Integrative Analysis of Omics Reveals RdDM Pathway Participation in the Initiation of Rice Microspore Embryogenesis...

Area of Science:

• Plant Science
• Epigenetics
• Molecular Biology

Background:

• Abiotic stress impacts plant reproductive development.
• Mechanisms linking floral bud pre-treatment and microspore embryogenesis are not fully understood.

Purpose of the Study:

• Investigate dynamic epigenetic changes in rice microspores under cold stress.
• Clarify the role of DNA methylation and small RNAs in microspore embryogenesis initiation.

Main Methods:

• Bisulfite sequencing, sRNA-seq, and RNA-seq were employed.
• Analysis of DNA methylation dynamics (DMRs) and small RNA profiles.
• Identification of differentially expressed genes (DEGs) and their regulatory pathways.

Main Results:

• A 10-day cold treatment is essential for rice microspore embryogenesis initiation.
• Cold stress induced dynamic changes in DNA methylation and small RNA proportions.
• The RNA-directed DNA methylation (RdDM) pathway and auxin-related gene OsHOX28 are implicated in microspore embryogenesis.

Conclusions:

• Epigenetic reprogramming via DNA methylation and sRNAs is critical for cold-induced microspore embryogenesis.
• The RdDM pathway plays a significant role in initiating rice microspore embryogenesis.
• OsHOX28 upregulation, potentially RdDM-mediated, is crucial for this process.