PpMYB26 and they both induce trichome development and cuticular wax accumulation, resulting in peach fruit with a fuzzy and dull appearance.

The MADS-box gene PpPI is a key regulator of the double-flower trait in peach.

Double flower is an invaluable trait in ornamental peach, but the mechanism underlying its development remains largely unknown. Here, we report the roles of ABCE model genes in double flower development in peach. A total of nine ABCE regulatory genes, including eight MADS-box genes and one AP2/EREBP gene, were identified in the peach genome.

Unraveling a genetic roadmap for improved taste in the domesticated apple.

Although taste is an important aspect of fruit quality, an understanding of its genetic control remains elusive in apple and other fruit crops. In this study, we conducted genomic sequence analysis of 497 Malus accessions and revealed erosion of genetic diversity caused by apple breeding and possible independent domestication events of dessert and cider apples. Signatures of selection for fruit acidity and size, but not for fruit sugar content, were detected during the processes of both domestication and improvement.

Potential Association of Reactive Oxygen Species With Male Sterility in Peach.

Male sterility is an important agronomic trait for hybrid vigor utilization and hybrid seed production, but its underlying mechanisms remain to be uncovered. Here, we investigated the mechanisms of male sterility in peach using a combined cytology, physiology, and molecular approach. Cytological features of male sterility include deformed microspores and tapetum cells along with absence of pollen grains.

Transcriptome analysis and molecular mechanism of linseed (Linum usitatissimum L.) drought tolerance under repeated drought using single-molecule long-read sequencing.

Background: Oil flax (linseed, Linum usitatissimum L.) is one of the most important oil crops., However, the increases in drought resulting from climate change have dramatically reduces linseed yield and quality, but very little is known about how linseed coordinates the expression of drought resistance gene in response to different level of drought stress (DS) on the genome-wide level.

Assessment of organic acid accumulation and its related genes in peach.

Fruit acidity is an important determinant of peach organoleptic quality, but its regulatory mechanism remains elusive. Measurement of organic acids in ripe fruits of seventy-five peach cultivars revealed the predominant components malate and citrate, accompanied by quinate. Organic acid accumulation increased at early stages of fruit growth, but exhibited a more dramatic reduction in low-acid cultivar during later stages of fruit development compared to high-acid cultivars.

The sucrose transporter MdSUT4.1 participates in the regulation of fruit sugar accumulation in apple.

Background: Sugar content is an important determinant of fruit sweetness, but details on the complex molecular mechanism underlying fruit sugar accumulation remain scarce. Here, we report the role of sucrose transporter (SUT) family in regulating fruit sugar accumulation in apple.

Results: Gene-tagged markers were developed to conduct candidate gene-based association study, and an SUT4 member MdSUT4.

Identification of EIL and ERF Genes Related to Fruit Ripening in Peach.

Peach () is a climacteric fruit with a relatively short shelf life due to its fast ripening or softening process. Here, we report the association of gene families encoding ethylene insensitive-3 like (EIL) and ethylene response factor (ERF) with fruit ripening in peach. In total, 3 and 12 PpERFs were highly expressed in fruit, with the majority showing a peak of expression at different stages.

Evolutionary rate variation among genes involved in galactomannan biosynthesis in .

The endosperm cell walls of mature coffee seeds accumulate large amounts of mannan storage polysaccharides, which serve as nutrient reserve for embryo and contribute to beverage quality. Our study investigated the evolutionary patterns of key galactomannan (GM) biosynthesis genes using / ratio, synteny, and phylogenetic analysis and detected heterogeneity in rate of evolution among gene copies. Selection ratio index revealed evidence of positive selection in the branch editing gene () at Cc11_g15950 copy ( = 1.

Development of a fast and efficient root transgenic system for functional genomics and genetic engineering in peach.

Peach is an economically import fruit crop worldwide, and serves as a model species of the Rosaceae family as well. However, peach functional genomics studies are severely hampered due to its recalcitrance to regeneration and stable transformation. Here, we report a fast and efficient Agrobacterium rhizogenes-mediated transformation system in peach.

Functional Analysis Reveals the Regulatory Role of Encoding Tonoplast Sugar Transporter in Sugar Accumulation of Peach Fruit.

Sugar content is related to fruit sweetness, and the complex mechanisms underlying fruit sugar accumulation still remain elusive. Here, we report a peach gene encoding tonoplast sugar transporter that is located in the quantitative trait loci (QTL) interval on Chr5 controlling fruit sucrose content. One derived Cleaved Amplified Polymorphic Sequence (dCAPS) marker was developed based on a nonsynonymous G/T variant in the third exon of .

