Gibberellin in Regulating Poplar Growth, Development, and Stress Responses

Area of Science:

• Plant Biology
• Molecular Biology
• Forestry

Background:

• Gibberellic acid (GA) is crucial for plant growth, development, and stress responses.
• Poplars possess unique GA regulation due to their woody characteristics like continuous cambium activity and dormancy.
• GA pathways are conserved but exhibit tissue-specific gene expression in poplars.

Purpose of the Study:

• To review the synthesis, metabolism, and signaling pathways of GA in poplars.
• To elucidate GA's role in woody-specific traits and stress responses in poplars.
• To provide theoretical support for GA research in woody plants and forest tree breeding.

Main Methods:

• Literature review of GA synthesis, metabolism, and signaling in poplars.
• Analysis of GA's interaction with other hormones (IAA, ABA, JA) and regulatory elements (miRNAs, transcription factors).
• Examination of GA's role in abiotic and biotic stress responses in poplars.

Main Results:

• Poplar GA synthesis genes (e.g., KS1, KS2) show vascular tissue-specific expression.
• The GID1-DELLA pathway is central to GA signaling, modulating gene expression via ubiquitination.
• GA interacts with other hormones and regulatory factors to balance growth and defense under stress.

Conclusions:

• Poplars utilize distinct GA regulatory mechanisms for woody traits and stress adaptation.
• GA downregulation and DELLA accumulation enhance abiotic stress resistance.
• GA integrates with miRNAs and transcription factors, mediated by the DELLA-MYC2 module, for biotic stress management.