Insights into the Transcriptional Reprogramming in Tomato Response to PSTVd Variants Using Network Approaches

Area of Science:

• Plant pathology
• Molecular biology
• Genomics

Background:

• Viroids are non-coding RNA pathogens causing significant crop diseases.
• Viroid-induced symptoms involve developmental alterations driven by genetic regulation.
• Understanding host responses to viroids is crucial for crop protection.

Purpose of the Study:

• To identify master transcription regulators (MTRs) and their targets in tomato plants infected with Potato Spindle Tuber Viroid (PSTVd).
• To elucidate the global mechanisms of host-pathogen interaction and symptom development.
• To analyze differential gene expression in response to mild and severe PSTVd variants.

Main Methods:

• Integration of transcriptomic data from tomato roots and leaves.
• Application of gene regulatory network (GRN) analysis.
• Identification and functional enrichment of affected biological processes and transcription factors.

Main Results:

• Specific bHLH, MYB, and ERF transcription factors were identified as key regulators.
• bHLH-MTRs are associated with metabolism and plant defense; MYB-MTRs with signaling and hormone processes.
• ERF-MTRs correlate with severe symptoms, while ZNF, tf3a, BZIP, and NAC TFs act as unique MTRs.

Conclusions:

• The study provides a foundation for understanding PSTVd-host genome interactions.
• Identified MTRs offer potential targets for managing viroid-induced symptom development in tomato.
• A bHLH-TF family member may play a role in post-translational regulation of hormone signaling.