Toward unveiling transcriptome dynamics and regulatory modules at the maternal/filial interface of developing maize...

Area of Science:

• Plant Biology
• Molecular Genetics
• Transcriptomics

Background:

• The basal region of maize kernels is vital for nutrient transport from the mother plant to the developing seed.
• Transcriptome dynamics at this maternal/filial interface are not well understood.
• Understanding these dynamics is crucial for improving seed development and yield.

Purpose of the Study:

• To investigate the transcriptome dynamics of the maize kernel's basal maternal/filial interface.
• To identify key genes and regulatory networks involved in nutrient transfer during kernel development.
• To explore the function of specific transcription factors in regulating basal-specific transporters.

Main Methods:

• High-temporal-resolution RNA sequencing of basal and upper kernel regions (4-32 days after pollination).
• Gene Ontology (GO) term analysis and Weighted Gene Co-expression Network Analysis (WGCNA) on highly expressed genes in the basal region.
• Genome-wide DNA affinity purification sequencing and promoter transactivation assays to study transcription factor (TF) function.

Main Results:

• Identified five MADS-box transcription factors as key regulators (hubs) in the early-stage basal region.
• Discovered significant enrichment of GO terms related to transcriptional regulation and transporters in the filling-stage basal region.
• Demonstrated that three hub TFs regulate 10 basal-specific transporter genes involved in nutrient transfer (sugars, amino acids, ions).

Conclusions:

• Provides novel insights into the transcriptomic dynamics and regulatory modules of the maize kernel's maternal/filial interface.
• Highlights the potential roles of identified MADS-box TFs in maize kernel development, drawing parallels with studies in rice and Arabidopsis.
• Suggests that these TFs are critical regulators of nutrient transporters, essential for seed development and function.