Transcriptome analysis during ripening of table grape berry cv. Thompson Seedless

Area of Science:

• Plant Biology
• Molecular Biology
• Fruit Development

Background:

• Fruit ripening significantly impacts organoleptic qualities.
• Climacteric fruit ripening is well-understood, unlike non-climacteric fruit such as grapes.
• Limited knowledge exists on gene expression during non-climacteric fruit ripening.

Purpose of the Study:

• To investigate gene expression changes during table grape berry ripening.
• To characterize the molecular processes underlying ripening in non-climacteric fruit.

Main Methods:

• Utilized Illumina-based RNA-Seq transcriptome analysis.
• Examined four developmental stages of 'Thompson Seedless' table grapes from veraison to harvest.

Main Results:

• Observed increased transcription of genes involved in chlorophyll and lipid degradation, macromolecule recycling, and nucleosome organization.
• Noted decreased transcription of genes related to chloroplast integrity and amino acid synthesis.
• Identified leaf senescence-associated processes near harvest.
• Detected high transcriptional activity in gene regulation, cytoskeletal organization, and cell wall metabolism before harvest.
• Found increased transcription of glycolysis and respiration genes, unusual for non-climacteric fruit ripening.

Conclusions:

• Grape ripening involves distinct transcriptional shifts, including senescence-like processes and cell wall modifications.
• Unexpectedly high metabolic activity, particularly in glycolysis and respiration, characterizes grape ripening.
• These findings provide insights into the molecular mechanisms of non-climacteric fruit development.