The PbWRKY7-PbMADS2 transcriptional module coordinates volatile ester biosynthesis in pear fruit

Area of Science:

• Plant Biochemistry
• Molecular Biology
• Agricultural Science

Background:

• Fruit aroma is crucial for quality and consumer preference.
• Understanding volatile compound biosynthesis regulation is key to improving fruit aroma.
• Pear varieties with intense aromas offer valuable insights into aroma compound regulation.

Purpose of the Study:

• To elucidate the molecular mechanisms governing ester biosynthesis in pears.
• To identify key enzymes and regulatory factors involved in pear aroma development.
• To uncover regulatory targets for enhancing fruit aroma quality.

Main Methods:

• Gas chromatography-mass spectrometry (GC-MS) and RNA sequencing (RNA-Seq) for metabolite and gene analysis.
• Biochemical assays including dual-luciferase, yeast one-hybrid (Y1H), and electrophoretic mobility shift assays (EMSA) to identify transcriptional regulation.
• Protein-protein interaction studies like yeast two-hybrid (Y2H), luciferase complementation assay (LCA), and GST pull-down assays to analyze protein complex formation.

Main Results:

• PbAAT1 was identified as the key enzyme in pear ester biosynthesis.
• PbWRKY7 was confirmed as an upstream transcriptional activator of PbAAT1.
• The interaction between PbWRKY7 and PbMADS2 synergistically enhanced PbAAT1 expression, indicating a regulatory network.

Conclusions:

• A novel molecular network involving PbWRKY7 and PbMADS2 in regulating PbAAT1 expression was discovered.
• This network plays a crucial role in controlling ester biosynthesis in pears.
• The findings provide potential targets for genetic engineering to enhance pear aroma quality.