Crop Biotech Update

OsIPMS1 Gene Involved in Seed Vigor and Energy Metabolism in Rice

July 18, 2018

Seed vigor is an imperative trait for the direct seeding of rice. Isopropylmalate synthase (IPMS) is known to catalyze an important step in leucine (Leu) synthesis, but its effect on seed vigor remains unclear. Nanjing Agricultural University researchers led by Yongqi He investigated the role of rice OsIPMS1 and OsIPMS2 genes in seed vigor.

Both OsIPMS1 and OsIPMS2 catalyze Leu synthesis, and Leu feedback inhibits their activities. Disruption of OsIPMS1 via CRISPR-Cas9 resulted in low seed vigor under various conditions, which might be associated with the reduction of amino acids in germinating seeds. Eleven amino acids involved in stress tolerance, gibberellic acid synthesis and tricarboxylic acid cycle were significantly reduced in osipms1 mutants compared to wildtypes during seed germination.

A total of 1,209 differentially expressed genes (DEGs) were found in the osipms1a mutant, most of which were involved in glycolysis, protein processing, pyruvate, carbon, fructose and mannose metabolism. Further analysis confirmed that the role of OsIPMS1 in seed vigor is involved in starch hydrolysis, glycolytic activity and energy levels in germinating seeds.

This study provides insights into the function of OsIPMS1 on seed vigor and should have practical applications in the improvement of rice.

For more information, read the article in Plant Biotechnology Journal.