Transcriptomics Identifies Differentially Expressed Genes Inducing Tuber Formation in Early- and Late-Maturing...

Area of Science:

• Plant genetics and molecular biology
• Agricultural science
• Crop development

Background:

• Potato tuberization timing is influenced by genetics, environment, and maturity.
• Understanding tuberization regulation is vital for potato production.
• Key molecular regulators of potato tuberization remain largely unidentified.

Purpose of the Study:

• To identify key genes controlling the transition to potato tuberization.
• To investigate the role of specific differentially expressed genes (DEGs) in tuber formation.
• To functionally verify the role of StYABBY1 in potato tuberization and leaf development.

Main Methods:

• Grafting experiments using early-maturing (Favorita) and late-maturing (Qingshu 9) potato varieties.
• Comprehensive transcriptome analysis of functional leaves and stolons in grafted plants.
• Gene expression analysis, including overexpression and RNA interference (RNAi) of StYABBY1.

Main Results:

• Grafting an early-maturing scion onto a late-maturing rootstock induced early tuber formation.
• 593 differentially expressed genes (DEGs), including 38 transcription factors, were identified.
• StYABBY1 was identified as a key DEG; its overexpression reduced leaf area and inhibited tuber formation, while RNAi had no effect on leaf area and promoted tuber formation.

Conclusions:

• StYABBY1 plays a significant role in regulating potato leaf size and inhibiting tuber formation.
• Identified DEGs, including PIF5, bHLH93, CBF3, ERF109, TCP19, and YABBY1, are proposed as key regulators of tuberization.
• This study provides novel insights into the genetic control of potato tuberization timing.