Maize Urb2 protein is required for kernel development and vegetative growth by affecting pre-ribosomal RNA processing

Area of Science:

• Plant Molecular Biology
• Cellular Biology
• Genetics

Background:

• Ribosome biogenesis is essential for eukaryotic cell function.
• Urb2 protein's role in ribosome biogenesis is known in yeast, but its function in plants is uncharacterized.
• The Urb2 domain shows limited conservation between yeast and plants.

Purpose of the Study:

• To investigate the function of Urb2 protein in maize.
• To understand the role of ZmUrb2 in ribosome biogenesis and plant development.
• To identify the impact of ZmUrb2 on maize kernel traits.

Main Methods:

• Isolation and characterization of a maize urb2 mutant.
• Positional cloning and transgenic analysis to identify the gene.
• Biochemical assays to analyze ribosome subunit ratios and pre-rRNA processing.
• Transcriptome profiling to assess gene expression changes.
• Association analysis of ZmUrb2 natural variations with kernel length.

Main Results:

• The maize urb2 mutant exhibits defects in kernel and vegetative growth.
• ZmUrb2 encodes an Urb2 domain-containing protein essential for ribosome biogenesis.
• The mutant displays altered ratios of ribosomal subunits and accumulation of pre-rRNA intermediates.
• ZmUrb2 influences the expression of ribosome-related genes.
• Natural variations in ZmUrb2 are linked to maize kernel length.

Conclusions:

• Maize Urb2 protein plays a vital role in ribosome biogenesis by affecting pre-rRNA processing.
• ZmUrb2 is essential for normal maize development, including kernel growth.
• Understanding ZmUrb2 function provides insights into plant growth regulation and ribosome assembly.