Natural variation in GmSW17 controls seed size in soybean

Area of Science:

• Plant genetics and breeding
• Molecular biology
• Crop science

Background:

• Seed size/weight is crucial for crop yield in soybeans.
• Limited genes controlling soybean seed size have been identified.
• Understanding genetic factors is vital for improving soybean yield.

Purpose of the Study:

• To identify major genes controlling soybean seed width and weight.
• To elucidate the molecular mechanism underlying seed size regulation.
• To explore the potential of identified genes in soybean breeding.

Main Methods:

• Genome-wide association study (GWAS) to identify quantitative trait loci (QTL).
• Gene cloning and characterization of GmSW17.
• Functional analysis involving protein interactions and gene expression studies.
• Population genetics analysis to assess selection history.

Main Results:

• A major QTL, GmSW17 (Seed Width 17), was identified on chromosome 17.
• GmSW17 encodes a ubiquitin-specific protease involved in a deubiquitinase module.
• This module regulates histone ubiquitination (H2Bub) and inhibits cell cycle progression (G1-to-S transition).
• GmSW17 was under artificial selection during domestication but not fixed in modern cultivars.

Conclusions:

• GmSW17 is a predominant gene influencing soybean seed width/weight.
• The identified deubiquitinase module provides a novel mechanism for seed size regulation.
• GmSW17 presents a valuable target for enhancing soybean yield through breeding programs.