Analysis of sorbitol content variation in wild and cultivated apples.

Background: Sorbitol is the major sugar alcohol in apple and its accumulation in fruit is associated with fruit sweetness. However, little is known about variation in sorbitol content in fruits of apple germplasm. In this study, we investigated sorbitol content in mature fruits of 243 apple cultivars and 20 wild relatives using high-performance liquid chromatography (HPLC).

Determination of Predominant Organic Acid Components in Species: Correlation with Apple Domestication.

Significant variation in organic acid components was detected in mature fruits of 101 apple accessions using high-performance liquid chromatography. The species predominantly accumulated malic acid and citric acid, whereas wild fruits exhibited significantly higher levels of organic acid content than that in cultivated fruits. Differential accumulation patterns during fruit developmental stages was detected between malic acid and citric acid, thus suggesting a complex genetic regulation mechanism of organic acid metabolism in apple fruit.

Activator-type R2R3-MYB genes induce a repressor-type R2R3-MYB gene to balance anthocyanin and proanthocyanidin accumulation.

Anthocyanin and proanthocyanidin (PA) accumulation is regulated by both myeloblastosis (MYB) activators and repressors, but little information is available on hierarchical interactions between the positive and negative regulators. Here, we report on a R2R3-MYB repressor in peach, designated PpMYB18, which acts as a negative regulator of anthocyanin and PA accumulation. PpMYB18 can be activated by both anthocyanin- and PA-related MYB activators, and is expressed both at fruit ripening and juvenile stages when anthocyanins or PAs, respectively, are being synthesized.

A Ma10 gene encoding P-type ATPase is involved in fruit organic acid accumulation in apple.

Acidity is one of the main determinants of fruit organoleptic quality. Here, comparative transcriptome analysis was conducted between two cultivars that showed a significant difference in fruit acidity, but contained homozygous non-functional alleles at the major gene Ma1 locus controlling apple fruit acidity. A candidate gene for fruit acidity, designated M10, was identified.

Two amino acid changes in the R3 repeat cause functional divergence of two clustered MYB10 genes in peach.

R2R3-MYB genes play a pivotal role in regulating anthocyanin accumulation. Here, we report two tandemly duplicated R2R3-MYB genes in peach, PpMYB10.1 and PpMYB10.

Investigation of benzylisoquinoline alkaloid biosynthetic pathway and its transcriptional regulation in lotus.

Lotus predominantly accumulates benzylisoquinoline alkaloids (BIAs), but their biosynthesis and regulation remain unclear. Here, we investigated structural and regulatory genes involved in BIA accumulation in lotus. Two clustered genes were identified to be responsible for the biosynthesis of bis-BIAs and aporphine-type BIAs, respectively, and their tissue-specific expression causes divergence in alkaloid component between leaf and embryo.

Evolutionary origin of the NCSI gene subfamily encoding norcoclaurine synthase is associated with the biosynthesis of benzylisoquinoline alkaloids in plants.

Sacred lotus is rich in biologically active compounds, particularly benzylisoquinoline alkaloids (BIAs). Here, we report on isolation of genes encoding (S)-norcoclaurine synthase (NCS) in sacred lotus, which is a key entry-enzyme in BIA biosynthesis. Seven NCS genes, designated NnNCS1 through NnNCS7, were identified in the sacred lotus genome, and five are located next to each other within a 83 kb region on scaffold 8.

Copy number variation of a gene cluster encoding endopolygalacturonase mediates flesh texture and stone adhesion in peach.

Texture is an important attribute affecting consumer perception of fruit quality. Peach melting flesh and flesh adhesion to stone (endocarp) are simply inherited and controlled by the F-M locus on linkage group (LG) 4. Here, we report that two genes encoding endopolygalacturonase (endoPG) in the F-M locus, designated PpendoPGF and PpendoPGM, are associated with the melting flesh and stone adhesion traits.

Analysis of Isoquinoline Alkaloid Composition and Wound-Induced Variation in Nelumbo Using HPLC-MS/MS.

Alkaloids are the most relevant bioactive components in lotus, a traditional herb in Asia, but little is known about their qualitative and quantitative distributions. Here, we report on the alkaloid composition in various lotus organs. Lotus laminae and embryos are rich in isoquinoline alkaloids, whereas petioles and rhizomes contain trace amounts of alkaloids.