Targeted Mutagenesis of P450 Gene Confers Male Sterility in Monocots

Targeted mutagenesis using programmable DNA endonucleases, such as CRISPR and TALENs, is promising in studying gene function in plants and in improving crop yields. Recently, a method that eliminates the need to emasculate the female inbred during hybrid seed production has been described. The system relies on identifying genes critical to anther and pollen development, such as the P450 fertility gene in maize, known as Ms26. However, theP450 gene has not been isolated in other monocots.

The team led by A. Mark Cigan from DuPont Pioneer designed and used a homing endonuclease, Ems26+, to generate in planta mutations in rice, sorghum and wheat orthologs of maize Ms26. Just like in maize, mutations in Ms26 ortholog genes in rice and sorghum prevent pollen formation, resulting in male sterile plants. However, allohexaploid wheat plants that have similar P450 gene mutations in only one of its three genomes were still male fertile.

Targeted mutagenesis and subsequent characterization of male fertility genes in sorghum and wheat could be an important step in improving yields through hybrid seed technology.

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