Multi-omic characterization of the maize GPI synthesis mutant gwt1 with defects in kernel development

Area of Science:

• Plant Biology
• Molecular Genetics
• Biochemistry

Background:

• Glycosylphosphatidylinositol (GPI) and GPI-anchored proteins (GAPs) are vital for plant development, particularly in Arabidopsis.
• Their roles in monocot kernel endosperm development remain largely unexplored.

Purpose of the Study:

• To investigate the function of GPI-related genes in maize kernel development using a multi-omic approach.
• To identify novel GAPs involved in maize kernel development.

Main Methods:

• Identified 48 maize orthologs of human GPI synthesis and lipid remodeling genes.
• Utilized plasma membrane proteomics to analyze protein abundance in wild-type and gwt1 mutant kernels.
• Performed comparative proteomic analysis of 10-day-old developing kernels.

Main Results:

• Null mutation in ZmGWT1 resulted in a maize kernel mutant (gwt1) with defects in the basal endosperm transport layer (BETL).
• Proteomic analysis identified 4,981 proteins, including 1,638 membrane-anchored proteins.
• Forty-seven of 256 predicted GAPs showed differential accumulation; two BETL-specific GAPs were significantly decreased in the gwt1 mutant membrane proteome.

Conclusions:

• GPI and GAPs play significant roles in maize endosperm development.
• ZmGWT1 and identified GAPs are potential candidates for further research into kernel development regulatory networks.