Transcriptome-wide analysis of epitranscriptome and translational efficiency associated with heterosis in maize.

Area of Science:

• Plant genetics and molecular biology
• Epigenetics and gene regulation
• Agricultural science

Background:

• Heterosis, or hybrid vigor, enhances crop productivity but its molecular basis is poorly understood.
• Understanding gene regulation in hybrids is crucial for improving crop yields.

Purpose of the Study:

• To investigate the roles of mRNA abundance, m6A methylation, and translational efficiency in maize heterosis.
• To determine how these regulatory layers contribute to hybrid vigor at the seedling stage.

Main Methods:

• Generated transcriptome-wide profiles of mRNA abundance, m6A methylation, and translational efficiency.
• Compared data from maize F1 hybrid (B73×Mo17) and its parental lines.
• Analyzed gene expression patterns and regulatory layer contributions.

Main Results:

• Global m6A levels were unchanged, but more genes gained m6A modifications in the hybrid.
• m6A modification and translational efficiency showed greater variation than mRNA abundance.
• Most m6A-modified genes in the hybrid exhibited non-additive expression patterns, exceeding those at mRNA abundance and translational efficiency levels.
• Non-additive genes were coordinated by combinations of the three regulatory layers.

Conclusions:

• Transcriptional and post-transcriptional regulation distinctly contribute to heterosis in hybrid maize.
• Integrated multi-omics analysis provides a framework for understanding gene regulation in hybrids.
• Findings pave the way for exploring molecular mechanisms of hybrid vigor.