Changes in Endopolygalacturonase Levels and Characterization of a Putative Endo-PG Gene during Fruit Softening in Peach Genotypes with Nonmelting and Melting Flesh Fruit Phenotypes

• Published in: The New phytologist Vol. 171; no. 2; pp. 315 - 328
• Main Authors: Morgutti, S., Negrini, N., Nocito, F. F., Ghiani, A., Bassi, D., Cocucci, M.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science 01.07.2006; Blackwell Publishing Ltd; Blackwell
• Subjects: Agronomy. Soil science and plant productions; Alkanesulfonic Acids; Amino Acid Sequence; Base Sequence; Biological and medical sciences; Blotting, Western - methods; Bolero dance; Cell walls; cleaved amplified polymorphic sequence (CAPS); Complementary DNA; Cyclohexylamines; DNA; Economic plant physiology; endopolygalacturonase (endo‐PG) levels; endo‐PG expression; Fructification and ripening; Fructification, ripening. Postharvest physiology; Fruit - enzymology; Fruit - growth & development; Fruits; Fundamental and applied biological sciences. Psychology; Gels; Gene Expression; Genes, Plant; Genomics; Genotype; Growth and development; marker‐assisted selection (MAS); Mesocarp; Molecular Sequence Data; nonmelting flesh/melting flesh phenotype; Phenotypes; Plant physiology and development; Polygalacturonase - genetics; Polygalacturonase - metabolism; Polymorphism, Genetic; Prunus; Prunus - enzymology; Prunus - genetics; Prunus - growth & development; Prunus persica; Ripening; Sequence Alignment; Sequence Analysis, DNA; single nucleotide polymorphisms (SNPs); Vegetative and sexual reproduction, floral biology, fructification; endopolygalacturonase (endo-PG) levels; Transcription; Rosaceae; marker-assisted selection (MAS); Gene; Dicotyledones; Angiospermae; Sequencing; Biochemical analysis; Fruit; Enzyme; endo-PG expression; Mesocarp; cleaved amplified polymorphic sequence (CAPS); Polygalacturonase; Prunus persica; Protein; Phenotype; Glycosidases; single nucleotide polymorphisms (SNPs); nonmelting flesh/melting flesh phenotype; Hydrolases; Spermatophyta; Single nucleotide polymorphism; O-Glycosidases
• ISSN: 0028-646X; 1469-8137
• DOI: 10.1111/j.1469-8137.2006.01763.x

• The changes in endopolygalactu ronase (endo-PG) levels and endo-PG expression in nonmelting flesh (NMF) and melting flesh (MF) peach fruits (Prunus persica) during softening were studied. The endo-PG gene was analysed to identify polymorphisms exploitable for early marker-assisted selection (MAS) of flesh texture. • The role of endo-PG in softening was assessed by western and northern blotting and by biochemical analyses. Polymorphisms in the endo-PG gene were revealed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. • An endo-PG protein was detected in both NMF and MF fruits. The levels of this endo-PG protein were higher and increased with softening in MF fruits, but remained lower and were constant in NMF fruits. The different levels of endo-PG appeared to be caused by the differential expression of an endo-PG gene, whose open-reading frame (ORF) showed five single nucleotide polymorphisms (SNPs) in NMF 'Oro A' compared with MF 'Bolero'. One of these SNPs allowed us to determine the allelic configuration at the melting flesh (M) locus and also seemed to be exploitable for early MAS in other NMF/MF phenotypes. • The NMF phenotype does not seem to be caused by a large deletion of the endo-PG gene.