Determining the function of ripening associated genes and biochemical changes during tomato (Solanum lycopersicum L.) fruit maturation

This article examines biochemical altera-
tions and gene expression changes during tomato fruit
physiology. The chroma index increases from mature
green (41.27) to red ripe (48.36) stages, and the tex-
ture softens from mature green (43.56 N) to red ripe
(24.75 N). Reducing sugar and total carotenoid lev-
els rise at the red ripe stage. Free radical content
was elevated in the early stages (7 nM) of ripening
and declined at the later stages (4 nM). The specific
activity of α-mannosidase and β-N-acetyl hexosa-
minidase was high at the breaker (0.077 & 0.075 U/
mg, respectively) stages, while polygalacturonase
activity was high at red ripe (1.173 U/mg) stage.
qPCR experiments revealed that the α-mannosidase
was upregulated during the breaker (1.2 fold) stages
of tomato ripening, the β-N-acetyl Hexosaminidase
was upregulated throughout the breaker (2 fold), and
pink (1.2 fold) stages of tomato ripening, and the
β-xylosidase was upregulated significantly during the breaker stage (3.9 fold) of tomato ripening. The cur-
rent findings revealed that the α-Mannosidase (0.77),
β-N-acetylhexosaminidase (0.99), xylosidase (0.85),
ethylene-responsive factors (0.86), aminocylco pro-
pane carboxylic oxidase (0.90), and pectin methy-
lesterase (0.83), were significantly associated with
textural softening. Polygalacturonase (0.75) posi-
tively correlated to reducing sugar formation, amino-
cylco propane carboxylic synthase 4 (0.96) expres-
sion correlates with chroma changes during tomato
fruit ripening. These correlations illustrate the com-
plex interplay between gene expression and the physi-
cal and biochemical changes occurring during tomato
fruit ripening.